Fix critical bugs and issues found in alternator code review

Co-authored-by: nyh <584227+nyh@users.noreply.github.com>

.github/workflows/backport-pr-fixes-validation.yaml

@@ -18,7 +18,7 @@ jobs:
             
             // Regular expression pattern to check for "Fixes" prefix
             // Adjusted to dynamically insert the repository full name
-            const pattern = `Fixes:? ((?:#|${repo.replace('/', '\\/')}#|https://github\\.com/${repo.replace('/', '\\/')}/issues/)(\\d+)|([A-Z]+-\\d+))`;
+            const pattern = `Fixes:? ((?:#|${repo.replace('/', '\\/')}#|https://github\\.com/${repo.replace('/', '\\/')}/issues/)(\\d+)|(?:https://scylladb\\.atlassian\\.net/browse/)?([A-Z]+-\\d+))`;
             const regex = new RegExp(pattern);
             
             if (!regex.test(body)) {

.github/workflows/iwyu.yaml

@@ -14,7 +14,8 @@ env:
   CLEANER_DIRS: test/unit exceptions alternator api auth cdc compaction db dht gms index lang message mutation mutation_writer node_ops raft redis replica service
   SEASTAR_BAD_INCLUDE_OUTPUT_PATH: build/seastar-bad-include.log
 
-permissions: {}
+permissions:
+  contents: read
 
 # cancel the in-progress run upon a repush
 concurrency:
@@ -34,8 +35,6 @@ jobs:
       - uses: actions/checkout@v4
         with:
           submodules: true
-      - run: |
-          sudo dnf -y install clang-tools-extra
       - name: Generate compilation database
         run: |
           cmake                                         \

SCYLLA-VERSION-GEN

@@ -78,7 +78,7 @@ fi
 
 # Default scylla product/version tags
 PRODUCT=scylla
-VERSION=2026.1.0-dev
+VERSION=2026.2.0-dev
 
 if test -f version
 then

alternator/conditions.cc

@@ -244,7 +244,10 @@ static bool is_set_of(const rjson::value& type1, const rjson::value& type2) {
 
 // Check if two JSON-encoded values match with the CONTAINS relation
 bool check_CONTAINS(const rjson::value* v1, const rjson::value& v2, bool v1_from_query, bool v2_from_query) {
-    if (!v1) {
+    if (!v1 || !v1->IsObject() || v1->MemberCount() == 0) {
+        return false;
+    }
+    if (!v2.IsObject() || v2.MemberCount() == 0) {
         return false;
     }
     const auto& kv1 = *v1->MemberBegin();

alternator/consumed_capacity.cc

@@ -45,7 +45,7 @@ bool consumed_capacity_counter::should_add_capacity(const rjson::value& request)
 }
 
 void consumed_capacity_counter::add_consumed_capacity_to_response_if_needed(rjson::value& response) const noexcept {
-    if (_should_add_to_reponse) {
+    if (_should_add_to_response) {
         auto consumption = rjson::empty_object();
         rjson::add(consumption, "CapacityUnits", get_consumed_capacity_units());
         rjson::add(response, "ConsumedCapacity", std::move(consumption));
@@ -53,7 +53,9 @@ void consumed_capacity_counter::add_consumed_capacity_to_response_if_needed(rjso
 }
 
 static uint64_t calculate_half_units(uint64_t unit_block_size, uint64_t total_bytes, bool is_quorum) {
-    uint64_t half_units = (total_bytes + unit_block_size -1) / unit_block_size; //divide by unit_block_size and round up
+    // Avoid potential integer overflow when total_bytes is close to UINT64_MAX
+    // by using division with modulo instead of addition before division
+    uint64_t half_units = total_bytes / unit_block_size + (total_bytes % unit_block_size != 0 ? 1 : 0);
 
     if (is_quorum) {
         half_units *= 2;

alternator/consumed_capacity.hh

@@ -28,9 +28,9 @@ namespace alternator {
 class consumed_capacity_counter {
 public:
     consumed_capacity_counter() = default;
-    consumed_capacity_counter(bool should_add_to_reponse) : _should_add_to_reponse(should_add_to_reponse){}
+    consumed_capacity_counter(bool should_add_to_response) : _should_add_to_response(should_add_to_response){}
     bool operator()() const noexcept {
-        return _should_add_to_reponse;
+        return _should_add_to_response;
     }
 
     consumed_capacity_counter& operator +=(uint64_t bytes);
@@ -44,7 +44,7 @@ public:
     uint64_t _total_bytes = 0;
     static bool should_add_capacity(const rjson::value& request);
 protected:
-    bool _should_add_to_reponse = false;
+    bool _should_add_to_response = false;
 };
 
 class rcu_consumed_capacity_counter : public consumed_capacity_counter {

alternator/executor.cc

@@ -17,6 +17,7 @@
 #include "auth/service.hh"
 #include "db/config.hh"
 #include "db/view/view_build_status.hh"
+#include "locator/tablets.hh"
 #include "mutation/tombstone.hh"
 #include "locator/abstract_replication_strategy.hh"
 #include "utils/log.hh"
@@ -833,11 +834,13 @@ future<> executor::fill_table_size(rjson::value &table_description, schema_ptr s
             total_size = co_await _ss.estimate_total_sstable_volume(schema->id(), service::storage_service::ignore_errors::yes);
             const auto expiry = std::chrono::seconds{ _proxy.data_dictionary().get_config().alternator_describe_table_info_cache_validity_in_seconds() };
             // Note: we don't care when the notification of other shards will finish, as long as it will be done
-            // it's possible to get into race condition (next DescribeTable comes to other shard, that new shard doesn't have
-            // the size yet, so it will calculate it again) - this is not a problem, because it will call cache_newly_calculated_size_on_all_shards
-            // with expiry, which is extremely unlikely to be exactly the same as the previous one, all shards will keep the size coming with expiry that is further into the future.
-            // In case of the same expiry, some shards will have different size, which means DescribeTable will return different values depending on the shard
-            // which is also fine, as the specification doesn't give precision guarantees of any kind.
+            // A race condition is possible: if a DescribeTable request arrives on a different shard before
+            // that shard receives the cached size, it will recalculate independently. This is acceptable because:
+            // 1. Both calculations will cache their results with an expiry time
+            // 2. Expiry times are unlikely to be identical, so eventually all shards converge to the most recent value
+            // 3. Even if expiry times match, different shards may briefly return different table sizes
+            // 4. This temporary inconsistency is acceptable per DynamoDB specification, which doesn't guarantee
+            //    exact precision for DescribeTable size information
             co_await cache_newly_calculated_size_on_all_shards(schema, total_size, expiry);
         }
     }
@@ -1875,23 +1878,34 @@ future<executor::request_return_type> executor::create_table_on_shard0(service::
         auto ts = group0_guard.write_timestamp();
         utils::chunked_vector<mutation> schema_mutations;
         auto ksm = create_keyspace_metadata(keyspace_name, _proxy, _gossiper, ts, tags_map, _proxy.features(), tablets_mode);
+        locator::replication_strategy_params params(ksm->strategy_options(), ksm->initial_tablets(), ksm->consistency_option());
+        const auto& topo = _proxy.local_db().get_token_metadata().get_topology();
+        auto rs = locator::abstract_replication_strategy::create_replication_strategy(ksm->strategy_name(), params, topo);
         // Alternator Streams doesn't yet work when the table uses tablets (#23838)
         if (stream_specification && stream_specification->IsObject()) {
             auto stream_enabled = rjson::find(*stream_specification, "StreamEnabled");
             if (stream_enabled && stream_enabled->IsBool() && stream_enabled->GetBool()) {
-                locator::replication_strategy_params params(ksm->strategy_options(), ksm->initial_tablets(), ksm->consistency_option());
-                const auto& topo = _proxy.local_db().get_token_metadata().get_topology();
-                auto rs = locator::abstract_replication_strategy::create_replication_strategy(ksm->strategy_name(), params, topo);
                 if (rs->uses_tablets()) {
                     co_return api_error::validation("Streams not yet supported on a table using tablets (issue #23838). "
                     "If you want to use streams, create a table with vnodes by setting the tag 'system:initial_tablets' set to 'none'.");
                 }
             }
         }
-        // Creating an index in tablets mode requires the rf_rack_valid_keyspaces option to be enabled.
-        // GSI and LSI indexes are based on materialized views which require this option to avoid consistency issues.
-        if (!view_builders.empty() && ksm->uses_tablets() && !_proxy.data_dictionary().get_config().rf_rack_valid_keyspaces()) {
-            co_return api_error::validation("GlobalSecondaryIndexes and LocalSecondaryIndexes with tablets require the rf_rack_valid_keyspaces option to be enabled.");
+        // Creating an index in tablets mode requires the keyspace to be RF-rack-valid.
+        // GSI and LSI indexes are based on materialized views which require RF-rack-validity to avoid consistency issues.
+        if (!view_builders.empty() || _proxy.data_dictionary().get_config().rf_rack_valid_keyspaces()) {
+            try {
+                locator::assert_rf_rack_valid_keyspace(keyspace_name, _proxy.local_db().get_token_metadata_ptr(), *rs);
+            } catch (const std::invalid_argument& ex) {
+                if (!view_builders.empty()) {
+                    co_return api_error::validation(fmt::format("GlobalSecondaryIndexes and LocalSecondaryIndexes on a table "
+                        "using tablets require the number of racks in the cluster to be either 1 or 3"));
+                } else {
+                    co_return api_error::validation(fmt::format("Cannot create table '{}' with tablets: the configuration "
+                        "option 'rf_rack_valid_keyspaces' is enabled, which enforces that tables using tablets can only be created in clusters "
+                        "that have either 1 or 3 racks", table_name));
+                }
+            }
         }
         try {
             schema_mutations = service::prepare_new_keyspace_announcement(_proxy.local_db(), ksm, ts);
@@ -2114,9 +2128,12 @@ future<executor::request_return_type> executor::update_table(client_state& clien
                             co_return api_error::validation(fmt::format(
                                 "LSI {} already exists in table {}, can't use same name for GSI", index_name, table_name));
                         }
-                        if (p.local().local_db().find_keyspace(keyspace_name).get_replication_strategy().uses_tablets() &&
-                                !p.local().data_dictionary().get_config().rf_rack_valid_keyspaces()) {
-                            co_return api_error::validation("GlobalSecondaryIndexes with tablets require the rf_rack_valid_keyspaces option to be enabled.");
+                        try {
+                            locator::assert_rf_rack_valid_keyspace(keyspace_name, p.local().local_db().get_token_metadata_ptr(),
+                                    p.local().local_db().find_keyspace(keyspace_name).get_replication_strategy());
+                        } catch (const std::invalid_argument& ex) {
+                            co_return api_error::validation(fmt::format("GlobalSecondaryIndexes on a table "
+                                "using tablets require the number of racks in the cluster to be either 1 or 3"));
                         }
 
                         elogger.trace("Adding GSI {}", index_name);

alternator/streams.cc

@@ -491,7 +491,7 @@ future<executor::request_return_type> executor::describe_stream(client_state& cl
 
     if (!opts.enabled()) {
         rjson::add(ret, "StreamDescription", std::move(stream_desc));
-        return make_ready_future<executor::request_return_type>(rjson::print(std::move(ret)));
+        co_return rjson::print(std::move(ret));
     }
 
     // TODO: label
@@ -502,123 +502,121 @@ future<executor::request_return_type> executor::describe_stream(client_state& cl
     // filter out cdc generations older than the table or now() - cdc::ttl (typically dynamodb_streams_max_window - 24h)
     auto low_ts = std::max(as_timepoint(schema->id()), db_clock::now() - ttl);
 
-    return _sdks.cdc_get_versioned_streams(low_ts, { normal_token_owners }).then([db, shard_start, limit, ret = std::move(ret), stream_desc = std::move(stream_desc)] (std::map<db_clock::time_point, cdc::streams_version> topologies) mutable {
+    std::map<db_clock::time_point, cdc::streams_version> topologies = co_await _sdks.cdc_get_versioned_streams(low_ts, { normal_token_owners });
+    auto e = topologies.end();
+    auto prev = e;
+    auto shards = rjson::empty_array();
 
-        auto e = topologies.end();
-        auto prev = e;
-        auto shards = rjson::empty_array();
+    std::optional<shard_id> last;
 
-        std::optional<shard_id> last;
+    auto i = topologies.begin();
+    // if we're a paged query, skip to the generation where we left of.
+    if (shard_start) {
+        i = topologies.find(shard_start->time);
+    }
 
-        auto i = topologies.begin();
-        // if we're a paged query, skip to the generation where we left of.
-        if (shard_start) {
-            i = topologies.find(shard_start->time);
-        }
+    // for parent-child stuff we need id:s to be sorted by token
+    // (see explanation above) since we want to find closest
+    // token boundary when determining parent.
+    // #7346 - we processed and searched children/parents in
+    // stored order, which is not necessarily token order,
+    // so the finding of "closest" token boundary (using upper bound)
+    // could give somewhat weird results.
+    static auto token_cmp = [](const cdc::stream_id& id1, const cdc::stream_id& id2) {
+        return id1.token() < id2.token();
+    };
 
-        // for parent-child stuff we need id:s to be sorted by token
-        // (see explanation above) since we want to find closest
-        // token boundary when determining parent.
-        // #7346 - we processed and searched children/parents in
-        // stored order, which is not necessarily token order,
-        // so the finding of "closest" token boundary (using upper bound)
-        // could give somewhat weird results.
-        static auto token_cmp = [](const cdc::stream_id& id1, const cdc::stream_id& id2) {
-            return id1.token() < id2.token();
-        };
+    // #7409 - shards must be returned in lexicographical order,
+    // normal bytes compare is string_traits<int8_t>::compare.
+    // thus bytes 0x8000 is less than 0x0000. By doing unsigned
+    // compare instead we inadvertently will sort in string lexical.
+    static auto id_cmp = [](const cdc::stream_id& id1, const cdc::stream_id& id2) {
+        return compare_unsigned(id1.to_bytes(), id2.to_bytes()) < 0;
+    };
+
+    // need a prev even if we are skipping stuff
+    if (i != topologies.begin()) {
+        prev = std::prev(i);
+    }
+
+    for (; limit > 0 && i != e; prev = i, ++i) {
+        auto& [ts, sv] = *i;
+
+        last = std::nullopt;
+
+        auto lo = sv.streams.begin();
+        auto end = sv.streams.end();
 
         // #7409 - shards must be returned in lexicographical order,
-        // normal bytes compare is string_traits<int8_t>::compare.
-        // thus bytes 0x8000 is less than 0x0000. By doing unsigned
-        // compare instead we inadvertently will sort in string lexical.
-        static auto id_cmp = [](const cdc::stream_id& id1, const cdc::stream_id& id2) {
-            return compare_unsigned(id1.to_bytes(), id2.to_bytes()) < 0;
-        };
+        std::sort(lo, end, id_cmp);
 
-        // need a prev even if we are skipping stuff
-        if (i != topologies.begin()) {
-            prev = std::prev(i);
+        if (shard_start) {
+            // find next shard position
+            lo = std::upper_bound(lo, end, shard_start->id, id_cmp);
+            shard_start = std::nullopt;
         }
 
-        for (; limit > 0 && i != e; prev = i, ++i) {
-            auto& [ts, sv] = *i;
+        if (lo != end && prev != e) {
+            // We want older stuff sorted in token order so we can find matching
+            // token range when determining parent shard.
+            std::stable_sort(prev->second.streams.begin(), prev->second.streams.end(), token_cmp);
+        }
+
+        auto expired = [&]() -> std::optional<db_clock::time_point> {
+            auto j = std::next(i);
+            if (j == e) {
+                return std::nullopt;
+            }
+            // add this so we sort of match potential 
+            // sequence numbers in get_records result.
+            return j->first + confidence_interval(db);
+        }();
+
+        while (lo != end) {
+            auto& id = *lo++;
+
+            auto shard = rjson::empty_object();
+
+            if (prev != e) {
+                auto& pids = prev->second.streams;
+                auto pid = std::upper_bound(pids.begin(), pids.end(), id.token(), [](const dht::token& t, const cdc::stream_id& id) {
+                    return t < id.token();
+                });
+                if (pid != pids.begin()) {
+                    pid = std::prev(pid);
+                }
+                if (pid != pids.end()) {
+                    rjson::add(shard, "ParentShardId", shard_id(prev->first, *pid));
+                }
+            }
+
+            last.emplace(ts, id);
+            rjson::add(shard, "ShardId", *last);
+            auto range = rjson::empty_object();
+            rjson::add(range, "StartingSequenceNumber", sequence_number(utils::UUID_gen::min_time_UUID(ts.time_since_epoch())));
+            if (expired) {
+                rjson::add(range, "EndingSequenceNumber", sequence_number(utils::UUID_gen::min_time_UUID(expired->time_since_epoch())));
+            }
+
+            rjson::add(shard, "SequenceNumberRange", std::move(range));
+            rjson::push_back(shards, std::move(shard));
+            
+            if (--limit == 0) {
+                break;
+            }
 
             last = std::nullopt;
-
-            auto lo = sv.streams.begin();
-            auto end = sv.streams.end();
-
-            // #7409 - shards must be returned in lexicographical order,
-            std::sort(lo, end, id_cmp);
-
-            if (shard_start) {
-                // find next shard position
-                lo = std::upper_bound(lo, end, shard_start->id, id_cmp);
-                shard_start = std::nullopt;
-            }
-
-            if (lo != end && prev != e) {
-                // We want older stuff sorted in token order so we can find matching
-                // token range when determining parent shard.
-                std::stable_sort(prev->second.streams.begin(), prev->second.streams.end(), token_cmp);
-            }
-
-            auto expired = [&]() -> std::optional<db_clock::time_point> {
-                auto j = std::next(i);
-                if (j == e) {
-                    return std::nullopt;
-                }
-                // add this so we sort of match potential 
-                // sequence numbers in get_records result.
-                return j->first + confidence_interval(db);
-            }();
-
-            while (lo != end) {
-                auto& id = *lo++;
-
-                auto shard = rjson::empty_object();
-
-                if (prev != e) {
-                    auto& pids = prev->second.streams;
-                    auto pid = std::upper_bound(pids.begin(), pids.end(), id.token(), [](const dht::token& t, const cdc::stream_id& id) {
-                        return t < id.token();
-                    });
-                    if (pid != pids.begin()) {
-                        pid = std::prev(pid);
-                    }
-                    if (pid != pids.end()) {
-                        rjson::add(shard, "ParentShardId", shard_id(prev->first, *pid));
-                    }
-                }
-
-                last.emplace(ts, id);
-                rjson::add(shard, "ShardId", *last);
-                auto range = rjson::empty_object();
-                rjson::add(range, "StartingSequenceNumber", sequence_number(utils::UUID_gen::min_time_UUID(ts.time_since_epoch())));
-                if (expired) {
-                    rjson::add(range, "EndingSequenceNumber", sequence_number(utils::UUID_gen::min_time_UUID(expired->time_since_epoch())));
-                }
-
-                rjson::add(shard, "SequenceNumberRange", std::move(range));
-                rjson::push_back(shards, std::move(shard));
-                
-                if (--limit == 0) {
-                    break;
-                }
-
-                last = std::nullopt;
-            }
         }
+    }
 
-        if (last) {
-            rjson::add(stream_desc, "LastEvaluatedShardId", *last);
-        }
+    if (last) {
+        rjson::add(stream_desc, "LastEvaluatedShardId", *last);
+    }
 
-        rjson::add(stream_desc, "Shards", std::move(shards));
-        rjson::add(ret, "StreamDescription", std::move(stream_desc));
-            
-        return make_ready_future<executor::request_return_type>(rjson::print(std::move(ret)));
-    });
+    rjson::add(stream_desc, "Shards", std::move(shards));
+    rjson::add(ret, "StreamDescription", std::move(stream_desc));
+        
+    co_return rjson::print(std::move(ret));
 }
 
 enum class shard_iterator_type {
@@ -898,172 +896,169 @@ future<executor::request_return_type> executor::get_records(client_state& client
     auto command = ::make_lw_shared<query::read_command>(schema->id(), schema->version(), partition_slice, _proxy.get_max_result_size(partition_slice),
             query::tombstone_limit(_proxy.get_tombstone_limit()), query::row_limit(limit * mul));
 
-    co_return co_await _proxy.query(schema, std::move(command), std::move(partition_ranges), cl, service::storage_proxy::coordinator_query_options(default_timeout(), std::move(permit), client_state)).then(
-            [this, schema, partition_slice = std::move(partition_slice), selection = std::move(selection), start_time = std::move(start_time), limit, key_names = std::move(key_names), attr_names = std::move(attr_names), type, iter, high_ts] (service::storage_proxy::coordinator_query_result qr) mutable {       
-        cql3::selection::result_set_builder builder(*selection, gc_clock::now());
-        query::result_view::consume(*qr.query_result, partition_slice, cql3::selection::result_set_builder::visitor(builder, *schema, *selection));
+    service::storage_proxy::coordinator_query_result qr = co_await _proxy.query(schema, std::move(command), std::move(partition_ranges), cl, service::storage_proxy::coordinator_query_options(default_timeout(), std::move(permit), client_state));
+    cql3::selection::result_set_builder builder(*selection, gc_clock::now());
+    query::result_view::consume(*qr.query_result, partition_slice, cql3::selection::result_set_builder::visitor(builder, *schema, *selection));
 
-        auto result_set = builder.build();
-        auto records = rjson::empty_array();
+    auto result_set = builder.build();
+    auto records = rjson::empty_array();
 
-        auto& metadata = result_set->get_metadata();
+    auto& metadata = result_set->get_metadata();
 
-        auto op_index = std::distance(metadata.get_names().begin(), 
-            std::find_if(metadata.get_names().begin(), metadata.get_names().end(), [](const lw_shared_ptr<cql3::column_specification>& cdef) {
-                return cdef->name->name() == op_column_name;
-            })
-        );
-        auto ts_index = std::distance(metadata.get_names().begin(), 
-            std::find_if(metadata.get_names().begin(), metadata.get_names().end(), [](const lw_shared_ptr<cql3::column_specification>& cdef) {
-                return cdef->name->name() == timestamp_column_name;
-            })
-        );
-        auto eor_index = std::distance(metadata.get_names().begin(), 
-            std::find_if(metadata.get_names().begin(), metadata.get_names().end(), [](const lw_shared_ptr<cql3::column_specification>& cdef) {
-                return cdef->name->name() == eor_column_name;
-            })
-        );
+    auto op_index = std::distance(metadata.get_names().begin(), 
+        std::find_if(metadata.get_names().begin(), metadata.get_names().end(), [](const lw_shared_ptr<cql3::column_specification>& cdef) {
+            return cdef->name->name() == op_column_name;
+        })
+    );
+    auto ts_index = std::distance(metadata.get_names().begin(), 
+        std::find_if(metadata.get_names().begin(), metadata.get_names().end(), [](const lw_shared_ptr<cql3::column_specification>& cdef) {
+            return cdef->name->name() == timestamp_column_name;
+        })
+    );
+    auto eor_index = std::distance(metadata.get_names().begin(), 
+        std::find_if(metadata.get_names().begin(), metadata.get_names().end(), [](const lw_shared_ptr<cql3::column_specification>& cdef) {
+            return cdef->name->name() == eor_column_name;
+        })
+    );
 
-        std::optional<utils::UUID> timestamp;
-        auto dynamodb = rjson::empty_object();
-        auto record = rjson::empty_object();
-        const auto dc_name = _proxy.get_token_metadata_ptr()->get_topology().get_datacenter();
+    std::optional<utils::UUID> timestamp;
+    auto dynamodb = rjson::empty_object();
+    auto record = rjson::empty_object();
+    const auto dc_name = _proxy.get_token_metadata_ptr()->get_topology().get_datacenter();
 
-        using op_utype = std::underlying_type_t<cdc::operation>;
+    using op_utype = std::underlying_type_t<cdc::operation>;
 
-        auto maybe_add_record = [&] {
-            if (!dynamodb.ObjectEmpty()) {
-                rjson::add(record, "dynamodb", std::move(dynamodb));
-                dynamodb = rjson::empty_object();
-            }
-            if (!record.ObjectEmpty()) {
-                rjson::add(record, "awsRegion", rjson::from_string(dc_name));
-                rjson::add(record, "eventID", event_id(iter.shard.id, *timestamp));
-                rjson::add(record, "eventSource", "scylladb:alternator");
-                rjson::add(record, "eventVersion", "1.1");
-                rjson::push_back(records, std::move(record));
-                record = rjson::empty_object();
-                --limit;
-            }
-        };
+    auto maybe_add_record = [&] {
+        if (!dynamodb.ObjectEmpty()) {
+            rjson::add(record, "dynamodb", std::move(dynamodb));
+            dynamodb = rjson::empty_object();
+        }
+        if (!record.ObjectEmpty()) {
+            rjson::add(record, "awsRegion", rjson::from_string(dc_name));
+            rjson::add(record, "eventID", event_id(iter.shard.id, *timestamp));
+            rjson::add(record, "eventSource", "scylladb:alternator");
+            rjson::add(record, "eventVersion", "1.1");
+            rjson::push_back(records, std::move(record));
+            record = rjson::empty_object();
+            --limit;
+        }
+    };
 
-        for (auto& row : result_set->rows()) {
-            auto op = static_cast<cdc::operation>(value_cast<op_utype>(data_type_for<op_utype>()->deserialize(*row[op_index])));
-            auto ts = value_cast<utils::UUID>(data_type_for<utils::UUID>()->deserialize(*row[ts_index]));
-            auto eor = row[eor_index].has_value() ? value_cast<bool>(boolean_type->deserialize(*row[eor_index])) : false;
+    for (auto& row : result_set->rows()) {
+        auto op = static_cast<cdc::operation>(value_cast<op_utype>(data_type_for<op_utype>()->deserialize(*row[op_index])));
+        auto ts = value_cast<utils::UUID>(data_type_for<utils::UUID>()->deserialize(*row[ts_index]));
+        auto eor = row[eor_index].has_value() ? value_cast<bool>(boolean_type->deserialize(*row[eor_index])) : false;
 
-            if (!dynamodb.HasMember("Keys")) {
-                auto keys = rjson::empty_object();
-                describe_single_item(*selection, row, key_names, keys);
-                rjson::add(dynamodb, "Keys", std::move(keys));
-                rjson::add(dynamodb, "ApproximateCreationDateTime", utils::UUID_gen::unix_timestamp_in_sec(ts).count());
-                rjson::add(dynamodb, "SequenceNumber", sequence_number(ts));
-                rjson::add(dynamodb, "StreamViewType", type);
-                // TODO: SizeBytes
-            }
-
-            /**
-             * We merge rows with same timestamp into a single event.
-             * This is pretty much needed, because a CDC row typically
-             * encodes ~half the info of an alternator write. 
-             * 
-             * A big, big downside to how alternator records are written
-             * (i.e. CQL), is that the distinction between INSERT and UPDATE
-             * is somewhat lost/unmappable to actual eventName. 
-             * A write (currently) always looks like an insert+modify
-             * regardless whether we wrote existing record or not. 
-             * 
-             * Maybe RMW ops could be done slightly differently so 
-             * we can distinguish them here...
-             * 
-             * For now, all writes will become MODIFY.
-             * 
-             * Note: we do not check the current pre/post
-             * flags on CDC log, instead we use data to 
-             * drive what is returned. This is (afaict)
-             * consistent with dynamo streams
-             */
-            switch (op) {
-            case cdc::operation::pre_image:
-            case cdc::operation::post_image:
-            {
-                auto item = rjson::empty_object();
-                describe_single_item(*selection, row, attr_names, item, nullptr, true);
-                describe_single_item(*selection, row, key_names, item);
-                rjson::add(dynamodb, op == cdc::operation::pre_image ? "OldImage" : "NewImage", std::move(item));
-                break;
-            }
-            case cdc::operation::update:
-                rjson::add(record, "eventName", "MODIFY");
-                break;
-            case cdc::operation::insert:
-                rjson::add(record, "eventName", "INSERT");
-                break;
-            case cdc::operation::service_row_delete:
-            case cdc::operation::service_partition_delete:
-            {
-                auto user_identity = rjson::empty_object();
-                rjson::add(user_identity, "Type", "Service");
-                rjson::add(user_identity, "PrincipalId", "dynamodb.amazonaws.com");
-                rjson::add(record, "userIdentity", std::move(user_identity));
-                rjson::add(record, "eventName", "REMOVE");
-                break;
-            }
-            default:
-                rjson::add(record, "eventName", "REMOVE");
-                break;
-            }
-            if (eor) {
-                maybe_add_record();
-                timestamp = ts;
-                if (limit == 0) {
-                    break;
-                }
-            }
+        if (!dynamodb.HasMember("Keys")) {
+            auto keys = rjson::empty_object();
+            describe_single_item(*selection, row, key_names, keys);
+            rjson::add(dynamodb, "Keys", std::move(keys));
+            rjson::add(dynamodb, "ApproximateCreationDateTime", utils::UUID_gen::unix_timestamp_in_sec(ts).count());
+            rjson::add(dynamodb, "SequenceNumber", sequence_number(ts));
+            rjson::add(dynamodb, "StreamViewType", type);
+            // TODO: SizeBytes
         }
 
-        auto ret = rjson::empty_object();
-        auto nrecords = records.Size();
-        rjson::add(ret, "Records", std::move(records));
-
-        if (nrecords != 0) {
-            // #9642. Set next iterators threshold to > last
-            shard_iterator next_iter(iter.table, iter.shard, *timestamp, false);
-            // Note that here we unconditionally return NextShardIterator,
-            // without checking if maybe we reached the end-of-shard. If the
-            // shard did end, then the next read will have nrecords == 0 and
-            // will notice end end of shard and not return NextShardIterator.
-            rjson::add(ret, "NextShardIterator", next_iter);
-            _stats.api_operations.get_records_latency.mark(std::chrono::steady_clock::now() - start_time);
-            return make_ready_future<executor::request_return_type>(rjson::print(std::move(ret)));
+        /**
+         * We merge rows with same timestamp into a single event.
+         * This is pretty much needed, because a CDC row typically
+         * encodes ~half the info of an alternator write. 
+         * 
+         * A big, big downside to how alternator records are written
+         * (i.e. CQL), is that the distinction between INSERT and UPDATE
+         * is somewhat lost/unmappable to actual eventName. 
+         * A write (currently) always looks like an insert+modify
+         * regardless whether we wrote existing record or not. 
+         * 
+         * Maybe RMW ops could be done slightly differently so 
+         * we can distinguish them here...
+         * 
+         * For now, all writes will become MODIFY.
+         * 
+         * Note: we do not check the current pre/post
+         * flags on CDC log, instead we use data to 
+         * drive what is returned. This is (afaict)
+         * consistent with dynamo streams
+         */
+        switch (op) {
+        case cdc::operation::pre_image:
+        case cdc::operation::post_image:
+        {
+            auto item = rjson::empty_object();
+            describe_single_item(*selection, row, attr_names, item, nullptr, true);
+            describe_single_item(*selection, row, key_names, item);
+            rjson::add(dynamodb, op == cdc::operation::pre_image ? "OldImage" : "NewImage", std::move(item));
+            break;
         }
-
-        // ugh. figure out if we are and end-of-shard
-        auto normal_token_owners = _proxy.get_token_metadata_ptr()->count_normal_token_owners();
-
-        return _sdks.cdc_current_generation_timestamp({ normal_token_owners }).then([this, iter, high_ts, start_time, ret = std::move(ret)](db_clock::time_point ts) mutable {
-            auto& shard = iter.shard;            
-
-            if (shard.time < ts && ts < high_ts) {
-                // The DynamoDB documentation states that when a shard is
-                // closed, reading it until the end has NextShardIterator
-                // "set to null". Our test test_streams_closed_read
-                // confirms that by "null" they meant not set at all.
-            } else {
-                // We could have return the same iterator again, but we did
-                // a search from it until high_ts and found nothing, so we
-                // can also start the next search from high_ts.
-                // TODO: but why? It's simpler just to leave the iterator be.
-                shard_iterator next_iter(iter.table, iter.shard, utils::UUID_gen::min_time_UUID(high_ts.time_since_epoch()), true);
-                rjson::add(ret, "NextShardIterator", iter);
+        case cdc::operation::update:
+            rjson::add(record, "eventName", "MODIFY");
+            break;
+        case cdc::operation::insert:
+            rjson::add(record, "eventName", "INSERT");
+            break;
+        case cdc::operation::service_row_delete:
+        case cdc::operation::service_partition_delete:
+        {
+            auto user_identity = rjson::empty_object();
+            rjson::add(user_identity, "Type", "Service");
+            rjson::add(user_identity, "PrincipalId", "dynamodb.amazonaws.com");
+            rjson::add(record, "userIdentity", std::move(user_identity));
+            rjson::add(record, "eventName", "REMOVE");
+            break;
+        }
+        default:
+            rjson::add(record, "eventName", "REMOVE");
+            break;
+        }
+        if (eor) {
+            maybe_add_record();
+            timestamp = ts;
+            if (limit == 0) {
+                break;
             }
-            _stats.api_operations.get_records_latency.mark(std::chrono::steady_clock::now() - start_time);
-            if (is_big(ret)) {
-                return make_ready_future<executor::request_return_type>(make_streamed(std::move(ret)));
-            }
-            return make_ready_future<executor::request_return_type>(rjson::print(std::move(ret)));
-        });
-    });
+        }
+    }
+
+    auto ret = rjson::empty_object();
+    auto nrecords = records.Size();
+    rjson::add(ret, "Records", std::move(records));
+
+    if (nrecords != 0) {
+        // #9642. Set next iterators threshold to > last
+        shard_iterator next_iter(iter.table, iter.shard, *timestamp, false);
+        // Note that here we unconditionally return NextShardIterator,
+        // without checking if maybe we reached the end-of-shard. If the
+        // shard did end, then the next read will have nrecords == 0 and
+        // will notice end end of shard and not return NextShardIterator.
+        rjson::add(ret, "NextShardIterator", next_iter);
+        _stats.api_operations.get_records_latency.mark(std::chrono::steady_clock::now() - start_time);
+        co_return rjson::print(std::move(ret));
+    }
+
+    // ugh. figure out if we are and end-of-shard
+    auto normal_token_owners = _proxy.get_token_metadata_ptr()->count_normal_token_owners();
+
+    db_clock::time_point ts = co_await _sdks.cdc_current_generation_timestamp({ normal_token_owners });
+    auto& shard = iter.shard;
+
+    if (shard.time < ts && ts < high_ts) {
+        // The DynamoDB documentation states that when a shard is
+        // closed, reading it until the end has NextShardIterator
+        // "set to null". Our test test_streams_closed_read
+        // confirms that by "null" they meant not set at all.
+    } else {
+        // We could have return the same iterator again, but we did
+        // a search from it until high_ts and found nothing, so we
+        // can also start the next search from high_ts.
+        // TODO: but why? It's simpler just to leave the iterator be.
+        shard_iterator next_iter(iter.table, iter.shard, utils::UUID_gen::min_time_UUID(high_ts.time_since_epoch()), true);
+        rjson::add(ret, "NextShardIterator", iter);
+    }
+    _stats.api_operations.get_records_latency.mark(std::chrono::steady_clock::now() - start_time);
+    if (is_big(ret)) {
+        co_return make_streamed(std::move(ret));
+    }
+    co_return rjson::print(std::move(ret));
 }
 
 bool executor::add_stream_options(const rjson::value& stream_specification, schema_builder& builder, service::storage_proxy& sp) {

api/api-doc/storage_service.json

@@ -3051,7 +3051,7 @@
                   },
                   {
                      "name":"incremental_mode",
-                     "description":"Set the incremental repair mode. Can be 'disabled', 'incremental', or 'full'. 'incremental': The incremental repair logic is enabled. Unrepaired sstables will be included for repair. Repaired sstables will be skipped. The incremental repair states will be updated after repair. 'full': The incremental repair logic is enabled. Both repaired and unrepaired sstables will be included for repair. The incremental repair states will be updated after repair. 'disabled': The incremental repair logic is disabled completely. The incremental repair states, e.g., repaired_at in sstables and sstables_repaired_at in the system.tablets table, will not be updated after repair. When the option is not provided, it defaults to 'disabled' mode.",
+                     "description":"Set the incremental repair mode. Can be 'disabled', 'incremental', or 'full'. 'incremental': The incremental repair logic is enabled. Unrepaired sstables will be included for repair. Repaired sstables will be skipped. The incremental repair states will be updated after repair. 'full': The incremental repair logic is enabled. Both repaired and unrepaired sstables will be included for repair. The incremental repair states will be updated after repair. 'disabled': The incremental repair logic is disabled completely. The incremental repair states, e.g., repaired_at in sstables and sstables_repaired_at in the system.tablets table, will not be updated after repair. When the option is not provided, it defaults to incremental mode.",
                      "required":false,
                      "allowMultiple":false,
                      "type":"string",

api/storage_service.cc

@@ -2016,12 +2016,14 @@ void set_snapshot(http_context& ctx, routes& r, sharded<db::snapshot_ctl>& snap_
         auto tag = req->get_query_param("tag");
         auto column_families = split(req->get_query_param("cf"), ",");
         auto sfopt = req->get_query_param("sf");
-        auto sf = db::snapshot_ctl::skip_flush(strcasecmp(sfopt.c_str(), "true") == 0);
+        db::snapshot_options opts = {
+            .skip_flush = strcasecmp(sfopt.c_str(), "true") == 0,
+        };
 
         std::vector<sstring> keynames = split(req->get_query_param("kn"), ",");
         try {
             if (column_families.empty()) {
-                co_await snap_ctl.local().take_snapshot(tag, keynames, sf);
+                co_await snap_ctl.local().take_snapshot(tag, keynames, opts);
             } else {
                 if (keynames.empty()) {
                     throw httpd::bad_param_exception("The keyspace of column families must be specified");
@@ -2029,7 +2031,7 @@ void set_snapshot(http_context& ctx, routes& r, sharded<db::snapshot_ctl>& snap_
                 if (keynames.size() > 1) {
                     throw httpd::bad_param_exception("Only one keyspace allowed when specifying a column family");
                 }
-                co_await snap_ctl.local().take_column_family_snapshot(keynames[0], column_families, tag, sf);
+                co_await snap_ctl.local().take_column_family_snapshot(keynames[0], column_families, tag, opts);
             }
             co_return json_void();
         } catch (...) {
@@ -2064,7 +2066,8 @@ void set_snapshot(http_context& ctx, routes& r, sharded<db::snapshot_ctl>& snap_
         auto info = parse_scrub_options(ctx, std::move(req));
 
         if (!info.snapshot_tag.empty()) {
-            co_await snap_ctl.local().take_column_family_snapshot(info.keyspace, info.column_families, info.snapshot_tag, db::snapshot_ctl::skip_flush::no);
+            db::snapshot_options opts = {.skip_flush = false};
+            co_await snap_ctl.local().take_column_family_snapshot(info.keyspace, info.column_families, info.snapshot_tag, opts);
         }
 
         compaction::compaction_stats stats;

api/tasks.cc

@@ -146,7 +146,8 @@ void set_tasks_compaction_module(http_context& ctx, routes& r, sharded<service::
         auto info = parse_scrub_options(ctx, std::move(req));
 
         if (!info.snapshot_tag.empty()) {
-            co_await snap_ctl.local().take_column_family_snapshot(info.keyspace, info.column_families, info.snapshot_tag, db::snapshot_ctl::skip_flush::no);
+            db::snapshot_options opts = {.skip_flush = false};
+            co_await snap_ctl.local().take_column_family_snapshot(info.keyspace, info.column_families, info.snapshot_tag, opts);
         }
 
         auto& compaction_module = db.local().get_compaction_manager().get_task_manager_module();

audit/audit.cc

@@ -209,15 +209,11 @@ future<> audit::stop_audit() {
     });
 }
 
-audit_info_ptr audit::create_audit_info(statement_category cat, const sstring& keyspace, const sstring& table) {
+audit_info_ptr audit::create_audit_info(statement_category cat, const sstring& keyspace, const sstring& table, bool batch) {
     if (!audit_instance().local_is_initialized()) {
         return nullptr;
     }
-    return std::make_unique<audit_info>(cat, keyspace, table);
-}
-
-audit_info_ptr audit::create_no_audit_info() {
-    return audit_info_ptr();
+    return std::make_unique<audit_info>(cat, keyspace, table, batch);
 }
 
 future<> audit::start(const db::config& cfg) {
@@ -267,18 +263,21 @@ future<> audit::log_login(const sstring& username, socket_address client_ip, boo
 }
 
 future<> inspect(shared_ptr<cql3::cql_statement> statement, service::query_state& query_state, const cql3::query_options& options, bool error) {
-    cql3::statements::batch_statement* batch = dynamic_cast<cql3::statements::batch_statement*>(statement.get());
-    if (batch != nullptr) {
+    auto audit_info = statement->get_audit_info();
+    if (!audit_info) {
+        return make_ready_future<>();
+    }
+    if (audit_info->batch()) {
+        cql3::statements::batch_statement* batch = static_cast<cql3::statements::batch_statement*>(statement.get());
         return do_for_each(batch->statements().begin(), batch->statements().end(), [&query_state, &options, error] (auto&& m) {
             return inspect(m.statement, query_state, options, error);
         });
     } else {
-        auto audit_info = statement->get_audit_info();
-        if (bool(audit_info) && audit::local_audit_instance().should_log(audit_info)) {
+        if (audit::local_audit_instance().should_log(audit_info)) {
             return audit::local_audit_instance().log(audit_info, query_state, options, error);
         }
+        return make_ready_future<>();
     }
-    return make_ready_future<>();
 }
 
 future<> inspect_login(const sstring& username, socket_address client_ip, bool error) {

audit/audit.hh

@@ -75,11 +75,13 @@ class audit_info final {
     sstring _keyspace;
     sstring _table;
     sstring _query;
+    bool _batch;
 public:
-    audit_info(statement_category cat, sstring keyspace, sstring table)
+    audit_info(statement_category cat, sstring keyspace, sstring table, bool batch)
         : _category(cat)
         , _keyspace(std::move(keyspace))
         , _table(std::move(table))
+        , _batch(batch)
     { }
     void set_query_string(const std::string_view& query_string) {
         _query = sstring(query_string);
@@ -89,6 +91,7 @@ public:
     const sstring& query() const { return _query; }
     sstring category_string() const;
     statement_category category() const { return _category; }
+    bool batch() const { return _batch; }
 };
 
 using audit_info_ptr = std::unique_ptr<audit_info>;
@@ -126,8 +129,7 @@ public:
     }
     static future<> start_audit(const db::config& cfg, sharded<locator::shared_token_metadata>& stm, sharded<cql3::query_processor>& qp, sharded<service::migration_manager>& mm);
     static future<> stop_audit();
-    static audit_info_ptr create_audit_info(statement_category cat, const sstring& keyspace, const sstring& table);
-    static audit_info_ptr create_no_audit_info();
+    static audit_info_ptr create_audit_info(statement_category cat, const sstring& keyspace, const sstring& table, bool batch = false);
     audit(locator::shared_token_metadata& stm,
           cql3::query_processor& qp,
           service::migration_manager& mm,

audit/audit_syslog_storage_helper.cc

@@ -53,10 +53,10 @@ static std::string json_escape(std::string_view str) {
 
 }
 
-future<> audit_syslog_storage_helper::syslog_send_helper(const sstring& msg) {
+future<> audit_syslog_storage_helper::syslog_send_helper(temporary_buffer<char> msg) {
     try {
         auto lock = co_await get_units(_semaphore, 1, std::chrono::hours(1));
-        co_await _sender.send(_syslog_address, net::packet{msg.data(), msg.size()});
+        co_await _sender.send(_syslog_address, std::span(&msg, 1));
     }
     catch (const std::exception& e) {
         auto error_msg = seastar::format(
@@ -90,7 +90,7 @@ future<> audit_syslog_storage_helper::start(const db::config& cfg) {
         co_return;
     }
 
-    co_await syslog_send_helper("Initializing syslog audit backend.");
+    co_await syslog_send_helper(temporary_buffer<char>::copy_of("Initializing syslog audit backend."));
 }
 
 future<> audit_syslog_storage_helper::stop() {
@@ -120,7 +120,7 @@ future<> audit_syslog_storage_helper::write(const audit_info* audit_info,
                                     audit_info->table(),
                                     username);
 
-    co_await syslog_send_helper(msg);
+    co_await syslog_send_helper(std::move(msg).release());
 }
 
 future<> audit_syslog_storage_helper::write_login(const sstring& username,
@@ -139,7 +139,7 @@ future<> audit_syslog_storage_helper::write_login(const sstring& username,
                                     client_ip,
                                     username);
 
-    co_await syslog_send_helper(msg.c_str());
+    co_await syslog_send_helper(std::move(msg).release());
 }
 
 }

audit/audit_syslog_storage_helper.hh

@@ -26,7 +26,7 @@ class audit_syslog_storage_helper : public storage_helper {
     net::datagram_channel _sender;
     seastar::semaphore _semaphore;
 
-    future<> syslog_send_helper(const sstring& msg);
+    future<> syslog_send_helper(seastar::temporary_buffer<char> msg);
 public:
     explicit audit_syslog_storage_helper(cql3::query_processor&, service::migration_manager&);
     virtual ~audit_syslog_storage_helper();

auth/service.cc

@@ -876,22 +876,6 @@ future<> migrate_to_auth_v2(db::system_keyspace& sys_ks, ::service::raft_group0_
                 continue; // some tables might not have been created if they were not used
             }
 
-            // use longer than usual timeout as we scan the whole table
-            // but not infinite or very long as we want to fail reasonably fast
-            const auto t = 5min;
-            const timeout_config tc{t, t, t, t, t, t, t};
-            ::service::client_state cs(::service::client_state::internal_tag{}, tc);
-            ::service::query_state qs(cs, empty_service_permit());
-
-            auto rows = co_await qp.execute_internal(
-                    seastar::format("SELECT * FROM {}.{}", meta::legacy::AUTH_KS, cf_name),
-                    db::consistency_level::ALL,
-                    qs,
-                    {},
-                    cql3::query_processor::cache_internal::no);
-            if (rows->empty()) {
-                continue;
-            }
             std::vector<sstring> col_names;
             for (const auto& col : schema->all_columns()) {
                 col_names.push_back(col.name_as_cql_string());
@@ -900,30 +884,51 @@ future<> migrate_to_auth_v2(db::system_keyspace& sys_ks, ::service::raft_group0_
             for (size_t i = 1; i < col_names.size(); ++i) {
                 val_binders_str += ", ?";
             }
-            for (const auto& row : *rows) {
-                std::vector<data_value_or_unset> values;
-                for (const auto& col : schema->all_columns()) {
-                    if (row.has(col.name_as_text())) {
-                        values.push_back(
-                                col.type->deserialize(row.get_blob_unfragmented(col.name_as_text())));
-                    } else {
-                        values.push_back(unset_value{});
+
+            std::vector<mutation> collected;
+            // use longer than usual timeout as we scan the whole table
+            // but not infinite or very long as we want to fail reasonably fast
+            const auto t = 5min;
+            const timeout_config tc{t, t, t, t, t, t, t};
+            ::service::client_state cs(::service::client_state::internal_tag{}, tc);
+            ::service::query_state qs(cs, empty_service_permit());
+
+            co_await qp.query_internal(
+                seastar::format("SELECT * FROM {}.{}", meta::legacy::AUTH_KS, cf_name),
+                db::consistency_level::ALL,
+                {},
+                1000,
+                [&qp, &cf_name, &col_names, &val_binders_str, &schema, ts, &collected] (const cql3::untyped_result_set::row& row) -> future<stop_iteration> {
+                    std::vector<data_value_or_unset> values;
+                    for (const auto& col : schema->all_columns()) {
+                        if (row.has(col.name_as_text())) {
+                            values.push_back(
+                                    col.type->deserialize(row.get_blob_unfragmented(col.name_as_text())));
+                        } else {
+                            values.push_back(unset_value{});
+                        }
                     }
-                }
-                auto muts = co_await qp.get_mutations_internal(
-                        seastar::format("INSERT INTO {}.{} ({}) VALUES ({})",
-                                db::system_keyspace::NAME,
-                                cf_name,
-                                fmt::join(col_names, ", "),
-                                val_binders_str),
-                        internal_distributed_query_state(),
-                        ts,
-                        std::move(values));
-                if (muts.size() != 1) {
-                    on_internal_error(log,
-                            format("expecting single insert mutation, got {}", muts.size()));
-                }
-                co_yield std::move(muts[0]);
+                    auto muts = co_await qp.get_mutations_internal(
+                            seastar::format("INSERT INTO {}.{} ({}) VALUES ({})",
+                                    db::system_keyspace::NAME,
+                                    cf_name,
+                                    fmt::join(col_names, ", "),
+                                    val_binders_str),
+                            internal_distributed_query_state(),
+                            ts,
+                            std::move(values));
+                    if (muts.size() != 1) {
+                        on_internal_error(log,
+                                format("expecting single insert mutation, got {}", muts.size()));
+                    }
+
+                    collected.push_back(std::move(muts[0]));
+                    co_return stop_iteration::no;
+                },
+                std::move(qs));
+
+            for (auto& m : collected) {
+                co_yield std::move(m);
             }
         }
         co_yield co_await sys_ks.make_auth_version_mutation(ts,

auth/standard_role_manager.cc

@@ -52,13 +52,6 @@ static const class_registrator<
         ::service::migration_manager&,
         cache&> registration("org.apache.cassandra.auth.CassandraRoleManager");
 
-struct record final {
-    sstring name;
-    bool is_superuser;
-    bool can_login;
-    role_set member_of;
-};
-
 static db::consistency_level consistency_for_role(std::string_view role_name) noexcept {
     if (role_name == meta::DEFAULT_SUPERUSER_NAME) {
         return db::consistency_level::QUORUM;
@@ -67,13 +60,13 @@ static db::consistency_level consistency_for_role(std::string_view role_name) no
     return db::consistency_level::LOCAL_ONE;
 }
 
-static future<std::optional<record>> find_record(cql3::query_processor& qp, std::string_view role_name) {
+future<std::optional<standard_role_manager::record>> standard_role_manager::legacy_find_record(std::string_view role_name) {
     const sstring query = seastar::format("SELECT * FROM {}.{} WHERE {} = ?",
-            get_auth_ks_name(qp),
+            get_auth_ks_name(_qp),
             meta::roles_table::name,
             meta::roles_table::role_col_name);
 
-    const auto results = co_await qp.execute_internal(
+    const auto results = co_await _qp.execute_internal(
             query,
             consistency_for_role(role_name),
             internal_distributed_query_state(),
@@ -93,8 +86,25 @@ static future<std::optional<record>> find_record(cql3::query_processor& qp, std:
                         : role_set())});
 }
 
-static future<record> require_record(cql3::query_processor& qp, std::string_view role_name) {
-    return find_record(qp, role_name).then([role_name](std::optional<record> mr) {
+future<std::optional<standard_role_manager::record>> standard_role_manager::find_record(std::string_view role_name) {
+    if (legacy_mode(_qp)) {
+        return legacy_find_record(role_name);
+    }
+    auto name = sstring(role_name);
+    auto role = _cache.get(name);
+    if (!role) {
+        return make_ready_future<std::optional<record>>(std::nullopt);
+    }
+    return make_ready_future<std::optional<record>>(std::make_optional(record{
+        .name = std::move(name),
+        .is_superuser = role->is_superuser,
+        .can_login = role->can_login,
+        .member_of = role->member_of
+    }));
+}
+
+future<standard_role_manager::record> standard_role_manager::require_record(std::string_view role_name) {
+    return find_record(role_name).then([role_name](std::optional<record> mr) {
         if (!mr) {
             throw nonexistant_role(role_name);
         }
@@ -386,7 +396,7 @@ standard_role_manager::alter(std::string_view role_name, const role_config_updat
         return fmt::to_string(fmt::join(assignments, ", "));
     };
 
-    return require_record(_qp, role_name).then([this, role_name, &u, &mc](record) {
+    return require_record(role_name).then([this, role_name, &u, &mc](record) {
         if (!u.is_superuser && !u.can_login) {
             return make_ready_future<>();
         }
@@ -620,18 +630,17 @@ standard_role_manager::revoke(std::string_view revokee_name, std::string_view ro
     });
 }
 
-static future<> collect_roles(
-        cql3::query_processor& qp,
+future<> standard_role_manager::collect_roles(
         std::string_view grantee_name,
         bool recurse,
         role_set& roles) {
-    return require_record(qp, grantee_name).then([&qp, &roles, recurse](record r) {
-        return do_with(std::move(r.member_of), [&qp, &roles, recurse](const role_set& memberships) {
-            return do_for_each(memberships.begin(), memberships.end(), [&qp, &roles, recurse](const sstring& role_name) {
+    return require_record(grantee_name).then([this, &roles, recurse](standard_role_manager::record r) {
+        return do_with(std::move(r.member_of), [this, &roles, recurse](const role_set& memberships) {
+            return do_for_each(memberships.begin(), memberships.end(), [this, &roles, recurse](const sstring& role_name) {
                 roles.insert(role_name);
 
                 if (recurse) {
-                    return collect_roles(qp, role_name, true, roles);
+                    return collect_roles(role_name, true, roles);
                 }
 
                 return make_ready_future<>();
@@ -646,7 +655,7 @@ future<role_set> standard_role_manager::query_granted(std::string_view grantee_n
     return do_with(
             role_set{sstring(grantee_name)},
             [this, grantee_name, recurse](role_set& roles) {
-        return collect_roles(_qp, grantee_name, recurse, roles).then([&roles] { return roles; });
+        return collect_roles(grantee_name, recurse, roles).then([&roles] { return roles; });
     });
 }
 
@@ -706,27 +715,21 @@ future<role_set> standard_role_manager::query_all(::service::query_state& qs) {
 }
 
 future<bool> standard_role_manager::exists(std::string_view role_name) {
-    return find_record(_qp, role_name).then([](std::optional<record> mr) {
+    return find_record(role_name).then([](std::optional<record> mr) {
         return static_cast<bool>(mr);
     });
 }
 
 future<bool> standard_role_manager::is_superuser(std::string_view role_name) {
-    return require_record(_qp, role_name).then([](record r) {
+    return require_record(role_name).then([](record r) {
         return r.is_superuser;
     });
 }
 
 future<bool> standard_role_manager::can_login(std::string_view role_name) {
-    if (legacy_mode(_qp)) {
-       const auto r = co_await require_record(_qp, role_name);
-       co_return r.can_login;
-    }
-    auto role = _cache.get(sstring(role_name));
-    if (!role) {
-        throw nonexistant_role(role_name);
-    }
-    co_return role->can_login;
+    return require_record(role_name).then([](record r) {
+        return r.can_login;
+    });
 }
 
 future<std::optional<sstring>> standard_role_manager::get_attribute(std::string_view role_name, std::string_view attribute_name, ::service::query_state& qs) {

auth/standard_role_manager.hh

@@ -90,6 +90,12 @@ public:
 
 private:
     enum class membership_change { add, remove };
+    struct record final {
+        sstring name;
+        bool is_superuser;
+        bool can_login;
+        role_set member_of;
+    };
 
     future<> create_legacy_metadata_tables_if_missing() const;
 
@@ -107,6 +113,14 @@ private:
     future<> legacy_modify_membership(std::string_view role_name, std::string_view grantee_name, membership_change);
 
     future<> modify_membership(std::string_view role_name, std::string_view grantee_name, membership_change, ::service::group0_batch& mc);
+
+    future<std::optional<record>> legacy_find_record(std::string_view role_name);
+    future<std::optional<record>> find_record(std::string_view role_name);
+    future<record> require_record(std::string_view role_name);
+    future<> collect_roles(
+            std::string_view grantee_name,
+            bool recurse,
+            role_set& roles);
 };
 
 } // namespace auth

configure.py

@@ -725,7 +725,9 @@ raft_tests = set([
 vector_search_tests = set([
     'test/vector_search/vector_store_client_test',
     'test/vector_search/load_balancer_test',
-    'test/vector_search/client_test'
+    'test/vector_search/client_test',
+    'test/vector_search/filter_test',
+    'test/vector_search/rescoring_test'
 ])
 
 vector_search_validator_bin = 'vector-search-validator/bin/vector-search-validator'
@@ -815,6 +817,9 @@ arg_parser.add_argument('--c-compiler', action='store', dest='cc', default='clan
                         help='C compiler path')
 arg_parser.add_argument('--compiler-cache', action='store', dest='compiler_cache', default='auto',
                         help='Compiler cache to use: auto (default, prefers sccache), sccache, ccache, none, or a path to a binary')
+# Workaround for https://github.com/mozilla/sccache/issues/2575
+arg_parser.add_argument('--sccache-rust', action=argparse.BooleanOptionalAction, default=False,
+                        help='Use sccache for rust code (if sccache is selected as compiler cache). Doesn\'t work with distributed builds.')
 add_tristate(arg_parser, name='dpdk', dest='dpdk', default=False,
                         help='Use dpdk (from seastar dpdk sources)')
 arg_parser.add_argument('--dpdk-target', action='store', dest='dpdk_target', default='',
@@ -945,8 +950,7 @@ scylla_core = (['message/messaging_service.cc',
                 'utils/crypt_sha512.cc',
                 'utils/logalloc.cc',
                 'utils/large_bitset.cc',
-                'utils/buffer_input_stream.cc',
-                'utils/limiting_data_source.cc',
+                'test/lib/limiting_data_source.cc',
                 'utils/updateable_value.cc',
                 'message/dictionary_service.cc',
                 'utils/directories.cc',
@@ -1034,6 +1038,9 @@ scylla_core = (['message/messaging_service.cc',
                 'cql3/functions/aggregate_fcts.cc',
                 'cql3/functions/castas_fcts.cc',
                 'cql3/functions/error_injection_fcts.cc',
+                'cql3/statements/strong_consistency/modification_statement.cc',
+                'cql3/statements/strong_consistency/select_statement.cc',
+                'cql3/statements/strong_consistency/statement_helpers.cc',
                 'cql3/functions/vector_similarity_fcts.cc',
                 'cql3/statements/cf_prop_defs.cc',
                 'cql3/statements/cf_statement.cc',
@@ -1059,8 +1066,8 @@ scylla_core = (['message/messaging_service.cc',
                 'cql3/statements/raw/parsed_statement.cc',
                 'cql3/statements/property_definitions.cc',
                 'cql3/statements/update_statement.cc',
-                'cql3/statements/strongly_consistent_modification_statement.cc',
-                'cql3/statements/strongly_consistent_select_statement.cc',
+                'cql3/statements/broadcast_modification_statement.cc',
+                'cql3/statements/broadcast_select_statement.cc',
                 'cql3/statements/delete_statement.cc',
                 'cql3/statements/prune_materialized_view_statement.cc',
                 'cql3/statements/batch_statement.cc',
@@ -1351,6 +1358,9 @@ scylla_core = (['message/messaging_service.cc',
                 'lang/wasm.cc',
                 'lang/wasm_alien_thread_runner.cc',
                 'lang/wasm_instance_cache.cc',
+                'service/strong_consistency/groups_manager.cc',
+                'service/strong_consistency/coordinator.cc',
+                'service/strong_consistency/state_machine.cc',
                 'service/raft/group0_state_id_handler.cc',
                 'service/raft/group0_state_machine.cc',
                 'service/raft/group0_state_machine_merger.cc',
@@ -1380,6 +1390,7 @@ scylla_core = (['message/messaging_service.cc',
                 'vector_search/dns.cc',
                 'vector_search/client.cc',
                 'vector_search/clients.cc',
+                'vector_search/filter.cc',
                 'vector_search/truststore.cc'
                 ] + [Antlr3Grammar('cql3/Cql.g')] \
                   + scylla_raft_core
@@ -1489,6 +1500,7 @@ idls = ['idl/gossip_digest.idl.hh',
         'idl/hinted_handoff.idl.hh',
         'idl/storage_proxy.idl.hh',
         'idl/sstables.idl.hh',
+        'idl/strong_consistency/state_machine.idl.hh',
         'idl/group0_state_machine.idl.hh',
         'idl/mapreduce_request.idl.hh',
         'idl/replica_exception.idl.hh',
@@ -1547,6 +1559,7 @@ scylla_perfs = ['test/perf/perf_alternator.cc',
                 'test/perf/perf_fast_forward.cc',
                 'test/perf/perf_row_cache_update.cc',
                 'test/perf/perf_simple_query.cc',
+                'test/perf/perf_cql_raw.cc',
                 'test/perf/perf_sstable.cc',
                 'test/perf/perf_tablets.cc',
                 'test/perf/tablet_load_balancing.cc',
@@ -1784,6 +1797,8 @@ deps['test/raft/discovery_test'] =  ['test/raft/discovery_test.cc',
 deps['test/vector_search/vector_store_client_test'] =  ['test/vector_search/vector_store_client_test.cc'] + scylla_tests_dependencies
 deps['test/vector_search/load_balancer_test'] = ['test/vector_search/load_balancer_test.cc'] + scylla_tests_dependencies
 deps['test/vector_search/client_test'] = ['test/vector_search/client_test.cc'] + scylla_tests_dependencies
+deps['test/vector_search/filter_test'] = ['test/vector_search/filter_test.cc'] + scylla_tests_dependencies
+deps['test/vector_search/rescoring_test'] = ['test/vector_search/rescoring_test.cc'] + scylla_tests_dependencies
 
 boost_tests_prefixes = ["test/boost/", "test/vector_search/", "test/raft/", "test/manual/", "test/ldap/"]
 
@@ -2393,7 +2408,7 @@ def write_build_file(f,
     # If compiler cache is available, prefix the compiler with it
     cxx_with_cache = f'{compiler_cache} {args.cxx}' if compiler_cache else args.cxx
     # For Rust, sccache is used via RUSTC_WRAPPER environment variable
-    rustc_wrapper = f'RUSTC_WRAPPER={compiler_cache} ' if compiler_cache and 'sccache' in compiler_cache else ''
+    rustc_wrapper = f'RUSTC_WRAPPER={compiler_cache} ' if compiler_cache and 'sccache' in compiler_cache and args.sccache_rust else ''
     f.write(textwrap.dedent('''\
         configure_args = {configure_args}
         builddir = {outdir}
@@ -3137,7 +3152,7 @@ def configure_using_cmake(args):
         settings['CMAKE_CXX_COMPILER_LAUNCHER'] = compiler_cache
         settings['CMAKE_C_COMPILER_LAUNCHER'] = compiler_cache
         # For Rust, sccache is used via RUSTC_WRAPPER
-        if 'sccache' in compiler_cache:
+        if 'sccache' in compiler_cache and args.sccache_rust:
             settings['Scylla_RUSTC_WRAPPER'] = compiler_cache
 
     if args.date_stamp:

cql3/CMakeLists.txt

@@ -47,6 +47,9 @@ target_sources(cql3
     functions/aggregate_fcts.cc
     functions/castas_fcts.cc
     functions/error_injection_fcts.cc
+    statements/strong_consistency/select_statement.cc
+    statements/strong_consistency/modification_statement.cc
+    statements/strong_consistency/statement_helpers.cc
     functions/vector_similarity_fcts.cc
     statements/cf_prop_defs.cc
     statements/cf_statement.cc
@@ -72,8 +75,8 @@ target_sources(cql3
     statements/raw/parsed_statement.cc
     statements/property_definitions.cc
     statements/update_statement.cc
-    statements/strongly_consistent_modification_statement.cc
-    statements/strongly_consistent_select_statement.cc
+    statements/broadcast_modification_statement.cc
+    statements/broadcast_select_statement.cc
     statements/delete_statement.cc
     statements/prune_materialized_view_statement.cc
     statements/batch_statement.cc

cql3/query_processor.cc

@@ -48,8 +48,10 @@ const std::chrono::minutes prepared_statements_cache::entry_expiry = std::chrono
 
 struct query_processor::remote {
     remote(service::migration_manager& mm, service::mapreduce_service& fwd,
-           service::storage_service& ss, service::raft_group0_client& group0_client)
+           service::storage_service& ss, service::raft_group0_client& group0_client,
+           service::strong_consistency::coordinator& _sc_coordinator)
             : mm(mm), mapreducer(fwd), ss(ss), group0_client(group0_client)
+            , sc_coordinator(_sc_coordinator)
             , gate("query_processor::remote")
     {}
 
@@ -57,6 +59,7 @@ struct query_processor::remote {
     service::mapreduce_service& mapreducer;
     service::storage_service& ss;
     service::raft_group0_client& group0_client;
+    service::strong_consistency::coordinator& sc_coordinator;
 
     seastar::named_gate gate;
 };
@@ -514,9 +517,16 @@ query_processor::~query_processor() {
     }
 }
 
+std::pair<std::reference_wrapper<service::strong_consistency::coordinator>, gate::holder>
+query_processor::acquire_strongly_consistent_coordinator() {
+    auto [remote_, holder] = remote();
+    return {remote_.get().sc_coordinator, std::move(holder)};
+}
+
 void query_processor::start_remote(service::migration_manager& mm, service::mapreduce_service& mapreducer,
-                                   service::storage_service& ss, service::raft_group0_client& group0_client) {
-    _remote = std::make_unique<struct remote>(mm, mapreducer, ss, group0_client);
+                                   service::storage_service& ss, service::raft_group0_client& group0_client,
+                                   service::strong_consistency::coordinator& sc_coordinator) {
+    _remote = std::make_unique<struct remote>(mm, mapreducer, ss, group0_client, sc_coordinator);
 }
 
 future<> query_processor::stop_remote() {
@@ -860,6 +870,7 @@ struct internal_query_state {
     sstring query_string;
     std::unique_ptr<query_options> opts;
     statements::prepared_statement::checked_weak_ptr p;
+    std::optional<service::query_state> qs;
     bool more_results = true;
 };
 
@@ -867,10 +878,14 @@ internal_query_state query_processor::create_paged_state(
         const sstring& query_string,
         db::consistency_level cl,
         const data_value_list& values,
-        int32_t page_size) {
+        int32_t page_size,
+        std::optional<service::query_state> qs) {
     auto p = prepare_internal(query_string);
     auto opts = make_internal_options(p, values, cl, page_size);
-    return internal_query_state{query_string, std::make_unique<cql3::query_options>(std::move(opts)), std::move(p), true};
+    if (!qs) {
+        qs.emplace(query_state_for_internal_call());
+    }
+    return internal_query_state{query_string, std::make_unique<cql3::query_options>(std::move(opts)), std::move(p), std::move(qs), true};
 }
 
 bool query_processor::has_more_results(cql3::internal_query_state& state) const {
@@ -893,9 +908,8 @@ future<> query_processor::for_each_cql_result(
 future<::shared_ptr<untyped_result_set>>
 query_processor::execute_paged_internal(internal_query_state& state) {
     state.p->statement->validate(*this, service::client_state::for_internal_calls());
-    auto qs = query_state_for_internal_call();
     ::shared_ptr<cql_transport::messages::result_message> msg =
-      co_await state.p->statement->execute(*this, qs, *state.opts, std::nullopt);
+      co_await state.p->statement->execute(*this, *state.qs, *state.opts, std::nullopt);
 
     class visitor : public result_message::visitor_base {
         internal_query_state& _state;
@@ -1202,8 +1216,9 @@ future<> query_processor::query_internal(
         db::consistency_level cl,
         const data_value_list& values,
         int32_t page_size,
-        noncopyable_function<future<stop_iteration>(const cql3::untyped_result_set_row&)> f) {
-    auto query_state = create_paged_state(query_string, cl, values, page_size);
+        noncopyable_function<future<stop_iteration>(const cql3::untyped_result_set_row&)> f,
+        std::optional<service::query_state> qs) {
+    auto query_state = create_paged_state(query_string, cl, values, page_size, std::move(qs));
     co_return co_await for_each_cql_result(query_state, std::move(f));
 }
 

cql3/query_processor.hh

@@ -44,6 +44,10 @@ class query_state;
 class mapreduce_service;
 class raft_group0_client;
 
+namespace strong_consistency {
+class coordinator;
+}
+
 namespace broadcast_tables {
 struct query;
 }
@@ -155,7 +159,8 @@ public:
     ~query_processor();
 
     void start_remote(service::migration_manager&, service::mapreduce_service&,
-                      service::storage_service& ss, service::raft_group0_client&);
+                      service::storage_service& ss, service::raft_group0_client&,
+                      service::strong_consistency::coordinator&);
     future<> stop_remote();
 
     data_dictionary::database db() {
@@ -174,6 +179,9 @@ public:
         return _proxy;
     }
 
+    std::pair<std::reference_wrapper<service::strong_consistency::coordinator>, gate::holder>
+    acquire_strongly_consistent_coordinator();
+
     cql_stats& get_cql_stats() {
         return _cql_stats;
     }
@@ -322,6 +330,7 @@ public:
      * page_size - maximum page size
      * f - a function to be run on each row of the query result,
      *     if the function returns stop_iteration::yes the iteration will stop
+     * qs - optional query state (default: std::nullopt)
      *
      * \note This function is optimized for convenience, not performance.
      */
@@ -330,7 +339,8 @@ public:
             db::consistency_level cl,
             const data_value_list& values,
             int32_t page_size,
-            noncopyable_function<future<stop_iteration>(const cql3::untyped_result_set_row&)> f);
+            noncopyable_function<future<stop_iteration>(const cql3::untyped_result_set_row&)> f,
+            std::optional<service::query_state> qs = std::nullopt);
 
     /*
      * \brief iterate over all cql results using paging
@@ -499,7 +509,8 @@ private:
             const sstring& query_string,
             db::consistency_level,
             const data_value_list& values,
-            int32_t page_size);
+            int32_t page_size,
+            std::optional<service::query_state> qs = std::nullopt);
 
     /*!
      * \brief run a query using paging

cql3/result_set.cc

@@ -46,6 +46,13 @@ void metadata::add_non_serialized_column(lw_shared_ptr<column_specification> nam
     _column_info->_names.emplace_back(std::move(name));
 }
 
+void metadata::hide_last_column() {
+    if (_column_info->_column_count == 0) {
+        utils::on_internal_error("Trying to hide a column when there are no columns visible.");
+    }
+    _column_info->_column_count--;
+}
+
 void metadata::set_paging_state(lw_shared_ptr<const service::pager::paging_state> paging_state) {
     _flags.set<flag::HAS_MORE_PAGES>();
     _paging_state = std::move(paging_state);

cql3/result_set.hh

@@ -73,6 +73,7 @@ public:
     uint32_t value_count() const;
 
     void add_non_serialized_column(lw_shared_ptr<column_specification> name);
+    void hide_last_column();
 
 public:
     void set_paging_state(lw_shared_ptr<const service::pager::paging_state> paging_state);

cql3/statements/alter_keyspace_statement.cc

@@ -225,10 +225,9 @@ cql3::statements::alter_keyspace_statement::prepare_schema_mutations(query_proce
             //    The second hyphen is not really true because currently topological changes can
             //    disturb it (see scylladb/scylladb#23345), but we ignore that.
             locator::assert_rf_rack_valid_keyspace(_name, tmptr, *rs);
-        } catch (const std::exception& e) {
+        } catch (const std::invalid_argument& e) {
             if (replica::database::enforce_rf_rack_validity_for_keyspace(qp.db().get_config(), *ks_md)) {
-                // There's no guarantee what the type of the exception will be, so we need to
-                // wrap it manually here in a type that can be passed to the user.
+                // wrap the exception manually here in a type that can be passed to the user.
                 throw exceptions::invalid_request_exception(e.what());
             } else {
                 // Even when RF-rack-validity is not enforced for the keyspace, we'd

cql3/statements/broadcast_modification_statement.cc

@@ -9,7 +9,7 @@
  */
 
 
-#include "cql3/statements/strongly_consistent_modification_statement.hh"
+#include "cql3/statements/broadcast_modification_statement.hh"
 
 #include <optional>
 
@@ -28,11 +28,11 @@
 
 namespace cql3 {
 
-static logging::logger logger("strongly_consistent_modification_statement");
+static logging::logger logger("broadcast_modification_statement");
 
 namespace statements {
 
-strongly_consistent_modification_statement::strongly_consistent_modification_statement(
+broadcast_modification_statement::broadcast_modification_statement(
     uint32_t bound_terms,
     schema_ptr schema,
     broadcast_tables::prepared_update query)
@@ -43,7 +43,7 @@ strongly_consistent_modification_statement::strongly_consistent_modification_sta
 { }
 
 future<::shared_ptr<cql_transport::messages::result_message>>
-strongly_consistent_modification_statement::execute(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const {
+broadcast_modification_statement::execute(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const {
     return execute_without_checking_exception_message(qp, qs, options, std::move(guard))
             .then(cql_transport::messages::propagate_exception_as_future<shared_ptr<cql_transport::messages::result_message>>);
 }
@@ -63,7 +63,7 @@ evaluate_prepared(
 }
 
 future<::shared_ptr<cql_transport::messages::result_message>>
-strongly_consistent_modification_statement::execute_without_checking_exception_message(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const {
+broadcast_modification_statement::execute_without_checking_exception_message(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const {
     if (this_shard_id() != 0) {
         co_return ::make_shared<cql_transport::messages::result_message::bounce_to_shard>(0, cql3::computed_function_values{});
     }
@@ -103,11 +103,11 @@ strongly_consistent_modification_statement::execute_without_checking_exception_m
     ), result);
 }
 
-uint32_t strongly_consistent_modification_statement::get_bound_terms() const {
+uint32_t broadcast_modification_statement::get_bound_terms() const {
     return _bound_terms;
 }
 
-future<> strongly_consistent_modification_statement::check_access(query_processor& qp, const service::client_state& state) const {
+future<> broadcast_modification_statement::check_access(query_processor& qp, const service::client_state& state) const {
     auto f = state.has_column_family_access(_schema->ks_name(), _schema->cf_name(), auth::permission::MODIFY);
     if (_query.value_condition.has_value()) {
         f = f.then([this, &state] {
@@ -117,7 +117,7 @@ future<> strongly_consistent_modification_statement::check_access(query_processo
     return f;
 }
 
-bool strongly_consistent_modification_statement::depends_on(std::string_view ks_name, std::optional<std::string_view> cf_name) const {
+bool broadcast_modification_statement::depends_on(std::string_view ks_name, std::optional<std::string_view> cf_name) const {
     return _schema->ks_name() == ks_name && (!cf_name || _schema->cf_name() == *cf_name);
 }
 

cql3/statements/broadcast_modification_statement.hh

@@ -27,13 +27,13 @@ struct prepared_update {
 
 }
 
-class strongly_consistent_modification_statement : public cql_statement_opt_metadata {
+class broadcast_modification_statement : public cql_statement_opt_metadata {
     const uint32_t _bound_terms;
     const schema_ptr _schema;
     const broadcast_tables::prepared_update _query;
 
 public:
-    strongly_consistent_modification_statement(uint32_t bound_terms, schema_ptr schema, broadcast_tables::prepared_update query);
+    broadcast_modification_statement(uint32_t bound_terms, schema_ptr schema, broadcast_tables::prepared_update query);
 
     virtual future<::shared_ptr<cql_transport::messages::result_message>>
     execute(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const override;

cql3/statements/broadcast_select_statement.cc

@@ -9,7 +9,7 @@
  */
 
 
-#include "cql3/statements/strongly_consistent_select_statement.hh"
+#include "cql3/statements/broadcast_select_statement.hh"
 
 #include <seastar/core/future.hh>
 #include <seastar/core/on_internal_error.hh>
@@ -24,7 +24,7 @@ namespace cql3 {
 
 namespace statements {
 
-static logging::logger logger("strongly_consistent_select_statement");
+static logging::logger logger("broadcast_select_statement");
 
 static
 expr::expression get_key(const cql3::expr::expression& partition_key_restrictions) {
@@ -58,7 +58,7 @@ bool is_selecting_only_value(const cql3::selection::selection& selection) {
            selection.get_columns()[0]->name() == "value";
 }
 
-strongly_consistent_select_statement::strongly_consistent_select_statement(schema_ptr schema, uint32_t bound_terms,
+broadcast_select_statement::broadcast_select_statement(schema_ptr schema, uint32_t bound_terms,
                                                                            lw_shared_ptr<const parameters> parameters,
                                                                            ::shared_ptr<selection::selection> selection,
                                                                            ::shared_ptr<const restrictions::statement_restrictions> restrictions,
@@ -73,7 +73,7 @@ strongly_consistent_select_statement::strongly_consistent_select_statement(schem
       _query{prepare_query()}
 { }
 
-broadcast_tables::prepared_select strongly_consistent_select_statement::prepare_query() const {
+broadcast_tables::prepared_select broadcast_select_statement::prepare_query() const {
     if (!is_selecting_only_value(*_selection)) {
         throw service::broadcast_tables::unsupported_operation_error("only 'value' selector is allowed");
     }
@@ -94,7 +94,7 @@ evaluate_prepared(
 }
 
 future<::shared_ptr<cql_transport::messages::result_message>>
-strongly_consistent_select_statement::execute_without_checking_exception_message(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const {
+broadcast_select_statement::execute_without_checking_exception_message(query_processor& qp, service::query_state& qs, const query_options& options, std::optional<service::group0_guard> guard) const {
     if (this_shard_id() != 0) {
         co_return ::make_shared<cql_transport::messages::result_message::bounce_to_shard>(0, cql3::computed_function_values{});
     }

cql3/statements/broadcast_select_statement.hh

@@ -25,12 +25,12 @@ struct prepared_select {
 
 }
 
-class strongly_consistent_select_statement : public select_statement {
+class broadcast_select_statement : public select_statement {
     const broadcast_tables::prepared_select _query;
 
     broadcast_tables::prepared_select prepare_query() const;
 public:
-    strongly_consistent_select_statement(schema_ptr schema,
+    broadcast_select_statement(schema_ptr schema,
                      uint32_t bound_terms,
                      lw_shared_ptr<const parameters> parameters,
                      ::shared_ptr<selection::selection> selection,

cql3/statements/create_keyspace_statement.cc

@@ -123,10 +123,9 @@ future<std::tuple<::shared_ptr<cql_transport::event::schema_change>, utils::chun
             // We hold a group0_guard, so it's correct to check this here.
             // The topology or schema cannot change while we're performing this query.
             locator::assert_rf_rack_valid_keyspace(_name, tmptr, *rs);
-        } catch (const std::exception& e) {
+        } catch (const std::invalid_argument& e) {
             if (replica::database::enforce_rf_rack_validity_for_keyspace(cfg, *ksm)) {
-                // There's no guarantee what the type of the exception will be, so we need to
-                // wrap it manually here in a type that can be passed to the user.
+                // wrap the exception in a type that can be passed to the user.
                 throw exceptions::invalid_request_exception(e.what());
             } else {
                 // Even when RF-rack-validity is not enforced for the keyspace, we'd

cql3/statements/create_table_statement.cc

@@ -31,8 +31,6 @@
 #include "db/config.hh"
 #include "compaction/time_window_compaction_strategy.hh"
 
-bool is_internal_keyspace(std::string_view name);
-
 namespace cql3 {
 
 namespace statements {
@@ -124,10 +122,6 @@ void create_table_statement::apply_properties_to(schema_builder& builder, const
         addColumnMetadataFromAliases(cfmd, Collections.singletonList(valueAlias), defaultValidator, ColumnDefinition.Kind.COMPACT_VALUE);
 #endif
 
-    if (!_properties->get_compression_options() && !is_internal_keyspace(keyspace())) {
-        builder.set_compressor_params(db.get_config().sstable_compression_user_table_options());
-    }
-
     _properties->apply_to_builder(builder, _properties->make_schema_extensions(db.extensions()), db, keyspace(), true);
 }
 

cql3/statements/ks_prop_defs.cc

@@ -98,6 +98,7 @@ static locator::replication_strategy_config_options prepare_options(
         const sstring& strategy_class,
         const locator::token_metadata& tm,
         bool rf_rack_valid_keyspaces,
+        bool enforce_rack_list,
         locator::replication_strategy_config_options options,
         const locator::replication_strategy_config_options& old_options,
         bool rack_list_enabled,
@@ -107,7 +108,7 @@ static locator::replication_strategy_config_options prepare_options(
     auto is_nts = locator::abstract_replication_strategy::to_qualified_class_name(strategy_class) == "org.apache.cassandra.locator.NetworkTopologyStrategy";
     auto is_alter = !old_options.empty();
     const auto& all_dcs = tm.get_datacenter_racks_token_owners();
-    auto auto_expand_racks = uses_tablets && rf_rack_valid_keyspaces && rack_list_enabled;
+    auto auto_expand_racks = uses_tablets && rack_list_enabled && (rf_rack_valid_keyspaces || enforce_rack_list);
 
     logger.debug("prepare_options: {}: is_nts={} auto_expand_racks={} rack_list_enabled={} old_options={} new_options={} all_dcs={}",
                  strategy_class, is_nts, auto_expand_racks, rack_list_enabled, old_options, options, all_dcs);
@@ -417,7 +418,7 @@ lw_shared_ptr<data_dictionary::keyspace_metadata> ks_prop_defs::as_ks_metadata(s
     auto initial_tablets = get_initial_tablets(default_initial_tablets, cfg.enforce_tablets());
     bool uses_tablets = initial_tablets.has_value();
     bool rack_list_enabled = utils::get_local_injector().enter("create_with_numeric") ? false : feat.rack_list_rf;
-    auto options = prepare_options(sc, tm, cfg.rf_rack_valid_keyspaces(), get_replication_options(), {}, rack_list_enabled, uses_tablets);
+    auto options = prepare_options(sc, tm, cfg.rf_rack_valid_keyspaces(), cfg.enforce_rack_list(), get_replication_options(), {}, rack_list_enabled, uses_tablets);
     return data_dictionary::keyspace_metadata::new_keyspace(ks_name, sc,
             std::move(options), initial_tablets, get_consistency_option(), get_boolean(KW_DURABLE_WRITES, true), get_storage_options());
 }
@@ -434,7 +435,7 @@ lw_shared_ptr<data_dictionary::keyspace_metadata> ks_prop_defs::as_ks_metadata_u
     auto sc = get_replication_strategy_class();
     bool rack_list_enabled = utils::get_local_injector().enter("create_with_numeric") ? false : feat.rack_list_rf;
     if (sc) {
-        options = prepare_options(*sc, tm, cfg.rf_rack_valid_keyspaces(), get_replication_options(), old_options, rack_list_enabled, uses_tablets);
+        options = prepare_options(*sc, tm, cfg.rf_rack_valid_keyspaces(), cfg.enforce_rack_list(), get_replication_options(), old_options, rack_list_enabled, uses_tablets);
     } else {
         sc = old->strategy_name();
         options = old_options;

cql3/statements/modification_statement.cc

@@ -11,7 +11,7 @@
 #include "utils/assert.hh"
 #include "cql3/cql_statement.hh"
 #include "cql3/statements/modification_statement.hh"
-#include "cql3/statements/strongly_consistent_modification_statement.hh"
+#include "cql3/statements/broadcast_modification_statement.hh"
 #include "cql3/statements/raw/modification_statement.hh"
 #include "cql3/statements/prepared_statement.hh"
 #include "cql3/expr/expr-utils.hh"
@@ -29,6 +29,8 @@
 #include "cql3/query_processor.hh"
 #include "service/storage_proxy.hh"
 #include "service/broadcast_tables/experimental/lang.hh"
+#include "cql3/statements/strong_consistency/modification_statement.hh"
+#include "cql3/statements/strong_consistency/statement_helpers.hh"
 
 #include <boost/lexical_cast.hpp>
 
@@ -546,7 +548,7 @@ modification_statement::process_where_clause(data_dictionary::database db, expr:
     }
 }
 
-::shared_ptr<strongly_consistent_modification_statement>
+::shared_ptr<broadcast_modification_statement>
 modification_statement::prepare_for_broadcast_tables() const {
     // FIXME: implement for every type of `modification_statement`.
     throw service::broadcast_tables::unsupported_operation_error{};
@@ -554,24 +556,27 @@ modification_statement::prepare_for_broadcast_tables() const {
 
 namespace raw {
 
-::shared_ptr<cql_statement_opt_metadata>
-modification_statement::prepare_statement(data_dictionary::database db, prepare_context& ctx, cql_stats& stats) {
-    ::shared_ptr<cql3::statements::modification_statement> statement = prepare(db, ctx, stats);
-
-    if (service::broadcast_tables::is_broadcast_table_statement(keyspace(), column_family())) {
-        return statement->prepare_for_broadcast_tables();
-    } else {
-        return statement;
-    }
-}
-
 std::unique_ptr<prepared_statement>
 modification_statement::prepare(data_dictionary::database db, cql_stats& stats) {
     schema_ptr schema = validation::validate_column_family(db, keyspace(), column_family());
     auto meta = get_prepare_context();
-    auto statement = prepare_statement(db, meta, stats);
+
+    auto statement = std::invoke([&] -> shared_ptr<cql_statement> {
+        auto result = prepare(db, meta, stats);
+
+        if (strong_consistency::is_strongly_consistent(db, schema->ks_name())) {
+            return ::make_shared<strong_consistency::modification_statement>(std::move(result));
+        }
+
+        if (service::broadcast_tables::is_broadcast_table_statement(keyspace(), column_family())) {
+            return result->prepare_for_broadcast_tables();
+        }
+        return result;
+    });
+
     auto partition_key_bind_indices = meta.get_partition_key_bind_indexes(*schema);
-    return std::make_unique<prepared_statement>(audit_info(), std::move(statement), meta, std::move(partition_key_bind_indices));
+    return std::make_unique<prepared_statement>(audit_info(), std::move(statement), meta, 
+        std::move(partition_key_bind_indices));
 }
 
 ::shared_ptr<cql3::statements::modification_statement>

cql3/statements/modification_statement.hh

@@ -30,7 +30,7 @@ class operation;
 
 namespace statements {
 
-class strongly_consistent_modification_statement;
+class broadcast_modification_statement;
 
 namespace raw { class modification_statement; }
 
@@ -113,15 +113,15 @@ public:
 
     virtual void add_update_for_key(mutation& m, const query::clustering_range& range, const update_parameters& params, const json_cache_opt& json_cache) const = 0;
 
-    virtual uint32_t get_bound_terms() const override;
+    uint32_t get_bound_terms() const override;
 
-    virtual const sstring& keyspace() const;
+    const sstring& keyspace() const;
 
-    virtual const sstring& column_family() const;
+    const sstring& column_family() const;
 
-    virtual bool is_counter() const;
+    bool is_counter() const;
 
-    virtual bool is_view() const;
+    bool is_view() const;
 
     int64_t get_timestamp(int64_t now, const query_options& options) const;
 
@@ -129,12 +129,12 @@ public:
 
     std::optional<gc_clock::duration> get_time_to_live(const query_options& options) const;
 
-    virtual future<> check_access(query_processor& qp, const service::client_state& state) const override;
+    future<> check_access(query_processor& qp, const service::client_state& state) const override;
 
     // Validate before execute, using client state and current schema
     void validate(query_processor&, const service::client_state& state) const override;
 
-    virtual bool depends_on(std::string_view ks_name, std::optional<std::string_view> cf_name) const override;
+    bool depends_on(std::string_view ks_name, std::optional<std::string_view> cf_name) const override;
 
     void add_operation(::shared_ptr<operation> op);
 
@@ -256,7 +256,9 @@ public:
 
     virtual json_cache_opt maybe_prepare_json_cache(const query_options& options) const;
 
-    virtual ::shared_ptr<strongly_consistent_modification_statement> prepare_for_broadcast_tables() const;
+    virtual ::shared_ptr<broadcast_modification_statement> prepare_for_broadcast_tables() const;
+
+    db::timeout_clock::duration get_timeout(const service::client_state& state, const query_options& options) const;
 
 protected:
     /**
@@ -264,9 +266,7 @@ protected:
      * processed to check that they are compatible.
      * @throws InvalidRequestException
      */
-    virtual void validate_where_clause_for_conditions() const;
-
-    db::timeout_clock::duration get_timeout(const service::client_state& state, const query_options& options) const;
+    void validate_where_clause_for_conditions() const;
 
     friend class raw::modification_statement;
 };

cql3/statements/raw/batch_statement.hh

@@ -50,8 +50,8 @@ public:
 protected:
     virtual audit::statement_category category() const override;
     virtual audit::audit_info_ptr audit_info() const override {
-        // We don't audit batch statements. Instead we audit statements that are inside the batch.
-        return audit::audit::create_no_audit_info();
+        constexpr bool batch = true;
+        return audit::audit::create_audit_info(category(), sstring(), sstring(), batch);
     }
 };
 

cql3/statements/raw/modification_statement.hh

@@ -40,7 +40,6 @@ protected:
 
 public:
     virtual std::unique_ptr<prepared_statement> prepare(data_dictionary::database db, cql_stats& stats) override;
-    ::shared_ptr<cql_statement_opt_metadata> prepare_statement(data_dictionary::database db, prepare_context& ctx, cql_stats& stats);
     ::shared_ptr<cql3::statements::modification_statement> prepare(data_dictionary::database db, prepare_context& ctx, cql_stats& stats) const;
     void add_raw(sstring&& raw) { _raw_cql = std::move(raw); }
     const sstring& get_raw_cql() const { return _raw_cql; }

cql3/statements/raw/select_statement.hh

@@ -131,8 +131,6 @@ private:
 
     void verify_ordering_is_valid(const prepared_orderings_type&, const schema&, const restrictions::statement_restrictions& restrictions) const;
 
-    prepared_ann_ordering_type prepare_ann_ordering(const schema& schema, prepare_context& ctx, data_dictionary::database db) const;
-
     // Checks whether this ordering reverses all results.
     // We only allow leaving select results unchanged or reversing them.
     bool is_ordering_reversed(const prepared_orderings_type&) const;

cql3/statements/select_statement.cc

@@ -8,6 +8,8 @@
  * SPDX-License-Identifier: (LicenseRef-ScyllaDB-Source-Available-1.0 and Apache-2.0)
  */
 
+#include "cql3/statements/strong_consistency/select_statement.hh"
+#include "cql3/statements/strong_consistency/statement_helpers.hh"
 #include "cql3/statements/select_statement.hh"
 #include "cql3/expr/expression.hh"
 #include "cql3/expr/evaluate.hh"
@@ -16,7 +18,7 @@
 #include "cql3/statements/raw/select_statement.hh"
 #include "cql3/query_processor.hh"
 #include "cql3/statements/prune_materialized_view_statement.hh"
-#include "cql3/statements/strongly_consistent_select_statement.hh"
+#include "cql3/statements/broadcast_select_statement.hh"
 
 #include "exceptions/exceptions.hh"
 #include <seastar/core/future.hh>
@@ -25,12 +27,14 @@
 #include "service/broadcast_tables/experimental/lang.hh"
 #include "service/qos/qos_common.hh"
 #include "transport/messages/result_message.hh"
+#include "cql3/functions/functions.hh"
 #include "cql3/functions/as_json_function.hh"
 #include "cql3/selection/selection.hh"
 #include "cql3/util.hh"
 #include "cql3/restrictions/statement_restrictions.hh"
 #include "index/secondary_index.hh"
 #include "types/vector.hh"
+#include "vector_search/filter.hh"
 #include "validation.hh"
 #include "exceptions/unrecognized_entity_exception.hh"
 #include <optional>
@@ -368,8 +372,9 @@ uint64_t select_statement::get_inner_loop_limit(uint64_t limit, bool is_aggregat
 }
 
 bool select_statement::needs_post_query_ordering() const {
-    // We need post-query ordering only for queries with IN on the partition key and an ORDER BY.
-    return _restrictions->key_is_in_relation() && !_parameters->orderings().empty();
+    // We need post-query ordering for queries with IN on the partition key and an ORDER BY
+    // and ANN index queries with rescoring.
+    return static_cast<bool>(_ordering_comparator);
 }
 
 struct select_statement_executor {
@@ -1958,14 +1963,46 @@ mutation_fragments_select_statement::do_execute(query_processor& qp, service::qu
             }));
 }
 
-::shared_ptr<cql3::statements::select_statement> vector_indexed_table_select_statement::prepare(data_dictionary::database db, schema_ptr schema,
-        uint32_t bound_terms, lw_shared_ptr<const parameters> parameters, ::shared_ptr<selection::selection> selection,
-        ::shared_ptr<restrictions::statement_restrictions> restrictions, ::shared_ptr<std::vector<size_t>> group_by_cell_indices, bool is_reversed,
-        ordering_comparator_type ordering_comparator, prepared_ann_ordering_type prepared_ann_ordering, std::optional<expr::expression> limit,
-        std::optional<expr::expression> per_partition_limit, cql_stats& stats, std::unique_ptr<attributes> attrs) {
+struct ann_ordering_info {
+    secondary_index::index _index;
+    raw::select_statement::prepared_ann_ordering_type _prepared_ann_ordering;
+    bool is_rescoring_enabled;
+};
+
+static std::optional<ann_ordering_info> get_ann_ordering_info(
+        data_dictionary::database db,
+        schema_ptr schema,
+        lw_shared_ptr<const raw::select_statement::parameters> parameters,
+        prepare_context& ctx) {
+
+    if (parameters->orderings().empty()) {
+        return std::nullopt;
+    }
+
+    auto [column_id, ordering] = parameters->orderings().front();
+    const auto& ann_vector = std::get_if<raw::select_statement::ann_vector>(&ordering);
+    if (!ann_vector) {
+        return std::nullopt;
+    }
+
+    ::shared_ptr<column_identifier> column = column_id->prepare_column_identifier(*schema);
+    const column_definition* def = schema->get_column_definition(column->name());
+    if (!def) {
+        throw exceptions::invalid_request_exception(
+                fmt::format("Undefined column name {}", column->text()));
+    }
+
+    if (!def->type->is_vector() || static_cast<const vector_type_impl*>(def->type.get())->get_elements_type()->get_kind() != abstract_type::kind::float_kind) {
+        throw exceptions::invalid_request_exception("ANN ordering is only supported on float vector indexes");
+    }
+
+    auto e =  expr::prepare_expression(*ann_vector, db, schema->ks_name(), nullptr, def->column_specification);
+    expr::fill_prepare_context(e, ctx);
+
+    raw::select_statement::prepared_ann_ordering_type prepared_ann_ordering = std::make_pair(std::move(def), std::move(e));
+
     auto cf = db.find_column_family(schema);
     auto& sim = cf.get_index_manager();
-    auto [index_opt, _] = restrictions->find_idx(sim);
 
     auto indexes = sim.list_indexes();
     auto it = std::find_if(indexes.begin(), indexes.end(), [&prepared_ann_ordering](const auto& ind) {
@@ -1977,27 +2014,90 @@ mutation_fragments_select_statement::do_execute(query_processor& qp, service::qu
     if (it == indexes.end()) {
         throw exceptions::invalid_request_exception("ANN ordering by vector requires the column to be indexed using 'vector_index'");
     }
-    
-    index_opt = *it;
 
-    if (!index_opt) {
-        throw std::runtime_error("No index found.");
+    return ann_ordering_info{
+        *it,
+        std::move(prepared_ann_ordering),
+        secondary_index::vector_index::is_rescoring_enabled(it->metadata().options())
+    };
+}
+
+static uint32_t add_similarity_function_to_selectors(
+        std::vector<selection::prepared_selector>& prepared_selectors,
+        const ann_ordering_info& ann_ordering_info,
+        data_dictionary::database db,
+        schema_ptr schema) {
+    auto similarity_function_name = secondary_index::vector_index::get_cql_similarity_function_name(ann_ordering_info._index.metadata().options());
+    // Create the function name
+    auto func_name = functions::function_name::native_function(sstring(similarity_function_name));
+
+    // Create the function arguments
+    std::vector<expr::expression> args;
+    args.push_back(expr::column_value(ann_ordering_info._prepared_ann_ordering.first));
+    args.push_back(ann_ordering_info._prepared_ann_ordering.second);
+
+    // Get the function object
+    std::vector<shared_ptr<assignment_testable>> provided_args;
+    provided_args.push_back(expr::as_assignment_testable(args[0], expr::type_of(args[0])));
+    provided_args.push_back(expr::as_assignment_testable(args[1], expr::type_of(args[1])));
+
+    auto func = cql3::functions::instance().get(db, schema->ks_name(), func_name, provided_args, schema->ks_name(), schema->cf_name(), nullptr);
+
+    // Create the function call expression
+    expr::function_call similarity_func_call{
+        .func = func,
+        .args = std::move(args),
+    };
+
+    // Add the similarity function as a prepared selector (last)
+    prepared_selectors.push_back(selection::prepared_selector{
+        .expr = std::move(similarity_func_call),
+        .alias = nullptr,
+    });
+    return prepared_selectors.size() - 1;
+}
+
+static select_statement::ordering_comparator_type get_similarity_ordering_comparator(std::vector<selection::prepared_selector>& prepared_selectors, uint32_t similarity_column_index) {
+    auto type = expr::type_of(prepared_selectors[similarity_column_index].expr);
+    if (type->get_kind() != abstract_type::kind::float_kind) {
+        seastar::on_internal_error(logger, "Similarity function must return float type.");
     }
+    return [similarity_column_index, type] (const raw::select_statement::result_row_type& r1, const raw::select_statement::result_row_type& r2) {
+        auto& c1 = r1[similarity_column_index];
+        auto& c2 = r2[similarity_column_index];
+        auto f1 = c1 ? value_cast<float>(type->deserialize(*c1)) : std::numeric_limits<float>::quiet_NaN();
+        auto f2 = c2 ? value_cast<float>(type->deserialize(*c2)) : std::numeric_limits<float>::quiet_NaN();
+        if (std::isfinite(f1) && std::isfinite(f2)) {
+            return f1 > f2;
+        }
+        return std::isfinite(f1);
+    };
+}
+
+::shared_ptr<cql3::statements::select_statement> vector_indexed_table_select_statement::prepare(data_dictionary::database db, schema_ptr schema,
+        uint32_t bound_terms, lw_shared_ptr<const parameters> parameters, ::shared_ptr<selection::selection> selection,
+        ::shared_ptr<restrictions::statement_restrictions> restrictions, ::shared_ptr<std::vector<size_t>> group_by_cell_indices, bool is_reversed,
+        ordering_comparator_type ordering_comparator, prepared_ann_ordering_type prepared_ann_ordering, std::optional<expr::expression> limit,
+        std::optional<expr::expression> per_partition_limit, cql_stats& stats, const secondary_index::index& index, std::unique_ptr<attributes> attrs) {
+
+    auto prepared_filter = vector_search::prepare_filter(*restrictions, parameters->allow_filtering());
 
     return ::make_shared<cql3::statements::vector_indexed_table_select_statement>(schema, bound_terms, parameters, std::move(selection), std::move(restrictions),
             std::move(group_by_cell_indices), is_reversed, std::move(ordering_comparator), std::move(prepared_ann_ordering), std::move(limit),
-            std::move(per_partition_limit), stats, *index_opt, std::move(attrs));
+            std::move(per_partition_limit), stats, index, std::move(prepared_filter), std::move(attrs));
 }
 
 vector_indexed_table_select_statement::vector_indexed_table_select_statement(schema_ptr schema, uint32_t bound_terms, lw_shared_ptr<const parameters> parameters,
         ::shared_ptr<selection::selection> selection, ::shared_ptr<const restrictions::statement_restrictions> restrictions,
         ::shared_ptr<std::vector<size_t>> group_by_cell_indices, bool is_reversed, ordering_comparator_type ordering_comparator,
         prepared_ann_ordering_type prepared_ann_ordering, std::optional<expr::expression> limit,
-        std::optional<expr::expression> per_partition_limit, cql_stats& stats, const secondary_index::index& index, std::unique_ptr<attributes> attrs)
+        std::optional<expr::expression> per_partition_limit, cql_stats& stats, const secondary_index::index& index,
+        vector_search::prepared_filter prepared_filter, std::unique_ptr<attributes> attrs)
     : select_statement{schema, bound_terms, parameters, selection, restrictions, group_by_cell_indices, is_reversed, ordering_comparator, limit,
               per_partition_limit, stats, std::move(attrs)}
     , _index{index}
-    , _prepared_ann_ordering(std::move(prepared_ann_ordering)) {
+    , _prepared_ann_ordering(std::move(prepared_ann_ordering))
+    , _prepared_filter(std::move(prepared_filter)) {
 
     if (!limit.has_value()) {
         throw exceptions::invalid_request_exception("Vector ANN queries must have a limit specified");
@@ -2032,13 +2132,19 @@ future<shared_ptr<cql_transport::messages::result_message>> vector_indexed_table
 
         auto timeout = db::timeout_clock::now() + get_timeout(state.get_client_state(), options);
         auto aoe = abort_on_expiry(timeout);
+        auto filter_json = _prepared_filter.to_json(options);
+        uint64_t fetch = static_cast<uint64_t>(std::ceil(limit * secondary_index::vector_index::get_oversampling(_index.metadata().options())));
         auto pkeys = co_await qp.vector_store_client().ann(
-                _schema->ks_name(), _index.metadata().name(), _schema, get_ann_ordering_vector(options), limit, aoe.abort_source());
+                _schema->ks_name(), _index.metadata().name(), _schema, get_ann_ordering_vector(options), fetch, filter_json, aoe.abort_source());
         if (!pkeys.has_value()) {
             co_await coroutine::return_exception(
                     exceptions::invalid_request_exception(std::visit(vector_search::vector_store_client::ann_error_visitor{}, pkeys.error())));
         }
 
+        if (pkeys->size() > limit && !secondary_index::vector_index::is_rescoring_enabled(_index.metadata().options())) {
+            pkeys->erase(pkeys->begin() + limit, pkeys->end());
+        }
+
         co_return co_await query_base_table(qp, state, options, pkeys.value(), timeout);
     });
 
@@ -2055,11 +2161,11 @@ void vector_indexed_table_select_statement::update_stats() const {
 }
 
 lw_shared_ptr<query::read_command> vector_indexed_table_select_statement::prepare_command_for_base_query(
-        query_processor& qp, service::query_state& state, const query_options& options) const {
+        query_processor& qp, service::query_state& state, const query_options& options, uint64_t fetch_limit) const {
     auto slice = make_partition_slice(options);
     return ::make_lw_shared<query::read_command>(_schema->id(), _schema->version(), std::move(slice), qp.proxy().get_max_result_size(slice),
             query::tombstone_limit(qp.proxy().get_tombstone_limit()),
-            query::row_limit(get_inner_loop_limit(get_limit(options, _limit), _selection->is_aggregate())), query::partition_limit(query::max_partitions),
+            query::row_limit(get_inner_loop_limit(fetch_limit, _selection->is_aggregate())), query::partition_limit(query::max_partitions),
             _query_start_time_point, tracing::make_trace_info(state.get_trace_state()), query_id::create_null_id(), query::is_first_page::no,
             options.get_timestamp(state));
 }
@@ -2077,7 +2183,7 @@ std::vector<float> vector_indexed_table_select_statement::get_ann_ordering_vecto
 future<::shared_ptr<cql_transport::messages::result_message>> vector_indexed_table_select_statement::query_base_table(query_processor& qp,
         service::query_state& state, const query_options& options, const std::vector<vector_search::primary_key>& pkeys,
         lowres_clock::time_point timeout) const {
-    auto command = prepare_command_for_base_query(qp, state, options);
+    auto command = prepare_command_for_base_query(qp, state, options, pkeys.size());
 
     // For tables without clustering columns, we can optimize by querying
     // partition ranges instead of individual primary keys, since the
@@ -2116,6 +2222,7 @@ future<::shared_ptr<cql_transport::messages::result_message>> vector_indexed_tab
             query::result_merger{command->get_row_limit(), query::max_partitions});
 
     co_return co_await wrap_result_to_error_message([this, &command, &options](auto result) {
+        command->set_row_limit(get_limit(options, _limit));
         return process_results(std::move(result), command, options, _query_start_time_point);
     })(std::move(result));
 }
@@ -2129,6 +2236,7 @@ future<::shared_ptr<cql_transport::messages::result_message>> vector_indexed_tab
                     {timeout, state.get_permit(), state.get_client_state(), state.get_trace_state(), {}, {}, options.get_specific_options().node_local_only},
                     std::nullopt)
             .then(wrap_result_to_error_message([this, &options, command](service::storage_proxy::coordinator_query_result qr) {
+                command->set_row_limit(get_limit(options, _limit));
                 return this->process_results(std::move(qr.query_result), command, options, _query_start_time_point);
             }));
 }
@@ -2223,32 +2331,41 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
 
     prepared_selectors = maybe_jsonize_select_clause(std::move(prepared_selectors), db, schema);
 
-    auto aggregation_depth = 0u;
+    std::optional<ann_ordering_info> ann_ordering_info_opt = get_ann_ordering_info(db, schema, _parameters, ctx);
+    bool is_ann_query = ann_ordering_info_opt.has_value();
 
-    // Force aggregation if GROUP BY is used. This will wrap every column x as first(x).
-    if (!_group_by_columns.empty()) {
-        aggregation_depth = std::max(aggregation_depth, 1u);
-        if (prepared_selectors.empty()) {
-            // We have a "SELECT * GROUP BY". If we leave prepared_selectors
-            // empty, below we choose selection::wildcard() for SELECT *, and
-            // forget to do the "levellize" trick needed for the GROUP BY.
-            // So we need to set prepared_selectors. See #16531.
-            auto all_columns = selection::selection::wildcard_columns(schema);
-            std::vector<::shared_ptr<selection::raw_selector>> select_all;
-            select_all.reserve(all_columns.size());
-            for (const column_definition *cdef : all_columns) {
-                auto name = ::make_shared<cql3::column_identifier::raw>(cdef->name_as_text(), true);
-                select_all.push_back(::make_shared<selection::raw_selector>(
-                    expr::unresolved_identifier(std::move(name)), nullptr));
-            }
-            prepared_selectors = selection::raw_selector::to_prepared_selectors(select_all, *schema, db, keyspace());
+    if (prepared_selectors.empty() && (!_group_by_columns.empty() || (is_ann_query && ann_ordering_info_opt->is_rescoring_enabled))) {
+        // We have a "SELECT * GROUP BY" or "SELECT * ORDER BY ANN" with rescoring enabled. If we leave prepared_selectors
+        // empty, below we choose selection::wildcard() for SELECT *, and either:
+        //  - forget to do the "levellize" trick needed for the GROUP BY. See #16531.
+        //  - forget to add the similarity function needed for ORDER BY ANN with rescoring. See below.
+        // So we need to set prepared_selectors. 
+        auto all_columns = selection::selection::wildcard_columns(schema);
+        std::vector<::shared_ptr<selection::raw_selector>> select_all;
+        select_all.reserve(all_columns.size());
+        for (const column_definition *cdef : all_columns) {
+            auto name = ::make_shared<cql3::column_identifier::raw>(cdef->name_as_text(), true);
+            select_all.push_back(::make_shared<selection::raw_selector>(
+                expr::unresolved_identifier(std::move(name)), nullptr));
         }
+        prepared_selectors = selection::raw_selector::to_prepared_selectors(select_all, *schema, db, keyspace());
     }
 
     for (auto& ps : prepared_selectors) {
         expr::fill_prepare_context(ps.expr, ctx);
     }
 
+    // Force aggregation if GROUP BY is used. This will wrap every column x as first(x).
+    auto aggregation_depth = _group_by_columns.empty() ? 0u : 1u;
+
+    select_statement::ordering_comparator_type ordering_comparator;
+    bool hide_last_column = false;
+    if (is_ann_query && ann_ordering_info_opt->is_rescoring_enabled) {
+        uint32_t similarity_column_index = add_similarity_function_to_selectors(prepared_selectors, *ann_ordering_info_opt, db, schema);
+        hide_last_column = true;
+        ordering_comparator = get_similarity_ordering_comparator(prepared_selectors, similarity_column_index);
+    }
+
     for (auto& ps : prepared_selectors) {
         aggregation_depth = std::max(aggregation_depth, expr::aggregation_depth(ps.expr));
     }
@@ -2266,6 +2383,11 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
                      ? selection::selection::wildcard(schema)
                      : selection::selection::from_selectors(db, schema, keyspace(), levellized_prepared_selectors);
 
+    if (is_ann_query && hide_last_column) {
+        // Hide the similarity selector from the client by reducing column_count
+        selection->get_result_metadata()->hide_last_column();
+    }
+
     // Cassandra 5.0.2 disallows PER PARTITION LIMIT with aggregate queries
     // but only if GROUP BY is not used.
     // See #9879 for more details.
@@ -2273,8 +2395,6 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
         throw exceptions::invalid_request_exception("PER PARTITION LIMIT is not allowed with aggregate queries.");
     }
 
-    bool is_ann_query = !_parameters->orderings().empty() && std::holds_alternative<select_statement::ann_vector>(_parameters->orderings().front().second);
-
     auto restrictions = prepare_restrictions(db, schema, ctx, selection, for_view, _parameters->allow_filtering() || is_ann_query,
             restrictions::check_indexes(!_parameters->is_mutation_fragments()));
 
@@ -2282,19 +2402,14 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
         validate_distinct_selection(*schema, *selection, *restrictions);
     }
 
-    select_statement::ordering_comparator_type ordering_comparator;
     bool is_reversed_ = false;
 
-    std::optional<prepared_ann_ordering_type> prepared_ann_ordering;
-
     auto orderings = _parameters->orderings();
 
-    if (!orderings.empty()) {
+    if (!orderings.empty() && !is_ann_query) {
         std::visit([&](auto&& ordering) {
             using T = std::decay_t<decltype(ordering)>;
-            if constexpr (std::is_same_v<T, select_statement::ann_vector>) {
-                prepared_ann_ordering = prepare_ann_ordering(*schema, ctx, db);
-            } else {
+            if constexpr (!std::is_same_v<T, select_statement::ann_vector>) {
                 SCYLLA_ASSERT(!for_view);
                 verify_ordering_is_allowed(*_parameters, *restrictions);
                 prepared_orderings_type prepared_orderings = prepare_orderings(*schema);
@@ -2307,7 +2422,7 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
     }
 
     std::vector<sstring> warnings;
-    if (!prepared_ann_ordering.has_value()) {
+    if (!is_ann_query) {
         check_needs_filtering(*restrictions, db.get_config().strict_allow_filtering(), warnings);
         ensure_filtering_columns_retrieval(db, *selection, *restrictions);
     }
@@ -2361,7 +2476,21 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
                 && restrictions->partition_key_restrictions_size() == schema->partition_key_size());
     };
 
-    if (_parameters->is_prune_materialized_view()) {
+    if (strong_consistency::is_strongly_consistent(db, schema->ks_name())) {
+        stmt = ::make_shared<strong_consistency::select_statement>(
+                schema,
+                ctx.bound_variables_size(),
+                _parameters,
+                std::move(selection),
+                std::move(restrictions),
+                std::move(group_by_cell_indices),
+                is_reversed_,
+                std::move(ordering_comparator),
+                prepare_limit(db, ctx, _limit),
+                prepare_limit(db, ctx, _per_partition_limit),
+                stats,
+                std::move(prepared_attrs));
+    } else if (_parameters->is_prune_materialized_view()) {
         stmt = ::make_shared<cql3::statements::prune_materialized_view_statement>(
                 schema,
                 ctx.bound_variables_size(),
@@ -2390,10 +2519,10 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
                 prepare_limit(db, ctx, _per_partition_limit),
                 stats,
                 std::move(prepared_attrs));
-    } else if (prepared_ann_ordering) {
+    } else if (is_ann_query) {
         stmt = vector_indexed_table_select_statement::prepare(db, schema, ctx.bound_variables_size(), _parameters, std::move(selection), std::move(restrictions),
-                std::move(group_by_cell_indices), is_reversed_, std::move(ordering_comparator), std::move(*prepared_ann_ordering),
-                prepare_limit(db, ctx, _limit), prepare_limit(db, ctx, _per_partition_limit), stats, std::move(prepared_attrs));
+                std::move(group_by_cell_indices), is_reversed_, std::move(ordering_comparator), std::move(ann_ordering_info_opt->_prepared_ann_ordering),
+                prepare_limit(db, ctx, _limit), prepare_limit(db, ctx, _per_partition_limit), stats, ann_ordering_info_opt->_index, std::move(prepared_attrs));
     } else if (restrictions->uses_secondary_indexing()) {
         stmt = view_indexed_table_select_statement::prepare(
                 db,
@@ -2425,7 +2554,7 @@ std::unique_ptr<prepared_statement> select_statement::prepare(data_dictionary::d
             std::move(prepared_attrs)
         );
     } else if (service::broadcast_tables::is_broadcast_table_statement(keyspace(), column_family())) {
-        stmt = ::make_shared<cql3::statements::strongly_consistent_select_statement>(
+        stmt = ::make_shared<cql3::statements::broadcast_select_statement>(
                 schema,
                 ctx.bound_variables_size(),
                 _parameters,
@@ -2615,28 +2744,6 @@ void select_statement::verify_ordering_is_valid(const prepared_orderings_type& o
     }
 }
 
-select_statement::prepared_ann_ordering_type select_statement::prepare_ann_ordering(const schema& schema, prepare_context& ctx, data_dictionary::database db) const {
-    auto [column_id, ordering] = _parameters->orderings().front();
-    const auto& ann_vector = std::get_if<select_statement::ann_vector>(&ordering);
-    SCYLLA_ASSERT(ann_vector);
-
-    ::shared_ptr<column_identifier> column = column_id->prepare_column_identifier(schema);
-    const column_definition* def = schema.get_column_definition(column->name());
-    if (!def) {
-        throw exceptions::invalid_request_exception(
-                fmt::format("Undefined column name {}", column->text()));
-    }
-
-    if (!def->type->is_vector() || static_cast<const vector_type_impl*>(def->type.get())->get_elements_type()->get_kind() != abstract_type::kind::float_kind) {
-        throw exceptions::invalid_request_exception("ANN ordering is only supported on float vector indexes");
-    }
-
-    auto e =  expr::prepare_expression(*ann_vector, db, keyspace(), nullptr, def->column_specification);
-    expr::fill_prepare_context(e, ctx);
-
-    return std::make_pair(std::move(def), std::move(e));
-}
-
 select_statement::ordering_comparator_type select_statement::get_ordering_comparator(const prepared_orderings_type& orderings,
     selection::selection& selection,
     const restrictions::statement_restrictions& restrictions) {

cql3/statements/select_statement.hh

@@ -22,6 +22,7 @@
 #include "locator/host_id.hh"
 #include "service/cas_shard.hh"
 #include "vector_search/vector_store_client.hh"
+#include "vector_search/filter.hh"
 
 namespace service {
     class client_state;
@@ -362,6 +363,7 @@ private:
 class vector_indexed_table_select_statement : public select_statement {
     secondary_index::index _index;
     prepared_ann_ordering_type _prepared_ann_ordering;
+    vector_search::prepared_filter _prepared_filter;
     mutable gc_clock::time_point _query_start_time_point;
 
 public:
@@ -371,13 +373,13 @@ public:
             lw_shared_ptr<const parameters> parameters, ::shared_ptr<selection::selection> selection,
             ::shared_ptr<restrictions::statement_restrictions> restrictions, ::shared_ptr<std::vector<size_t>> group_by_cell_indices, bool is_reversed,
             ordering_comparator_type ordering_comparator, prepared_ann_ordering_type prepared_ann_ordering, std::optional<expr::expression> limit,
-            std::optional<expr::expression> per_partition_limit, cql_stats& stats, std::unique_ptr<cql3::attributes> attrs);
+            std::optional<expr::expression> per_partition_limit, cql_stats& stats, const secondary_index::index& index, std::unique_ptr<cql3::attributes> attrs);
 
     vector_indexed_table_select_statement(schema_ptr schema, uint32_t bound_terms, lw_shared_ptr<const parameters> parameters,
             ::shared_ptr<selection::selection> selection, ::shared_ptr<const restrictions::statement_restrictions> restrictions,
             ::shared_ptr<std::vector<size_t>> group_by_cell_indices, bool is_reversed, ordering_comparator_type ordering_comparator,
             prepared_ann_ordering_type prepared_ann_ordering, std::optional<expr::expression> limit, std::optional<expr::expression> per_partition_limit,
-            cql_stats& stats, const secondary_index::index& index, std::unique_ptr<cql3::attributes> attrs);
+            cql_stats& stats, const secondary_index::index& index, vector_search::prepared_filter prepared_filter, std::unique_ptr<cql3::attributes> attrs);
 
 private:
     future<::shared_ptr<cql_transport::messages::result_message>> do_execute(
@@ -385,7 +387,7 @@ private:
 
     void update_stats() const;
 
-    lw_shared_ptr<query::read_command> prepare_command_for_base_query(query_processor& qp, service::query_state& state, const query_options& options) const;
+    lw_shared_ptr<query::read_command> prepare_command_for_base_query(query_processor& qp, service::query_state& state, const query_options& options, uint64_t fetch_limit) const;
 
     std::vector<float> get_ann_ordering_vector(const query_options& options) const;
 

cql3/statements/strong_consistency/modification_statement.cc

@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2025-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
+ */
+
+#include "modification_statement.hh"
+
+#include "transport/messages/result_message.hh"
+#include "cql3/query_processor.hh"
+#include "service/strong_consistency/coordinator.hh"
+#include "cql3/statements/strong_consistency/statement_helpers.hh"
+
+namespace cql3::statements::strong_consistency {
+static logging::logger logger("sc_modification_statement");
+
+modification_statement::modification_statement(shared_ptr<base_statement> statement)
+    : cql_statement_opt_metadata(&timeout_config::write_timeout)
+    , _statement(std::move(statement))
+{
+}
+
+using result_message = cql_transport::messages::result_message;
+
+future<shared_ptr<result_message>> modification_statement::execute(query_processor& qp, service::query_state& qs, 
+    const query_options& options, std::optional<service::group0_guard> guard) const
+{
+    return execute_without_checking_exception_message(qp, qs, options, std::move(guard))
+            .then(cql_transport::messages::propagate_exception_as_future<shared_ptr<result_message>>);
+}
+
+future<shared_ptr<result_message>> modification_statement::execute_without_checking_exception_message(
+        query_processor& qp, service::query_state& qs, const query_options& options,
+        std::optional<service::group0_guard> guard) const
+{
+    auto json_cache = base_statement::json_cache_opt{};
+    const auto keys = _statement->build_partition_keys(options, json_cache);
+    if (keys.size() != 1 || !query::is_single_partition(keys[0])) {
+        throw exceptions::invalid_request_exception("Strongly consistent queries can only target a single partition");
+    }
+    if (_statement->requires_read()) {
+        throw exceptions::invalid_request_exception("Strongly consistent updates don't support data prefetch");
+    }
+
+    auto [coordinator, holder] = qp.acquire_strongly_consistent_coordinator();
+    const auto mutate_result = co_await coordinator.get().mutate(_statement->s,
+        keys[0].start()->value().token(),
+        [&](api::timestamp_type ts) {
+            const auto prefetch_data = update_parameters::prefetch_data(_statement->s);
+            const auto ttl = _statement->get_time_to_live(options);
+            const auto params = update_parameters(_statement->s, options, ts, ttl, prefetch_data);
+            const auto ranges = _statement->create_clustering_ranges(options, json_cache);
+            auto muts = _statement->apply_updates(keys, ranges, params, json_cache);
+            if (muts.size() != 1) {
+                on_internal_error(logger, ::format("statement '{}' has unexpected number of mutations {}",
+                    raw_cql_statement, muts.size()));
+            }
+            return std::move(*muts.begin());
+        });
+
+    using namespace service::strong_consistency;
+    if (const auto* redirect = get_if<need_redirect>(&mutate_result)) {
+        co_return co_await redirect_statement(qp, options, redirect->target);
+    }
+
+    co_return seastar::make_shared<result_message::void_message>();
+}
+
+future<> modification_statement::check_access(query_processor& qp, const service::client_state& state) const {
+    return _statement->check_access(qp, state);
+}
+
+uint32_t modification_statement::get_bound_terms() const {
+    return _statement->get_bound_terms();
+}
+
+bool modification_statement::depends_on(std::string_view ks_name, std::optional<std::string_view> cf_name) const {
+    return _statement->depends_on(ks_name, cf_name);
+}
+}

cql3/statements/strong_consistency/modification_statement.hh

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2025-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
+ */
+
+#pragma once
+
+#include "cql3/cql_statement.hh"
+#include "cql3/expr/expression.hh"
+#include "cql3/statements/modification_statement.hh"
+
+namespace cql3::statements::strong_consistency {
+
+class modification_statement : public cql_statement_opt_metadata {
+    using result_message = cql_transport::messages::result_message;
+    using base_statement = cql3::statements::modification_statement;
+
+    shared_ptr<base_statement> _statement;
+public:
+    modification_statement(shared_ptr<base_statement> statement);
+
+    future<shared_ptr<result_message>> execute(query_processor& qp, service::query_state& state,
+        const query_options& options, std::optional<service::group0_guard> guard) const override;
+
+    future<shared_ptr<result_message>> execute_without_checking_exception_message(query_processor& qp,
+        service::query_state& qs, const query_options& options,
+        std::optional<service::group0_guard> guard) const override;
+
+    future<> check_access(query_processor& qp, const service::client_state& state) const override;
+
+    uint32_t get_bound_terms() const override;
+
+    bool depends_on(std::string_view ks_name, std::optional<std::string_view> cf_name) const override;
+};
+
+}

cql3/statements/strong_consistency/select_statement.cc

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2025-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
+ */
+
+#include "select_statement.hh"
+
+#include "query/query-request.hh"
+#include "cql3/query_processor.hh"
+#include "service/strong_consistency/coordinator.hh"
+#include "cql3/statements/strong_consistency/statement_helpers.hh"
+
+namespace cql3::statements::strong_consistency {
+
+using result_message = cql_transport::messages::result_message;
+
+future<::shared_ptr<result_message>> select_statement::do_execute(query_processor& qp,
+        service::query_state& state, 
+        const query_options& options) const
+{
+    const auto key_ranges = _restrictions->get_partition_key_ranges(options);
+    if (key_ranges.size() != 1 || !query::is_single_partition(key_ranges[0])) {
+        throw exceptions::invalid_request_exception("Strongly consistent queries can only target a single partition");
+    }
+    const auto now = gc_clock::now();
+    auto read_command = make_lw_shared<query::read_command>(
+        _query_schema->id(),
+        _query_schema->version(),
+        make_partition_slice(options),
+        query::max_result_size(query::result_memory_limiter::maximum_result_size),
+        query::tombstone_limit(query::tombstone_limit::max),
+        query::row_limit(get_inner_loop_limit(get_limit(options, _limit), _selection->is_aggregate())),
+        query::partition_limit(query::max_partitions),
+        now,
+        tracing::make_trace_info(state.get_trace_state()),
+        query_id::create_null_id(),
+        query::is_first_page::no,
+        options.get_timestamp(state));
+    const auto timeout = db::timeout_clock::now() + get_timeout(state.get_client_state(), options);
+    auto [coordinator, holder] = qp.acquire_strongly_consistent_coordinator();
+    auto query_result = co_await coordinator.get().query(_query_schema, *read_command,
+        key_ranges, state.get_trace_state(), timeout);
+
+    using namespace service::strong_consistency;
+    if (const auto* redirect = get_if<need_redirect>(&query_result)) {
+        co_return co_await redirect_statement(qp, options, redirect->target);
+    }
+
+    co_return co_await process_results(get<lw_shared_ptr<query::result>>(std::move(query_result)),
+        read_command, options, now);
+}
+
+}

cql3/statements/strong_consistency/select_statement.hh

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2025-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
+ */
+
+#pragma once
+
+#include "cql3/cql_statement.hh"
+#include "cql3/statements/select_statement.hh"
+
+namespace cql3::statements::strong_consistency {
+
+class select_statement : public cql3::statements::select_statement {
+    using result_message = cql_transport::messages::result_message;
+
+public:
+    using cql3::statements::select_statement::select_statement;
+
+    future<::shared_ptr<cql_transport::messages::result_message>> do_execute(query_processor& qp,
+        service::query_state& state, const query_options& options) const override;
+};
+
+}

cql3/statements/strong_consistency/statement_helpers.cc

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2025-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
+ */
+
+#include "statement_helpers.hh"
+
+#include "transport/messages/result_message_base.hh"
+#include "cql3/query_processor.hh"
+#include "replica/database.hh"
+#include "locator/tablet_replication_strategy.hh"
+
+namespace cql3::statements::strong_consistency {
+future<::shared_ptr<cql_transport::messages::result_message>> redirect_statement(query_processor& qp,
+        const query_options& options,
+        const locator::tablet_replica& target)
+{
+    const auto my_host_id = qp.db().real_database().get_token_metadata().get_topology().my_host_id();
+    if (target.host != my_host_id) {
+        throw exceptions::invalid_request_exception(format(
+            "Strongly consistent writes can be executed only on the leader node, "
+            "leader id {}, current host id {}",
+            target.host, my_host_id));
+    }
+    auto&& func_values_cache = const_cast<cql3::query_options&>(options).take_cached_pk_function_calls();
+    co_return qp.bounce_to_shard(target.shard, std::move(func_values_cache));
+}
+
+bool is_strongly_consistent(data_dictionary::database db, std::string_view ks_name) {
+    const auto* tablet_aware_rs = db.find_keyspace(ks_name).get_replication_strategy().maybe_as_tablet_aware();
+    return tablet_aware_rs && tablet_aware_rs->get_consistency() != data_dictionary::consistency_config_option::eventual;
+}
+
+}

cql3/statements/strong_consistency/statement_helpers.hh

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2025-present ScyllaDB
+ */
+
+/*
+ * SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
+ */
+
+#pragma once
+
+#include "cql3/cql_statement.hh"
+#include "locator/tablets.hh"
+
+namespace cql3::statements::strong_consistency {
+
+future<::shared_ptr<cql_transport::messages::result_message>> redirect_statement(
+    query_processor& qp,
+    const query_options& options,
+    const locator::tablet_replica& target);
+
+bool is_strongly_consistent(data_dictionary::database db, std::string_view ks_name);
+
+}

cql3/statements/update_statement.cc

@@ -13,7 +13,7 @@
 #include "cql3/expr/expression.hh"
 #include "cql3/expr/evaluate.hh"
 #include "cql3/expr/expr-utils.hh"
-#include "cql3/statements/strongly_consistent_modification_statement.hh"
+#include "cql3/statements/broadcast_modification_statement.hh"
 #include "service/broadcast_tables/experimental/lang.hh"
 #include "raw/update_statement.hh"
 
@@ -333,7 +333,7 @@ std::optional<expr::expression> get_value_condition(const expr::expression& the_
     return binop->rhs;
 }
 
-::shared_ptr<strongly_consistent_modification_statement>
+::shared_ptr<broadcast_modification_statement>
 update_statement::prepare_for_broadcast_tables() const {
     if (attrs) {
         if (attrs->is_time_to_live_set()) {
@@ -359,7 +359,7 @@ update_statement::prepare_for_broadcast_tables() const {
         .value_condition = get_value_condition(_condition),
     };
 
-    return ::make_shared<strongly_consistent_modification_statement>(
+    return ::make_shared<broadcast_modification_statement>(
         get_bound_terms(),
         s,
         query

cql3/statements/update_statement.hh

@@ -45,7 +45,7 @@ private:
     virtual void execute_operations_for_key(mutation& m, const clustering_key_prefix& prefix, const update_parameters& params, const json_cache_opt& json_cache) const;
 
 public:
-    virtual ::shared_ptr<strongly_consistent_modification_statement> prepare_for_broadcast_tables() const override;
+    virtual ::shared_ptr<broadcast_modification_statement> prepare_for_broadcast_tables() const override;
 };
 
 /*

db/cache_mutation_reader.hh

@@ -323,6 +323,9 @@ void cache_mutation_reader::touch_partition() {
 
 inline
 future<> cache_mutation_reader::fill_buffer() {
+    if (const auto& ex = get_abort_exception(); ex) {
+        return make_exception_future<>(ex);
+    }
     if (_state == state::before_static_row) {
         touch_partition();
         auto after_static_row = [this] {

db/config.cc

@@ -621,25 +621,6 @@ db::config::config(std::shared_ptr<db::extensions> exts)
     * @GroupDescription: Provides an overview of the group.
     */
     /**
-    * @Group Ungrouped properties
-    */
-    , background_writer_scheduling_quota(this, "background_writer_scheduling_quota", value_status::Deprecated, 1.0,
-        "max cpu usage ratio (between 0 and 1) for compaction process. Not intended for setting in normal operations. Setting it to 1 or higher will disable it, recommended operational setting is 0.5.")
-    , auto_adjust_flush_quota(this, "auto_adjust_flush_quota", value_status::Deprecated, false,
-        "true: auto-adjust memtable shares for flush processes")
-    , memtable_flush_static_shares(this, "memtable_flush_static_shares", liveness::LiveUpdate, value_status::Used, 0,
-        "If set to higher than 0, ignore the controller's output and set the memtable shares statically. Do not set this unless you know what you are doing and suspect a problem in the controller. This option will be retired when the controller reaches more maturity.")
-    , compaction_static_shares(this, "compaction_static_shares", liveness::LiveUpdate, value_status::Used, 0,
-        "If set to higher than 0, ignore the controller's output and set the compaction shares statically. Do not set this unless you know what you are doing and suspect a problem in the controller. This option will be retired when the controller reaches more maturity.")
-    , compaction_max_shares(this, "compaction_max_shares", liveness::LiveUpdate, value_status::Used, default_compaction_maximum_shares,
-        "Set the maximum shares of regular compaction to the specific value. Do not set this unless you know what you are doing and suspect a problem in the controller. This option will be retired when the controller reaches more maturity.")
-    , compaction_enforce_min_threshold(this, "compaction_enforce_min_threshold", liveness::LiveUpdate, value_status::Used, false,
-        "If set to true, enforce the min_threshold option for compactions strictly. If false (default), Scylla may decide to compact even if below min_threshold.")
-    , compaction_flush_all_tables_before_major_seconds(this, "compaction_flush_all_tables_before_major_seconds", value_status::Used, 86400,
-        "Set the minimum interval in seconds between flushing all tables before each major compaction (default is 86400)."
-        "This option is useful for maximizing tombstone garbage collection by releasing all active commitlog segments."
-        "Set to 0 to disable automatic flushing all tables before major compaction.")
-    /**
     * @Group Initialization properties
     * @GroupDescription The minimal properties needed for configuring a cluster.
     */
@@ -1341,7 +1322,7 @@ db::config::config(std::shared_ptr<db::extensions> exts)
     , sstable_compression_user_table_options(this, "sstable_compression_user_table_options", value_status::Used, compression_parameters{compression_parameters::algorithm::lz4_with_dicts},
         "Server-global user table compression options. If enabled, all user tables"
         "will be compressed using the provided options, unless overridden"
-        "by compression options in the table schema. The available options are:\n"
+        "by compression options in the table schema. User tables are all tables in non-system keyspaces. The available options are:\n"
         "* sstable_compression: The compression algorithm to use. Supported values: LZ4Compressor, LZ4WithDictsCompressor (default), SnappyCompressor, DeflateCompressor, ZstdCompressor, ZstdWithDictsCompressor, '' (empty string; disables compression).\n"
         "* chunk_length_in_kb: (Default: 4) The size of chunks to compress in kilobytes. Allowed values are powers of two between 1 and 128.\n"
         "* crc_check_chance: (Default: 1.0) Not implemented (option value is ignored).\n"
@@ -1394,6 +1375,10 @@ db::config::config(std::shared_ptr<db::extensions> exts)
             "Start killing reads after their collective memory consumption goes above $normal_limit * $multiplier.")
     , reader_concurrency_semaphore_cpu_concurrency(this, "reader_concurrency_semaphore_cpu_concurrency", liveness::LiveUpdate, value_status::Used, 2,
             "Admit new reads while there are less than this number of requests that need CPU.")
+    , reader_concurrency_semaphore_preemptive_abort_factor(this, "reader_concurrency_semaphore_preemptive_abort_factor", liveness::LiveUpdate, value_status::Used, 0.3,
+            "Admit new reads while their remaining time is more than this factor times their timeout times when arrived to a semaphore. Its vale means\n"
+            "* <= 0.0 means new reads will never get rejected during admission\n"
+            "* >= 1.0 means new reads will always get rejected during admission\n")
     , view_update_reader_concurrency_semaphore_serialize_limit_multiplier(this, "view_update_reader_concurrency_semaphore_serialize_limit_multiplier", liveness::LiveUpdate, value_status::Used, 2,
             "Start serializing view update reads after their collective memory consumption goes above $normal_limit * $multiplier.")
     , view_update_reader_concurrency_semaphore_kill_limit_multiplier(this, "view_update_reader_concurrency_semaphore_kill_limit_multiplier", liveness::LiveUpdate, value_status::Used, 4,
@@ -1584,7 +1569,14 @@ db::config::config(std::shared_ptr<db::extensions> exts)
     , enable_create_table_with_compact_storage(this, "enable_create_table_with_compact_storage", liveness::LiveUpdate, value_status::Used, false, "Enable the deprecated feature of CREATE TABLE WITH COMPACT STORAGE.  This feature will eventually be removed in a future version.")
     , rf_rack_valid_keyspaces(this, "rf_rack_valid_keyspaces", liveness::MustRestart, value_status::Used, false,
         "Enforce RF-rack-valid keyspaces. Additionally, if there are existing RF-rack-invalid "
-        "keyspaces, attempting to start a node with this option ON will fail.")
+        "keyspaces, attempting to start a node with this option ON will fail. "
+        "DEPRECATED. Use enforce_rack_list instead.")
+    , enforce_rack_list(this, "enforce_rack_list", liveness::MustRestart, value_status::Used, false,
+            "Enforce rack list for tablet keyspaces. "
+            "When the option is on, CREATE STATEMENT expands numeric rfs to rack lists "
+            "and ALTER STATEMENT is allowed only when rack lists are used in all DCs."
+            "Additionally, if there are existing tablet keyspaces with numeric rf in any DC "
+            "attempting to start a node with this option ON will fail.")
     // FIXME: make frequency per table in order to reduce work in each iteration.
     // Bigger tables will take longer to be resized. similar-sized tables can be batched into same iteration.
     , tablet_load_stats_refresh_interval_in_seconds(this, "tablet_load_stats_refresh_interval_in_seconds", liveness::LiveUpdate, value_status::Used, 60,
@@ -1595,6 +1587,25 @@ db::config::config(std::shared_ptr<db::extensions> exts)
         "Sets the maximum difference in percentages between the most loaded and least loaded nodes, below which the load balancer considers nodes balanced.")
     , minimal_tablet_size_for_balancing(this, "minimal_tablet_size_for_balancing", liveness::LiveUpdate, value_status::Used, service::default_target_tablet_size / 100,
         "Sets the minimal tablet size for the load balancer. For any tablet smaller than this, the balancer will use this size instead of the actual tablet size.")
+    /**
+    * @Group Ungrouped properties
+    */
+    , background_writer_scheduling_quota(this, "background_writer_scheduling_quota", value_status::Deprecated, 1.0,
+        "max cpu usage ratio (between 0 and 1) for compaction process. Not intended for setting in normal operations. Setting it to 1 or higher will disable it, recommended operational setting is 0.5.")
+    , auto_adjust_flush_quota(this, "auto_adjust_flush_quota", value_status::Deprecated, false,
+        "true: auto-adjust memtable shares for flush processes")
+    , memtable_flush_static_shares(this, "memtable_flush_static_shares", liveness::LiveUpdate, value_status::Used, 0,
+        "If set to higher than 0, ignore the controller's output and set the memtable shares statically. Do not set this unless you know what you are doing and suspect a problem in the controller. This option will be retired when the controller reaches more maturity.")
+    , compaction_static_shares(this, "compaction_static_shares", liveness::LiveUpdate, value_status::Used, 0,
+        "If set to higher than 0, ignore the controller's output and set the compaction shares statically. Do not set this unless you know what you are doing and suspect a problem in the controller. This option will be retired when the controller reaches more maturity.")
+    , compaction_max_shares(this, "compaction_max_shares", liveness::LiveUpdate, value_status::Used, default_compaction_maximum_shares,
+        "Set the maximum shares of regular compaction to the specific value. Do not set this unless you know what you are doing and suspect a problem in the controller. This option will be retired when the controller reaches more maturity.")
+    , compaction_enforce_min_threshold(this, "compaction_enforce_min_threshold", liveness::LiveUpdate, value_status::Used, false,
+        "If set to true, enforce the min_threshold option for compactions strictly. If false (default), Scylla may decide to compact even if below min_threshold.")
+    , compaction_flush_all_tables_before_major_seconds(this, "compaction_flush_all_tables_before_major_seconds", value_status::Used, 86400,
+        "Set the minimum interval in seconds between flushing all tables before each major compaction (default is 86400)."
+        "This option is useful for maximizing tombstone garbage collection by releasing all active commitlog segments."
+        "Set to 0 to disable automatic flushing all tables before major compaction.")
     , default_log_level(this, "default_log_level", value_status::Used, seastar::log_level::info, "Default log level for log messages")
     , logger_log_level(this, "logger_log_level", value_status::Used, {}, "Map of logger name to log level. Valid log levels are 'error', 'warn', 'info', 'debug' and 'trace'")
     , log_to_stdout(this, "log_to_stdout", value_status::Used, true, "Send log output to stdout")
@@ -1785,6 +1796,21 @@ const db::extensions& db::config::extensions() const {
     return *_extensions;
 }
 
+compression_parameters db::config::get_sstable_compression_user_table_options(bool dicts_feature_enabled) const {
+    if (sstable_compression_user_table_options.is_set()
+            || dicts_feature_enabled
+            || !sstable_compression_user_table_options().uses_dictionary_compressor()) {
+        return sstable_compression_user_table_options();
+    } else {
+        // Fall back to non-dict if dictionary compression is not enabled cluster-wide.
+        auto options = sstable_compression_user_table_options();
+        auto params = options.get_options();
+        auto algo = compression_parameters::non_dict_equivalent(options.get_algorithm());
+        params[compression_parameters::SSTABLE_COMPRESSION] = sstring(compression_parameters::algorithm_to_name(algo));
+        return compression_parameters{params};
+    }
+}
+
 std::map<sstring, db::experimental_features_t::feature> db::experimental_features_t::map() {
     // We decided against using the construct-on-first-use idiom here:
     // https://github.com/scylladb/scylla/pull/5369#discussion_r353614807

db/config.hh

@@ -185,13 +185,6 @@ public:
      * All values and documentation taken from
      * http://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configCassandra_yaml_r.html
      */
-    named_value<double> background_writer_scheduling_quota;
-    named_value<bool> auto_adjust_flush_quota;
-    named_value<float> memtable_flush_static_shares;
-    named_value<float> compaction_static_shares;
-    named_value<float> compaction_max_shares;
-    named_value<bool> compaction_enforce_min_threshold;
-    named_value<uint32_t> compaction_flush_all_tables_before_major_seconds;
     named_value<sstring> cluster_name;
     named_value<sstring> listen_address;
     named_value<sstring> listen_interface;
@@ -419,7 +412,13 @@ public:
     named_value<bool> enable_sstables_mc_format;
     named_value<bool> enable_sstables_md_format;
     named_value<sstring> sstable_format;
+
+    // NOTE: Do not use this option directly.
+    // Use get_sstable_compression_user_table_options() instead.
     named_value<compression_parameters> sstable_compression_user_table_options;
+
+    compression_parameters get_sstable_compression_user_table_options(bool dicts_feature_enabled) const;
+
     named_value<bool> sstable_compression_dictionaries_allow_in_ddl;
     named_value<bool> sstable_compression_dictionaries_enable_writing;
     named_value<float> sstable_compression_dictionaries_memory_budget_fraction;
@@ -440,6 +439,7 @@ public:
     named_value<uint32_t> reader_concurrency_semaphore_serialize_limit_multiplier;
     named_value<uint32_t> reader_concurrency_semaphore_kill_limit_multiplier;
     named_value<uint32_t> reader_concurrency_semaphore_cpu_concurrency;
+    named_value<float> reader_concurrency_semaphore_preemptive_abort_factor;
     named_value<uint32_t> view_update_reader_concurrency_semaphore_serialize_limit_multiplier;
     named_value<uint32_t> view_update_reader_concurrency_semaphore_kill_limit_multiplier;
     named_value<uint32_t> view_update_reader_concurrency_semaphore_cpu_concurrency;
@@ -599,12 +599,21 @@ public:
     named_value<bool> enable_create_table_with_compact_storage;
 
     named_value<bool> rf_rack_valid_keyspaces;
+    named_value<bool> enforce_rack_list;
 
     named_value<uint32_t> tablet_load_stats_refresh_interval_in_seconds;
     named_value<bool> force_capacity_based_balancing;
     named_value<float> size_based_balance_threshold_percentage;
     named_value<uint64_t> minimal_tablet_size_for_balancing;
 
+    named_value<double> background_writer_scheduling_quota;
+    named_value<bool> auto_adjust_flush_quota;
+    named_value<float> memtable_flush_static_shares;
+    named_value<float> compaction_static_shares;
+    named_value<float> compaction_max_shares;
+    named_value<bool> compaction_enforce_min_threshold;
+    named_value<uint32_t> compaction_flush_all_tables_before_major_seconds;
+
     static const sstring default_tls_priority;
 private:
     template<typename T>

db/consistency_level.cc

@@ -31,19 +31,23 @@ size_t quorum_for(const locator::effective_replication_map& erm) {
     return replication_factor ? (replication_factor / 2) + 1 : 0;
 }
 
-size_t local_quorum_for(const locator::effective_replication_map& erm, const sstring& dc) {
+static size_t get_replication_factor_for_dc(const locator::effective_replication_map& erm, const sstring& dc) {
     using namespace locator;
 
     const auto& rs = erm.get_replication_strategy();
 
     if (rs.get_type() == replication_strategy_type::network_topology) {
-        const network_topology_strategy* nrs =
+        const network_topology_strategy* nts =
             static_cast<const network_topology_strategy*>(&rs);
-        size_t replication_factor = nrs->get_replication_factor(dc);
-        return replication_factor ? (replication_factor / 2) + 1 : 0;
+        return nts->get_replication_factor(dc);
     }
 
-    return quorum_for(erm);
+    return erm.get_replication_factor();
+}
+
+size_t local_quorum_for(const locator::effective_replication_map& erm, const sstring& dc) {
+    auto rf = get_replication_factor_for_dc(erm, dc);
+    return rf ? (rf / 2) + 1 : 0;
 }
 
 size_t block_for_local_serial(const locator::effective_replication_map& erm) {
@@ -188,18 +192,30 @@ void assure_sufficient_live_nodes(
         return pending <= live ? live - pending : 0;
     };
 
+    auto make_rf_zero_error_msg = [cl] (const sstring& local_dc) {
+        return format("Cannot achieve consistency level {} in datacenter '{}' with replication factor 0. "
+                      "Ensure the keyspace is replicated to this datacenter or use a non-local consistency level.", cl, local_dc);
+    };
+
     const auto& topo = erm.get_topology();
+    const sstring& local_dc = topo.get_datacenter();
 
     switch (cl) {
     case consistency_level::ANY:
         // local hint is acceptable, and local node is always live
         break;
     case consistency_level::LOCAL_ONE:
+        if (size_t local_rf = get_replication_factor_for_dc(erm, local_dc); local_rf == 0) {
+            throw exceptions::unavailable_exception(make_rf_zero_error_msg(local_dc), cl, 1, 0);
+        }
         if (topo.count_local_endpoints(live_endpoints) < topo.count_local_endpoints(pending_endpoints) + 1) {
             throw exceptions::unavailable_exception(cl, 1, 0);
         }
         break;
     case consistency_level::LOCAL_QUORUM: {
+        if (size_t local_rf = get_replication_factor_for_dc(erm, local_dc); local_rf == 0) {
+            throw exceptions::unavailable_exception(make_rf_zero_error_msg(local_dc), cl, need, 0);
+        }
         size_t local_live = topo.count_local_endpoints(live_endpoints);
         size_t pending = topo.count_local_endpoints(pending_endpoints);
         if (local_live < need + pending) {

db/hints/internal/hint_endpoint_manager.cc

@@ -158,7 +158,7 @@ void hint_endpoint_manager::cancel_draining() noexcept {
     _sender.cancel_draining();
 }
 
-hint_endpoint_manager::hint_endpoint_manager(const endpoint_id& key, fs::path hint_directory, manager& shard_manager)
+hint_endpoint_manager::hint_endpoint_manager(const endpoint_id& key, fs::path hint_directory, manager& shard_manager, scheduling_group send_sg)
     : _key(key)
     , _shard_manager(shard_manager)
     , _store_gate("hint_endpoint_manager")
@@ -169,7 +169,7 @@ hint_endpoint_manager::hint_endpoint_manager(const endpoint_id& key, fs::path hi
     // Approximate the position of the last written hint by using the same formula as for segment id calculation in commitlog
     // TODO: Should this logic be deduplicated with what is in the commitlog?
     , _last_written_rp(this_shard_id(), std::chrono::duration_cast<std::chrono::milliseconds>(runtime::get_boot_time().time_since_epoch()).count())
-    , _sender(*this, _shard_manager.local_storage_proxy(), _shard_manager.local_db(), _shard_manager.local_gossiper())
+    , _sender(*this, _shard_manager.local_storage_proxy(), _shard_manager.local_db(), _shard_manager.local_gossiper(), send_sg)
 {}
 
 hint_endpoint_manager::hint_endpoint_manager(hint_endpoint_manager&& other)

db/hints/internal/hint_endpoint_manager.hh

@@ -63,7 +63,7 @@ private:
     hint_sender _sender;
 
 public:
-    hint_endpoint_manager(const endpoint_id& key, std::filesystem::path hint_directory, manager& shard_manager);
+    hint_endpoint_manager(const endpoint_id& key, std::filesystem::path hint_directory, manager& shard_manager, scheduling_group send_sg);
     hint_endpoint_manager(hint_endpoint_manager&&);
     ~hint_endpoint_manager();
 

db/hints/internal/hint_sender.cc

@@ -122,7 +122,7 @@ const column_mapping& hint_sender::get_column_mapping(lw_shared_ptr<send_one_fil
     return cm_it->second;
 }
 
-hint_sender::hint_sender(hint_endpoint_manager& parent, service::storage_proxy& local_storage_proxy,replica::database& local_db, const gms::gossiper& local_gossiper) noexcept
+hint_sender::hint_sender(hint_endpoint_manager& parent, service::storage_proxy& local_storage_proxy,replica::database& local_db, const gms::gossiper& local_gossiper, scheduling_group sg) noexcept
     : _stopped(make_ready_future<>())
     , _ep_key(parent.end_point_key())
     , _ep_manager(parent)
@@ -130,7 +130,7 @@ hint_sender::hint_sender(hint_endpoint_manager& parent, service::storage_proxy&
     , _resource_manager(_shard_manager._resource_manager)
     , _proxy(local_storage_proxy)
     , _db(local_db)
-    , _hints_cpu_sched_group(_db.get_streaming_scheduling_group())
+    , _hints_cpu_sched_group(sg)
     , _gossiper(local_gossiper)
     , _file_update_mutex(_ep_manager.file_update_mutex())
 {}

db/hints/internal/hint_sender.hh

@@ -120,7 +120,7 @@ private:
     std::multimap<db::replay_position, lw_shared_ptr<std::optional<promise<>>>> _replay_waiters;
 
 public:
-    hint_sender(hint_endpoint_manager& parent, service::storage_proxy& local_storage_proxy, replica::database& local_db, const gms::gossiper& local_gossiper) noexcept;
+    hint_sender(hint_endpoint_manager& parent, service::storage_proxy& local_storage_proxy, replica::database& local_db, const gms::gossiper& local_gossiper, scheduling_group sg) noexcept;
     ~hint_sender();
 
     /// \brief A constructor that should be called from the copy/move-constructor of hint_endpoint_manager.

db/hints/manager.cc

@@ -142,7 +142,7 @@ future<> directory_initializer::ensure_rebalanced() {
 }
 
 manager::manager(service::storage_proxy& proxy, sstring hints_directory, host_filter filter, int64_t max_hint_window_ms,
-        resource_manager& res_manager, sharded<replica::database>& db)
+        resource_manager& res_manager, sharded<replica::database>& db, scheduling_group sg)
     : _hints_dir(fs::path(hints_directory) / fmt::to_string(this_shard_id()))
     , _host_filter(std::move(filter))
     , _proxy(proxy)
@@ -150,6 +150,7 @@ manager::manager(service::storage_proxy& proxy, sstring hints_directory, host_fi
     , _local_db(db.local())
     , _draining_eps_gate(seastar::format("hints::manager::{}", _hints_dir.native()))
     , _resource_manager(res_manager)
+    , _hints_sending_sched_group(sg)
 {
     if (utils::get_local_injector().enter("decrease_hints_flush_period")) {
         hints_flush_period = std::chrono::seconds{1};
@@ -415,7 +416,7 @@ hint_endpoint_manager& manager::get_ep_manager(const endpoint_id& host_id, const
 
     try {
         std::filesystem::path hint_directory = hints_dir() / (_uses_host_id ? fmt::to_string(host_id) : fmt::to_string(ip));
-        auto [it, _] = _ep_managers.emplace(host_id, hint_endpoint_manager{host_id, std::move(hint_directory), *this});
+        auto [it, _] = _ep_managers.emplace(host_id, hint_endpoint_manager{host_id, std::move(hint_directory), *this, _hints_sending_sched_group});
         hint_endpoint_manager& ep_man = it->second;
 
         manager_logger.trace("Created an endpoint manager for {}", host_id);

db/hints/manager.hh

@@ -133,6 +133,7 @@ private:
 
     hint_stats _stats;
     seastar::metrics::metric_groups _metrics;
+    scheduling_group _hints_sending_sched_group;
 
     // We need to keep a variant here. Before migrating hinted handoff to using host ID, hint directories will
     // still represent IP addresses. But after the migration, they will start representing host IDs.
@@ -155,7 +156,7 @@ private:
 
 public:
     manager(service::storage_proxy& proxy, sstring hints_directory, host_filter filter,
-            int64_t max_hint_window_ms, resource_manager& res_manager, sharded<replica::database>& db);
+            int64_t max_hint_window_ms, resource_manager& res_manager, sharded<replica::database>& db, scheduling_group sg);
 
     manager(const manager&) = delete;
     manager& operator=(const manager&) = delete;

db/row_cache.cc

@@ -24,7 +24,7 @@
 #include "readers/forwardable.hh"
 #include "readers/nonforwardable.hh"
 #include "cache_mutation_reader.hh"
-#include "partition_snapshot_reader.hh"
+#include "replica/partition_snapshot_reader.hh"
 #include "keys/clustering_key_filter.hh"
 #include "utils/assert.hh"
 #include "utils/updateable_value.hh"
@@ -845,12 +845,12 @@ mutation_reader row_cache::make_nonpopulating_reader(schema_ptr schema, reader_p
             cache_entry& e = *i;
             upgrade_entry(e);
             tracing::trace(ts, "Reading partition {} from cache", pos);
-            return make_partition_snapshot_flat_reader<false, dummy_accounter>(
+            return replica::make_partition_snapshot_reader<false, dummy_accounter>(
                     schema,
                     std::move(permit),
                     e.key(),
                     query::clustering_key_filter_ranges(slice.row_ranges(*schema, e.key().key())),
-                    e.partition().read(_tracker.region(), _tracker.memtable_cleaner(), nullptr, phase_of(pos)),
+                    e.partition().read(_tracker.region(), _tracker.memtable_cleaner(), &_tracker, phase_of(pos)),
                     false,
                     _tracker.region(),
                     _read_section,

db/schema_tables.cc

@@ -96,16 +96,16 @@ static logging::logger diff_logger("schema_diff");
 /** system.schema_* tables used to store keyspace/table/type attributes prior to C* 3.0 */
 namespace db {
 namespace {
-    const auto set_use_schema_commitlog = schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
-        if (ks_name == schema_tables::NAME) {
-            props.enable_schema_commitlog();
+    const auto set_use_schema_commitlog = schema_builder::register_schema_initializer([](schema_builder& builder) {
+        if (builder.ks_name() == schema_tables::NAME) {
+            builder.enable_schema_commitlog();
         }
     });
     const auto set_group0_table_options =
-        schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
-            if (ks_name == schema_tables::NAME) {
+        schema_builder::register_schema_initializer([](schema_builder& builder) {
+            if (builder.ks_name() == schema_tables::NAME) {
                 // all schema tables are group0 tables
-                props.is_group0_table = true;
+                builder.set_is_group0_table(true);
             }
         });
 }

db/snapshot-ctl.cc

@@ -65,7 +65,7 @@ future<> snapshot_ctl::run_snapshot_modify_operation(noncopyable_function<future
     });
 }
 
-future<> snapshot_ctl::take_snapshot(sstring tag, std::vector<sstring> keyspace_names, skip_flush sf) {
+future<> snapshot_ctl::take_snapshot(sstring tag, std::vector<sstring> keyspace_names, snapshot_options opts) {
     if (tag.empty()) {
         throw std::runtime_error("You must supply a snapshot name.");
     }
@@ -74,21 +74,21 @@ future<> snapshot_ctl::take_snapshot(sstring tag, std::vector<sstring> keyspace_
         std::ranges::copy(_db.local().get_keyspaces() | std::views::keys, std::back_inserter(keyspace_names));
     };
 
-    return run_snapshot_modify_operation([tag = std::move(tag), keyspace_names = std::move(keyspace_names), sf, this] () mutable {
-        return do_take_snapshot(std::move(tag), std::move(keyspace_names), sf);
+    return run_snapshot_modify_operation([tag = std::move(tag), keyspace_names = std::move(keyspace_names), opts, this] () mutable {
+        return do_take_snapshot(std::move(tag), std::move(keyspace_names), opts);
     });
 }
 
-future<> snapshot_ctl::do_take_snapshot(sstring tag, std::vector<sstring> keyspace_names, skip_flush sf) {
+future<> snapshot_ctl::do_take_snapshot(sstring tag, std::vector<sstring> keyspace_names, snapshot_options opts) {
     co_await coroutine::parallel_for_each(keyspace_names, [tag, this] (const auto& ks_name) {
         return check_snapshot_not_exist(ks_name, tag);
     });
-    co_await coroutine::parallel_for_each(keyspace_names, [this, tag = std::move(tag), sf] (const auto& ks_name) {
-        return replica::database::snapshot_keyspace_on_all_shards(_db, ks_name, tag, bool(sf));
+    co_await coroutine::parallel_for_each(keyspace_names, [this, tag = std::move(tag), opts] (const auto& ks_name) {
+        return replica::database::snapshot_keyspace_on_all_shards(_db, ks_name, tag, opts);
     });
 }
 
-future<> snapshot_ctl::take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, skip_flush sf) {
+future<> snapshot_ctl::take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, snapshot_options opts) {
     if (ks_name.empty()) {
         throw std::runtime_error("You must supply a keyspace name");
     }
@@ -99,14 +99,14 @@ future<> snapshot_ctl::take_column_family_snapshot(sstring ks_name, std::vector<
         throw std::runtime_error("You must supply a snapshot name.");
     }
 
-    return run_snapshot_modify_operation([this, ks_name = std::move(ks_name), tables = std::move(tables), tag = std::move(tag), sf] () mutable {
-        return do_take_column_family_snapshot(std::move(ks_name), std::move(tables), std::move(tag), sf);
+    return run_snapshot_modify_operation([this, ks_name = std::move(ks_name), tables = std::move(tables), tag = std::move(tag), opts] () mutable {
+        return do_take_column_family_snapshot(std::move(ks_name), std::move(tables), std::move(tag), opts);
     });
 }
 
-future<> snapshot_ctl::do_take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, skip_flush sf) {
+future<> snapshot_ctl::do_take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, snapshot_options opts) {
     co_await check_snapshot_not_exist(ks_name, tag, tables);
-    co_await replica::database::snapshot_tables_on_all_shards(_db, ks_name, std::move(tables), std::move(tag), bool(sf));
+    co_await replica::database::snapshot_tables_on_all_shards(_db, ks_name, std::move(tables), std::move(tag), opts);
 }
 
 future<> snapshot_ctl::clear_snapshot(sstring tag, std::vector<sstring> keyspace_names, sstring cf_name) {

db/snapshot-ctl.hh

@@ -38,10 +38,14 @@ class backup_task_impl;
 
 } // snapshot namespace
 
+struct snapshot_options {
+    bool skip_flush = false;
+    gc_clock::time_point created_at = gc_clock::now();
+    std::optional<gc_clock::time_point> expires_at;
+};
+
 class snapshot_ctl : public peering_sharded_service<snapshot_ctl> {
 public:
-    using skip_flush = bool_class<class skip_flush_tag>;
-
     struct table_snapshot_details {
         int64_t total;
         int64_t live;
@@ -70,8 +74,8 @@ public:
      *
      * @param tag the tag given to the snapshot; may not be null or empty
      */
-    future<> take_snapshot(sstring tag, skip_flush sf = skip_flush::no) {
-        return take_snapshot(tag, {}, sf);
+    future<> take_snapshot(sstring tag, snapshot_options opts = {}) {
+        return take_snapshot(tag, {}, opts);
     }
 
     /**
@@ -80,7 +84,7 @@ public:
      * @param tag the tag given to the snapshot; may not be null or empty
      * @param keyspace_names the names of the keyspaces to snapshot; empty means "all"
      */
-    future<> take_snapshot(sstring tag, std::vector<sstring> keyspace_names, skip_flush sf = skip_flush::no);
+    future<> take_snapshot(sstring tag, std::vector<sstring> keyspace_names, snapshot_options opts = {});
 
     /**
      * Takes the snapshot of multiple tables. A snapshot name must be specified.
@@ -89,7 +93,7 @@ public:
      * @param tables a vector of tables names to snapshot
      * @param tag the tag given to the snapshot; may not be null or empty
      */
-    future<> take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, skip_flush sf = skip_flush::no);
+    future<> take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, snapshot_options opts = {});
 
     /**
      * Remove the snapshot with the given name from the given keyspaces.
@@ -127,8 +131,8 @@ private:
 
     friend class snapshot::backup_task_impl;
 
-    future<> do_take_snapshot(sstring tag, std::vector<sstring> keyspace_names, skip_flush sf = skip_flush::no);
-    future<> do_take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, skip_flush sf = skip_flush::no);
+    future<> do_take_snapshot(sstring tag, std::vector<sstring> keyspace_names, snapshot_options opts = {}  );
+    future<> do_take_column_family_snapshot(sstring ks_name, std::vector<sstring> tables, sstring tag, snapshot_options opts = {});
 };
 
 }

db/system_distributed_keyspace.cc

@@ -42,11 +42,11 @@ extern logging::logger cdc_log;
 
 namespace db {
 namespace {
-    const auto set_wait_for_sync_to_commitlog = schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
-        if ((ks_name == system_distributed_keyspace::NAME_EVERYWHERE && cf_name == system_distributed_keyspace::CDC_GENERATIONS_V2) ||
-            (ks_name == system_distributed_keyspace::NAME && cf_name == system_distributed_keyspace::CDC_TOPOLOGY_DESCRIPTION))
+    const auto set_wait_for_sync_to_commitlog = schema_builder::register_schema_initializer([](schema_builder& builder) {
+        if ((builder.ks_name() == system_distributed_keyspace::NAME_EVERYWHERE && builder.cf_name() == system_distributed_keyspace::CDC_GENERATIONS_V2) ||
+            (builder.ks_name() == system_distributed_keyspace::NAME && builder.cf_name() == system_distributed_keyspace::CDC_TOPOLOGY_DESCRIPTION))
         {
-            props.wait_for_sync_to_commitlog = true;
+            builder.set_wait_for_sync_to_commitlog(true);
         }
     });
 }

db/system_keyspace.cc

@@ -66,24 +66,24 @@ static thread_local auto sstableinfo_type = user_type_impl::get_instance(
 
 namespace db {
 namespace {
-    const auto set_null_sharder = schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
+    const auto set_null_sharder = schema_builder::register_schema_initializer([](schema_builder& builder) {
         // tables in the "system" keyspace which need to use null sharder
         static const std::unordered_set<sstring> tables = {
                 // empty
         };
-        if (ks_name == system_keyspace::NAME && tables.contains(cf_name)) {
-            props.use_null_sharder = true;
+        if (builder.ks_name() == system_keyspace::NAME && tables.contains(builder.cf_name())) {
+            builder.set_use_null_sharder(true);
         }
     });
-    const auto set_wait_for_sync_to_commitlog = schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
+    const auto set_wait_for_sync_to_commitlog = schema_builder::register_schema_initializer([](schema_builder& builder) {
         static const std::unordered_set<sstring> tables = {
             system_keyspace::PAXOS,
         };
-        if (ks_name == system_keyspace::NAME && tables.contains(cf_name)) {
-            props.wait_for_sync_to_commitlog = true;
+        if (builder.ks_name() == system_keyspace::NAME && tables.contains(builder.cf_name())) {
+            builder.set_wait_for_sync_to_commitlog(true);
         }
     });
-    const auto set_use_schema_commitlog = schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
+    const auto set_use_schema_commitlog = schema_builder::register_schema_initializer([](schema_builder& builder) {
         static const std::unordered_set<sstring> tables = {
             schema_tables::SCYLLA_TABLE_SCHEMA_HISTORY,
             system_keyspace::BROADCAST_KV_STORE,
@@ -108,18 +108,18 @@ namespace {
             system_keyspace::ROLE_MEMBERS,
             system_keyspace::ROLE_ATTRIBUTES,
             system_keyspace::ROLE_PERMISSIONS,
-            system_keyspace::v3::CDC_LOCAL,
+            system_keyspace::CDC_LOCAL,
             system_keyspace::DICTS,
             system_keyspace::VIEW_BUILDING_TASKS,
             system_keyspace::CLIENT_ROUTES,
         };
-        if (ks_name == system_keyspace::NAME && tables.contains(cf_name)) {
-            props.enable_schema_commitlog();
+        if (builder.ks_name() == system_keyspace::NAME && tables.contains(builder.cf_name())) {
+            builder.enable_schema_commitlog();
         }
     });
 
     const auto set_group0_table_options =
-        schema_builder::register_static_configurator([](const sstring& ks_name, const sstring& cf_name, schema_static_props& props) {
+        schema_builder::register_schema_initializer([](schema_builder& builder) {
             static const std::unordered_set<sstring> tables = {
                 // scylla_local may store a replicated tombstone related to schema
                 // (see `make_group0_schema_version_mutation`), so we include it in the group0 tables list.
@@ -142,8 +142,8 @@ namespace {
                 system_keyspace::CLIENT_ROUTES,
                 system_keyspace::REPAIR_TASKS,
             };
-            if (ks_name == system_keyspace::NAME && tables.contains(cf_name)) {
-                props.is_group0_table = true;
+            if (builder.ks_name() == system_keyspace::NAME && tables.contains(builder.cf_name())) {
+                builder.set_is_group0_table(true);
             }
         });
 }
@@ -918,7 +918,7 @@ schema_ptr system_keyspace::corrupt_data() {
     return scylla_local;
 }
 
-schema_ptr system_keyspace::v3::batches() {
+schema_ptr system_keyspace::batches() {
     static thread_local auto schema = [] {
         schema_builder builder(generate_legacy_id(NAME, BATCHES), NAME, BATCHES,
         // partition key
@@ -946,53 +946,7 @@ schema_ptr system_keyspace::v3::batches() {
     return schema;
 }
 
-schema_ptr system_keyspace::v3::built_indexes() {
-    // identical to ours, but ours otoh is a mix-in of the 3.x series cassandra one
-    return db::system_keyspace::built_indexes();
-}
-
-schema_ptr system_keyspace::v3::local() {
-    static thread_local auto schema = [] {
-        schema_builder builder(generate_legacy_id(NAME, LOCAL), NAME, LOCAL,
-        // partition key
-        {{"key", utf8_type}},
-        // clustering key
-        {},
-        // regular columns
-        {
-                {"bootstrapped", utf8_type},
-                {"broadcast_address", inet_addr_type},
-                {"cluster_name", utf8_type},
-                {"cql_version", utf8_type},
-                {"data_center", utf8_type},
-                {"gossip_generation", int32_type},
-                {"host_id", uuid_type},
-                {"listen_address", inet_addr_type},
-                {"native_protocol_version", utf8_type},
-                {"partitioner", utf8_type},
-                {"rack", utf8_type},
-                {"release_version", utf8_type},
-                {"rpc_address", inet_addr_type},
-                {"schema_version", uuid_type},
-                {"thrift_version", utf8_type},
-                {"tokens", set_type_impl::get_instance(utf8_type, true)},
-                {"truncated_at", map_type_impl::get_instance(uuid_type, bytes_type, true)},
-        },
-        // static columns
-        {},
-        // regular column name type
-        utf8_type,
-        // comment
-        "information about the local node"
-       );
-       builder.set_gc_grace_seconds(0);
-       builder.with_hash_version();
-       return builder.build(schema_builder::compact_storage::no);
-    }();
-    return schema;
-}
-
-schema_ptr system_keyspace::v3::truncated() {
+schema_ptr system_keyspace::truncated() {
     static thread_local auto local = [] {
         schema_builder builder(generate_legacy_id(NAME, TRUNCATED), NAME, TRUNCATED,
         // partition key
@@ -1022,7 +976,7 @@ schema_ptr system_keyspace::v3::truncated() {
 
 thread_local data_type replay_position_type = tuple_type_impl::get_instance({long_type, int32_type});
 
-schema_ptr system_keyspace::v3::commitlog_cleanups() {
+schema_ptr system_keyspace::commitlog_cleanups() {
     static thread_local auto local = [] {
         schema_builder builder(generate_legacy_id(NAME, COMMITLOG_CLEANUPS), NAME, COMMITLOG_CLEANUPS,
         // partition key
@@ -1049,47 +1003,7 @@ schema_ptr system_keyspace::v3::commitlog_cleanups() {
     return local;
 }
 
-schema_ptr system_keyspace::v3::peers() {
-    // identical
-    return db::system_keyspace::peers();
-}
-
-schema_ptr system_keyspace::v3::peer_events() {
-    // identical
-    return db::system_keyspace::peer_events();
-}
-
-schema_ptr system_keyspace::v3::range_xfers() {
-    // identical
-    return db::system_keyspace::range_xfers();
-}
-
-schema_ptr system_keyspace::v3::compaction_history() {
-    // identical
-    return db::system_keyspace::compaction_history();
-}
-
-schema_ptr system_keyspace::v3::sstable_activity() {
-    // identical
-    return db::system_keyspace::sstable_activity();
-}
-
-schema_ptr system_keyspace::v3::size_estimates() {
-    // identical
-    return db::system_keyspace::size_estimates();
-}
-
-schema_ptr system_keyspace::v3::large_partitions() {
-    // identical
-    return db::system_keyspace::large_partitions();
-}
-
-schema_ptr system_keyspace::v3::scylla_local() {
-    // identical
-    return db::system_keyspace::scylla_local();
-}
-
-schema_ptr system_keyspace::v3::available_ranges() {
+schema_ptr system_keyspace::available_ranges() {
     static thread_local auto schema = [] {
         schema_builder builder(generate_legacy_id(NAME, AVAILABLE_RANGES), NAME, AVAILABLE_RANGES,
         // partition key
@@ -1112,7 +1026,7 @@ schema_ptr system_keyspace::v3::available_ranges() {
     return schema;
 }
 
-schema_ptr system_keyspace::v3::views_builds_in_progress() {
+schema_ptr system_keyspace::views_builds_in_progress() {
     static thread_local auto schema = [] {
         schema_builder builder(generate_legacy_id(NAME, VIEWS_BUILDS_IN_PROGRESS), NAME, VIEWS_BUILDS_IN_PROGRESS,
         // partition key
@@ -1135,7 +1049,7 @@ schema_ptr system_keyspace::v3::views_builds_in_progress() {
     return schema;
 }
 
-schema_ptr system_keyspace::v3::built_views() {
+schema_ptr system_keyspace::built_views() {
     static thread_local auto schema = [] {
         schema_builder builder(generate_legacy_id(NAME, BUILT_VIEWS), NAME, BUILT_VIEWS,
         // partition key
@@ -1158,7 +1072,7 @@ schema_ptr system_keyspace::v3::built_views() {
     return schema;
 }
 
-schema_ptr system_keyspace::v3::scylla_views_builds_in_progress() {
+schema_ptr system_keyspace::scylla_views_builds_in_progress() {
     static thread_local auto schema = [] {
         auto id = generate_legacy_id(NAME, SCYLLA_VIEWS_BUILDS_IN_PROGRESS);
         return schema_builder(NAME, SCYLLA_VIEWS_BUILDS_IN_PROGRESS, std::make_optional(id))
@@ -1174,7 +1088,7 @@ schema_ptr system_keyspace::v3::scylla_views_builds_in_progress() {
     return schema;
 }
 
-/*static*/ schema_ptr system_keyspace::v3::cdc_local() {
+/*static*/ schema_ptr system_keyspace::cdc_local() {
     static thread_local auto cdc_local = [] {
         schema_builder builder(generate_legacy_id(NAME, CDC_LOCAL), NAME, CDC_LOCAL,
         // partition key
@@ -2180,21 +2094,21 @@ future<> system_keyspace::update_cdc_generation_id(cdc::generation_id gen_id) {
     co_await std::visit(make_visitor(
     [this] (cdc::generation_id_v1 id) -> future<> {
         co_await execute_cql(
-                format("INSERT INTO system.{} (key, streams_timestamp) VALUES (?, ?)", v3::CDC_LOCAL),
-                sstring(v3::CDC_LOCAL), id.ts);
+                format("INSERT INTO system.{} (key, streams_timestamp) VALUES (?, ?)", CDC_LOCAL),
+                sstring(CDC_LOCAL), id.ts);
     },
     [this] (cdc::generation_id_v2 id) -> future<> {
         co_await execute_cql(
-                format("INSERT INTO system.{} (key, streams_timestamp, uuid) VALUES (?, ?, ?)", v3::CDC_LOCAL),
-                sstring(v3::CDC_LOCAL), id.ts, id.id);
+                format("INSERT INTO system.{} (key, streams_timestamp, uuid) VALUES (?, ?, ?)", CDC_LOCAL),
+                sstring(CDC_LOCAL), id.ts, id.id);
     }
     ), gen_id);
 }
 
 future<std::optional<cdc::generation_id>> system_keyspace::get_cdc_generation_id() {
     auto msg = co_await execute_cql(
-            format("SELECT streams_timestamp, uuid FROM system.{} WHERE key = ?", v3::CDC_LOCAL),
-            sstring(v3::CDC_LOCAL));
+            format("SELECT streams_timestamp, uuid FROM system.{} WHERE key = ?", CDC_LOCAL),
+            sstring(CDC_LOCAL));
 
     if (msg->empty()) {
         co_return std::nullopt;
@@ -2220,19 +2134,19 @@ static const sstring CDC_REWRITTEN_KEY = "rewritten";
 future<> system_keyspace::cdc_set_rewritten(std::optional<cdc::generation_id_v1> gen_id) {
     if (gen_id) {
         return execute_cql(
-                format("INSERT INTO system.{} (key, streams_timestamp) VALUES (?, ?)", v3::CDC_LOCAL),
+                format("INSERT INTO system.{} (key, streams_timestamp) VALUES (?, ?)", CDC_LOCAL),
                 CDC_REWRITTEN_KEY, gen_id->ts).discard_result();
     } else {
         // Insert just the row marker.
         return execute_cql(
-                format("INSERT INTO system.{} (key) VALUES (?)", v3::CDC_LOCAL),
+                format("INSERT INTO system.{} (key) VALUES (?)", CDC_LOCAL),
                 CDC_REWRITTEN_KEY).discard_result();
     }
 }
 
 future<bool> system_keyspace::cdc_is_rewritten() {
     // We don't care about the actual timestamp; it's additional information for debugging purposes.
-    return execute_cql(format("SELECT key FROM system.{} WHERE key = ?", v3::CDC_LOCAL), CDC_REWRITTEN_KEY)
+    return execute_cql(format("SELECT key FROM system.{} WHERE key = ?", CDC_LOCAL), CDC_REWRITTEN_KEY)
             .then([] (::shared_ptr<cql3::untyped_result_set> msg) {
         return !msg->empty();
     });
@@ -2376,11 +2290,11 @@ std::vector<schema_ptr> system_keyspace::all_tables(const db::config& cfg) {
                     scylla_local(), db::schema_tables::scylla_table_schema_history(),
                     repair_history(),
                     repair_tasks(),
-                    v3::views_builds_in_progress(), v3::built_views(),
-                    v3::scylla_views_builds_in_progress(),
-                    v3::truncated(),
-                    v3::commitlog_cleanups(),
-                    v3::cdc_local(),
+                    views_builds_in_progress(), built_views(),
+                    scylla_views_builds_in_progress(),
+                    truncated(),
+                    commitlog_cleanups(),
+                    cdc_local(),
                     raft(), raft_snapshots(), raft_snapshot_config(), group0_history(), discovery(),
                     topology(), cdc_generations_v3(), topology_requests(), service_levels_v2(), view_build_status_v2(),
                     dicts(), view_building_tasks(), client_routes(), cdc_streams_state(), cdc_streams_history()
@@ -2403,7 +2317,7 @@ static bool maybe_write_in_user_memory(schema_ptr s) {
     return (s.get() == system_keyspace::batchlog().get())
             || (s.get() == system_keyspace::batchlog_v2().get())
             || (s.get() == system_keyspace::paxos().get())
-            || s == system_keyspace::v3::scylla_views_builds_in_progress();
+            || s == system_keyspace::scylla_views_builds_in_progress();
 }
 
 future<> system_keyspace::make(
@@ -2689,7 +2603,7 @@ mutation system_keyspace::make_size_estimates_mutation(const sstring& ks, std::v
 
 future<> system_keyspace::register_view_for_building(sstring ks_name, sstring view_name, const dht::token& token) {
     sstring req = format("INSERT INTO system.{} (keyspace_name, view_name, generation_number, cpu_id, first_token) VALUES (?, ?, ?, ?, ?)",
-            v3::SCYLLA_VIEWS_BUILDS_IN_PROGRESS);
+            SCYLLA_VIEWS_BUILDS_IN_PROGRESS);
     return execute_cql(
             std::move(req),
             std::move(ks_name),
@@ -2705,7 +2619,7 @@ future<> system_keyspace::register_view_for_building_for_all_shards(sstring ks_n
     // before all shards are registered.
     // if another shard has already registered, this won't overwrite its status. if it hasn't registered, we insert
     // a status with first_token=null and next_token=null, indicating it hasn't made progress.
-    auto&& schema = db::system_keyspace::v3::scylla_views_builds_in_progress();
+    auto&& schema = db::system_keyspace::scylla_views_builds_in_progress();
     auto timestamp = api::new_timestamp();
     mutation m{schema, partition_key::from_single_value(*schema, utf8_type->decompose(ks_name))};
 
@@ -2723,7 +2637,7 @@ future<> system_keyspace::register_view_for_building_for_all_shards(sstring ks_n
 
 future<> system_keyspace::update_view_build_progress(sstring ks_name, sstring view_name, const dht::token& token) {
     sstring req = format("INSERT INTO system.{} (keyspace_name, view_name, next_token, cpu_id) VALUES (?, ?, ?, ?)",
-            v3::SCYLLA_VIEWS_BUILDS_IN_PROGRESS);
+            SCYLLA_VIEWS_BUILDS_IN_PROGRESS);
     return execute_cql(
             std::move(req),
             std::move(ks_name),
@@ -2734,14 +2648,14 @@ future<> system_keyspace::update_view_build_progress(sstring ks_name, sstring vi
 
 future<> system_keyspace::remove_view_build_progress_across_all_shards(sstring ks_name, sstring view_name) {
     return execute_cql(
-            format("DELETE FROM system.{} WHERE keyspace_name = ? AND view_name = ?", v3::SCYLLA_VIEWS_BUILDS_IN_PROGRESS),
+            format("DELETE FROM system.{} WHERE keyspace_name = ? AND view_name = ?", SCYLLA_VIEWS_BUILDS_IN_PROGRESS),
             std::move(ks_name),
             std::move(view_name)).discard_result();
 }
 
 future<> system_keyspace::remove_view_build_progress(sstring ks_name, sstring view_name) {
     return execute_cql(
-            format("DELETE FROM system.{} WHERE keyspace_name = ? AND view_name = ? AND cpu_id = ?", v3::SCYLLA_VIEWS_BUILDS_IN_PROGRESS),
+            format("DELETE FROM system.{} WHERE keyspace_name = ? AND view_name = ? AND cpu_id = ?", SCYLLA_VIEWS_BUILDS_IN_PROGRESS),
             std::move(ks_name),
             std::move(view_name),
             int32_t(this_shard_id())).discard_result();
@@ -2749,20 +2663,20 @@ future<> system_keyspace::remove_view_build_progress(sstring ks_name, sstring vi
 
 future<> system_keyspace::mark_view_as_built(sstring ks_name, sstring view_name) {
     return execute_cql(
-            format("INSERT INTO system.{} (keyspace_name, view_name) VALUES (?, ?)", v3::BUILT_VIEWS),
+            format("INSERT INTO system.{} (keyspace_name, view_name) VALUES (?, ?)", BUILT_VIEWS),
             std::move(ks_name),
             std::move(view_name)).discard_result();
 }
 
 future<> system_keyspace::remove_built_view(sstring ks_name, sstring view_name) {
     return execute_cql(
-            format("DELETE FROM system.{} WHERE keyspace_name = ? AND view_name = ?", v3::BUILT_VIEWS),
+            format("DELETE FROM system.{} WHERE keyspace_name = ? AND view_name = ?", BUILT_VIEWS),
             std::move(ks_name),
             std::move(view_name)).discard_result();
 }
 
 future<std::vector<system_keyspace::view_name>> system_keyspace::load_built_views() {
-    return execute_cql(format("SELECT * FROM system.{}", v3::BUILT_VIEWS)).then([] (::shared_ptr<cql3::untyped_result_set> cql_result) {
+    return execute_cql(format("SELECT * FROM system.{}", BUILT_VIEWS)).then([] (::shared_ptr<cql3::untyped_result_set> cql_result) {
         return *cql_result
                 | std::views::transform([] (const cql3::untyped_result_set::row& row) {
             auto ks_name = row.get_as<sstring>("keyspace_name");
@@ -2774,7 +2688,7 @@ future<std::vector<system_keyspace::view_name>> system_keyspace::load_built_view
 
 future<std::vector<system_keyspace::view_build_progress>> system_keyspace::load_view_build_progress() {
     return execute_cql(format("SELECT keyspace_name, view_name, first_token, next_token, cpu_id FROM system.{}",
-            v3::SCYLLA_VIEWS_BUILDS_IN_PROGRESS)).then([] (::shared_ptr<cql3::untyped_result_set> cql_result) {
+            SCYLLA_VIEWS_BUILDS_IN_PROGRESS)).then([] (::shared_ptr<cql3::untyped_result_set> cql_result) {
         std::vector<view_build_progress> progress;
         for (auto& row : *cql_result) {
             auto ks_name = row.get_as<sstring>("keyspace_name");
@@ -3227,6 +3141,8 @@ future<service::topology> system_keyspace::load_topology_state(const std::unorde
         co_return ret;
     }
 
+    const bool strongly_consistent_tables = _db.features().strongly_consistent_tables;
+
     for (auto& row : *rs) {
         if (!row.has("host_id")) {
             // There are no clustering rows, only the static row.
@@ -3463,7 +3379,9 @@ future<service::topology> system_keyspace::load_topology_state(const std::unorde
             ret.session = service::session_id(some_row.get_as<utils::UUID>("session"));
         }
 
-        if (some_row.has("tablet_balancing_enabled")) {
+        if (strongly_consistent_tables) {
+            ret.tablet_balancing_enabled = false;
+        } else if (some_row.has("tablet_balancing_enabled")) {
             ret.tablet_balancing_enabled = some_row.get_as<bool>("tablet_balancing_enabled");
         } else {
             ret.tablet_balancing_enabled = true;

db/system_keyspace.hh

@@ -127,6 +127,8 @@ class system_keyspace : public seastar::peering_sharded_service<system_keyspace>
 
     static schema_ptr raft_snapshot_config();
     static schema_ptr local();
+    static schema_ptr truncated();
+    static schema_ptr commitlog_cleanups();
     static schema_ptr peers();
     static schema_ptr peer_events();
     static schema_ptr range_xfers();
@@ -137,7 +139,10 @@ class system_keyspace : public seastar::peering_sharded_service<system_keyspace>
     static schema_ptr large_rows();
     static schema_ptr large_cells();
     static schema_ptr corrupt_data();
-    static schema_ptr scylla_local();
+    static schema_ptr batches();
+    static schema_ptr available_ranges();
+    static schema_ptr built_views();
+    static schema_ptr cdc_local();
     future<> force_blocking_flush(sstring cfname);
     // This function is called when the system.peers table is read,
     // and it fixes some types of inconsistencies that can occur
@@ -204,6 +209,12 @@ public:
     static constexpr auto VIEW_BUILDING_TASKS = "view_building_tasks";
     static constexpr auto CLIENT_ROUTES = "client_routes";
     static constexpr auto VERSIONS = "versions";
+    static constexpr auto BATCHES = "batches";
+    static constexpr auto AVAILABLE_RANGES = "available_ranges";
+    static constexpr auto VIEWS_BUILDS_IN_PROGRESS = "views_builds_in_progress";
+    static constexpr auto BUILT_VIEWS = "built_views";
+    static constexpr auto SCYLLA_VIEWS_BUILDS_IN_PROGRESS = "scylla_views_builds_in_progress";
+    static constexpr auto CDC_LOCAL = "cdc_local";
 
     // auth
     static constexpr auto ROLES = "roles";
@@ -211,42 +222,6 @@ public:
     static constexpr auto ROLE_ATTRIBUTES = "role_attributes";
     static constexpr auto ROLE_PERMISSIONS = "role_permissions";
 
-    struct v3 {
-        static constexpr auto BATCHES = "batches";
-        static constexpr auto PAXOS = "paxos";
-        static constexpr auto BUILT_INDEXES = "IndexInfo";
-        static constexpr auto LOCAL = "local";
-        static constexpr auto PEERS = "peers";
-        static constexpr auto PEER_EVENTS = "peer_events";
-        static constexpr auto RANGE_XFERS = "range_xfers";
-        static constexpr auto COMPACTION_HISTORY = "compaction_history";
-        static constexpr auto SSTABLE_ACTIVITY = "sstable_activity";
-        static constexpr auto SIZE_ESTIMATES = "size_estimates";
-        static constexpr auto AVAILABLE_RANGES = "available_ranges";
-        static constexpr auto VIEWS_BUILDS_IN_PROGRESS = "views_builds_in_progress";
-        static constexpr auto BUILT_VIEWS = "built_views";
-        static constexpr auto SCYLLA_VIEWS_BUILDS_IN_PROGRESS = "scylla_views_builds_in_progress";
-        static constexpr auto CDC_LOCAL = "cdc_local";
-        static schema_ptr batches();
-        static schema_ptr built_indexes();
-        static schema_ptr local();
-        static schema_ptr truncated();
-        static schema_ptr commitlog_cleanups();
-        static schema_ptr peers();
-        static schema_ptr peer_events();
-        static schema_ptr range_xfers();
-        static schema_ptr compaction_history();
-        static schema_ptr sstable_activity();
-        static schema_ptr size_estimates();
-        static schema_ptr large_partitions();
-        static schema_ptr scylla_local();
-        static schema_ptr available_ranges();
-        static schema_ptr views_builds_in_progress();
-        static schema_ptr built_views();
-        static schema_ptr scylla_views_builds_in_progress();
-        static schema_ptr cdc_local();
-    };
-
     // Partition estimates for a given range of tokens.
     struct range_estimates {
         schema_ptr schema;
@@ -264,6 +239,7 @@ public:
     static schema_ptr batchlog_v2();
     static schema_ptr paxos();
     static schema_ptr built_indexes(); // TODO (from Cassandra): make private
+    static schema_ptr scylla_local();
     static schema_ptr raft();
     static schema_ptr raft_snapshots();
     static schema_ptr repair_history();
@@ -283,6 +259,8 @@ public:
     static schema_ptr dicts();
     static schema_ptr view_building_tasks();
     static schema_ptr client_routes();
+    static schema_ptr views_builds_in_progress();
+    static schema_ptr scylla_views_builds_in_progress();
 
     // auth
     static schema_ptr roles();

db/view/build_progress_virtual_reader.hh

@@ -195,7 +195,7 @@ public:
         return mutation_reader(std::make_unique<build_progress_reader>(
                 s,
                 std::move(permit),
-                _db.find_column_family(s->ks_name(), system_keyspace::v3::SCYLLA_VIEWS_BUILDS_IN_PROGRESS),
+                _db.find_column_family(s->ks_name(), system_keyspace::SCYLLA_VIEWS_BUILDS_IN_PROGRESS),
                 range,
                 slice,
                 std::move(trace_state),

db/view/view.cc

@@ -23,6 +23,7 @@
 
 #include <seastar/core/future-util.hh>
 #include <seastar/core/coroutine.hh>
+#include <seastar/coroutine/all.hh>
 #include <seastar/coroutine/maybe_yield.hh>
 #include <flat_map>
 
@@ -65,6 +66,7 @@
 #include "mutation/timestamp.hh"
 #include "utils/assert.hh"
 #include "utils/small_vector.hh"
+#include "view_builder.hh"
 #include "view_info.hh"
 #include "view_update_checks.hh"
 #include "types/list.hh"
@@ -2238,12 +2240,20 @@ void view_builder::setup_metrics() {
 }
 
 future<> view_builder::start_in_background(service::migration_manager& mm, utils::cross_shard_barrier barrier) {
+    auto step_fiber = make_ready_future<>();
     try {
         view_builder_init_state vbi;
         auto fail = defer([&barrier] mutable { barrier.abort(); });
-        // Guard the whole startup routine with a semaphore,
-        // so that it's not intercepted by `on_drop_view`, `on_create_view`
-        // or `on_update_view` events.
+        // Semaphore usage invariants:
+        // - One unit of _sem serializes all per-shard bookkeeping that mutates view-builder state
+        //   (_base_to_build_step, _built_views, build_status, reader resets).
+        // - The unit is held for the whole operation, including the async chain, until the state
+        //   is stable for the next operation on that shard.
+        // - Cross-shard operations acquire _sem on shard 0 for the duration of the broadcast.
+        //   Other shards acquire their own _sem only around their local handling; shard 0 skips
+        //   the local acquire because it already holds the unit from the dispatcher.
+        // Guard the whole startup routine with a semaphore so that it's not intercepted by
+        // `on_drop_view`, `on_create_view`, or `on_update_view` events.
         auto units = co_await get_units(_sem, view_builder_semaphore_units);
         // Wait for schema agreement even if we're a seed node.
         co_await mm.wait_for_schema_agreement(_db, db::timeout_clock::time_point::max(), &_as);
@@ -2264,8 +2274,10 @@ future<> view_builder::start_in_background(service::migration_manager& mm, utils
         _mnotifier.register_listener(this);
         co_await calculate_shard_build_step(vbi);
         _current_step = _base_to_build_step.begin();
-        // Waited on indirectly in stop().
-        (void)_build_step.trigger();
+
+        // If preparation above fails, run_in_background() is not invoked, just
+        // the start_in_background() emits a warning into logs and resolves
+        step_fiber = run_in_background();
     } catch (...) {
         auto ex = std::current_exception();
         auto ll = log_level::error;
@@ -2280,10 +2292,12 @@ future<> view_builder::start_in_background(service::migration_manager& mm, utils
         }
         vlogger.log(ll, "start aborted: {}", ex);
     }
+
+    co_await std::move(step_fiber);
 }
 
 future<> view_builder::start(service::migration_manager& mm, utils::cross_shard_barrier barrier) {
-    _started = start_in_background(mm, std::move(barrier));
+    _step_fiber = start_in_background(mm, std::move(barrier));
     return make_ready_future<>();
 }
 
@@ -2293,12 +2307,12 @@ future<> view_builder::drain() {
     }
     vlogger.info("Draining view builder");
     _as.request_abort();
-    co_await std::move(_started);
     co_await _mnotifier.unregister_listener(this);
     co_await _vug.drain();
     co_await _sem.wait();
     _sem.broken();
-    co_await _build_step.join();
+    _build_step.broken();
+    co_await std::move(_step_fiber);
     co_await coroutine::parallel_for_each(_base_to_build_step, [] (std::pair<const table_id, build_step>& p) {
         return p.second.reader.close();
     });
@@ -2667,63 +2681,59 @@ static bool should_ignore_tablet_keyspace(const replica::database& db, const sst
     return db.features().view_building_coordinator && db.has_keyspace(ks_name) && db.find_keyspace(ks_name).uses_tablets();
 }
 
-future<> view_builder::dispatch_create_view(sstring ks_name, sstring view_name) {
-    if (should_ignore_tablet_keyspace(_db, ks_name)) {
-        return make_ready_future<>();
-    }
-    return with_semaphore(_sem, view_builder_semaphore_units, [this, ks_name = std::move(ks_name), view_name = std::move(view_name)] () mutable {
-        // This runs on shard 0 only; seed the global rows before broadcasting.
-        return handle_seed_view_build_progress(ks_name, view_name).then([this, ks_name = std::move(ks_name), view_name = std::move(view_name)] () mutable {
-            return container().invoke_on_all([ks_name = std::move(ks_name), view_name = std::move(view_name)] (view_builder& vb) mutable {
-                return vb.handle_create_view_local(std::move(ks_name), std::move(view_name));
-            });
-        });
-    });
+future<view_builder::view_builder_units> view_builder::get_or_adopt_view_builder_lock(view_builder_units_opt units) {
+    co_return units ? std::move(*units) : co_await get_units(_sem, view_builder_semaphore_units);
 }
 
-future<> view_builder::handle_seed_view_build_progress(sstring ks_name, sstring view_name) {
+future<> view_builder::dispatch_create_view(sstring ks_name, sstring view_name) {
+    if (should_ignore_tablet_keyspace(_db, ks_name)) {
+        co_return;
+    }
+
+    auto units = co_await get_or_adopt_view_builder_lock(std::nullopt);
+    co_await handle_seed_view_build_progress(ks_name, view_name);
+
+    co_await coroutine::all(
+        [this, ks_name, view_name, units = std::move(units)] mutable -> future<> {
+            co_await handle_create_view_local(ks_name, view_name, std::move(units)); },
+        [this, ks_name, view_name] mutable -> future<> {
+            co_await container().invoke_on_others([ks_name = std::move(ks_name), view_name = std::move(view_name)] (view_builder& vb) mutable -> future<> {
+                return vb.handle_create_view_local(ks_name, view_name, std::nullopt); }); });
+}
+
+future<> view_builder::handle_seed_view_build_progress(const sstring& ks_name, const sstring& view_name) {
     auto view = view_ptr(_db.find_schema(ks_name, view_name));
     auto& step = get_or_create_build_step(view->view_info()->base_id());
     return _sys_ks.register_view_for_building_for_all_shards(view->ks_name(), view->cf_name(), step.current_token());
 }
 
-future<> view_builder::handle_create_view_local(sstring ks_name, sstring view_name){
-    if (this_shard_id() == 0) { 
-        return handle_create_view_local_impl(std::move(ks_name), std::move(view_name));
-    } else {
-        return with_semaphore(_sem, view_builder_semaphore_units, [this, ks_name = std::move(ks_name), view_name = std::move(view_name)] () mutable {
-            return handle_create_view_local_impl(std::move(ks_name), std::move(view_name));
-        });
-    }
-}
-
-future<> view_builder::handle_create_view_local_impl(sstring ks_name, sstring view_name) {
+future<> view_builder::handle_create_view_local(const sstring& ks_name, const sstring& view_name, view_builder_units_opt units) {
+    [[maybe_unused]] auto sem_units = co_await get_or_adopt_view_builder_lock(std::move(units));
     auto view = view_ptr(_db.find_schema(ks_name, view_name));
     auto& step = get_or_create_build_step(view->view_info()->base_id());
-    return when_all(step.base->await_pending_writes(), step.base->await_pending_streams()).discard_result().then([this, &step] {
-        return flush_base(step.base, _as);
-    }).then([this, view, &step] () {
+    try {
+        co_await coroutine::all(
+            [&step] -> future<> {
+                co_await step.base->await_pending_writes(); },
+            [&step] -> future<> {
+                co_await step.base->await_pending_streams(); });
+        co_await flush_base(step.base, _as);
+    
         // This resets the build step to the current token. It may result in views currently
         // being built to receive duplicate updates, but it simplifies things as we don't have
         // to keep around a list of new views to build the next time the reader crosses a token
         // threshold.
-        return initialize_reader_at_current_token(step).then([this, view, &step] () mutable {
-            return add_new_view(view, step);
-        }).then_wrapped([this, view] (future<>&& f) {
-            try {
-                f.get();
-            } catch (abort_requested_exception&) {
-                vlogger.debug("Aborted while setting up view for building {}.{}", view->ks_name(), view->cf_name());
-            } catch (raft::request_aborted&) {
-                vlogger.debug("Aborted while setting up view for building {}.{}", view->ks_name(), view->cf_name());
-            } catch (...) {
-                vlogger.error("Error setting up view for building {}.{}: {}", view->ks_name(), view->cf_name(), std::current_exception());
-            }
+        co_await initialize_reader_at_current_token(step);
+        co_await add_new_view(view, step);
+    } catch (abort_requested_exception&) {
+        vlogger.debug("Aborted while setting up view for building {}.{}", view->ks_name(), view->cf_name());
+    } catch (raft::request_aborted&) {
+        vlogger.debug("Aborted while setting up view for building {}.{}", view->ks_name(), view->cf_name());
+    } catch (...) {
+        vlogger.error("Error setting up view for building {}.{}: {}", view->ks_name(), view->cf_name(), std::current_exception());
+    }
 
-            // Waited on indirectly in stop().
-            static_cast<void>(_build_step.trigger());
-        });
-    });
+    _build_step.signal();
 }
 
 void view_builder::on_create_view(const sstring& ks_name, const sstring& view_name) {
@@ -2760,62 +2770,55 @@ void view_builder::on_update_view(const sstring& ks_name, const sstring& view_na
 
 future<> view_builder::dispatch_drop_view(sstring ks_name, sstring view_name) {
     if (should_ignore_tablet_keyspace(_db, ks_name)) {
-        return make_ready_future<>();
+        co_return;
     }
 
-    return with_semaphore(_sem, view_builder_semaphore_units, [this, ks_name = std::move(ks_name), view_name = std::move(view_name)] () mutable {
-        // This runs on shard 0 only; broadcast local cleanup before global cleanup.
-        return container().invoke_on_all([ks_name, view_name] (view_builder& vb) mutable {
-            return vb.handle_drop_view_local(std::move(ks_name), std::move(view_name));
-        }).then([this, ks_name = std::move(ks_name), view_name = std::move(view_name)] () mutable {
-            return handle_drop_view_global_cleanup(std::move(ks_name), std::move(view_name));
-        });
-    });
+    auto units = co_await get_or_adopt_view_builder_lock(std::nullopt);
+
+    co_await coroutine::all(
+        [this, ks_name, view_name, units = std::move(units)] mutable -> future<> {
+            co_await handle_drop_view_local(ks_name, view_name, std::move(units)); },
+        [this, ks_name, view_name] mutable -> future<> {
+            co_await container().invoke_on_others([ks_name = std::move(ks_name), view_name = std::move(view_name)] (view_builder& vb) mutable -> future<> {
+                return vb.handle_drop_view_local(ks_name, view_name, std::nullopt); });});
+    co_await handle_drop_view_global_cleanup(ks_name, view_name);
 }
 
-future<> view_builder::handle_drop_view_local(sstring ks_name, sstring view_name) {
-    if (this_shard_id() == 0) { 
-        return handle_drop_view_local_impl(std::move(ks_name), std::move(view_name));
-    } else {
-        return with_semaphore(_sem, view_builder_semaphore_units, [this, ks_name = std::move(ks_name), view_name = std::move(view_name)] () mutable {
-            return handle_drop_view_local_impl(std::move(ks_name), std::move(view_name));
-        });
-    }
-}
-
-future<> view_builder::handle_drop_view_local_impl(sstring ks_name, sstring view_name) {
+future<> view_builder::handle_drop_view_local(const sstring& ks_name, const sstring& view_name, view_builder_units_opt units) {
+    [[maybe_unused]] auto sem_units = co_await get_or_adopt_view_builder_lock(std::move(units));
     vlogger.info0("Stopping to build view {}.{}", ks_name, view_name);
-    // The view is absent from the database at this point, so find it by brute force.
-    ([&, this] {
-        for (auto& [_, step] : _base_to_build_step) {
-            if (step.build_status.empty() || step.build_status.front().view->ks_name() != ks_name) {
-                continue;
-            }
-            for (auto it = step.build_status.begin(); it != step.build_status.end(); ++it) {
-                if (it->view->cf_name() == view_name) {
-                    _built_views.erase(it->view->id());
-                    step.build_status.erase(it);
-                    return;
-                }
+
+    for (auto& [_, step] : _base_to_build_step) {
+        if (step.build_status.empty() || step.build_status.front().view->ks_name() != ks_name) {
+            continue;
+        }
+        for (auto it = step.build_status.begin(); it != step.build_status.end(); ++it) {
+            if (it->view->cf_name() == view_name) {
+                _built_views.erase(it->view->id());
+                step.build_status.erase(it);
+                co_return;
             }
         }
-    })();
-    return make_ready_future<>();  
+    }
 }
 
-future<> view_builder::handle_drop_view_global_cleanup(sstring ks_name, sstring view_name) {
+future<> view_builder::handle_drop_view_global_cleanup(const sstring& ks_name, const sstring& view_name) {
     if (this_shard_id() != 0) {
-        return make_ready_future<>();
+        co_return;
     }
     vlogger.info0("Starting view global cleanup {}.{}", ks_name, view_name);
-    return when_all_succeed(
-                _sys_ks.remove_view_build_progress_across_all_shards(ks_name, view_name),
-                _sys_ks.remove_built_view(ks_name, view_name),
-                remove_view_build_status(ks_name, view_name))
-                    .discard_result()
-                    .handle_exception([ks_name, view_name] (std::exception_ptr ep) {
-        vlogger.warn("Failed to cleanup view {}.{}: {}", ks_name, view_name, ep);
-    });
+    
+    try {
+        co_await coroutine::all(
+            [this, &ks_name, &view_name] -> future<>  {
+                co_await _sys_ks.remove_view_build_progress_across_all_shards(ks_name, view_name); },
+            [this, &ks_name, &view_name] -> future<>  {
+                co_await _sys_ks.remove_built_view(ks_name, view_name); },
+            [this, &ks_name, &view_name] -> future<>  {
+                co_await remove_view_build_status(ks_name, view_name); });
+    } catch (...) {
+        vlogger.warn("Failed to cleanup view {}.{}: {}", ks_name, view_name, std::current_exception());
+    }
 }
 
 void view_builder::on_drop_view(const sstring& ks_name, const sstring& view_name) {
@@ -2829,14 +2832,15 @@ void view_builder::on_drop_view(const sstring& ks_name, const sstring& view_name
     }));
 }
 
-future<> view_builder::do_build_step() {
-    // Run the view building in the streaming scheduling group
-    // so that it doesn't impact other tasks with higher priority.
-    seastar::thread_attributes attr;
-    attr.sched_group = _db.get_streaming_scheduling_group();
-    return seastar::async(std::move(attr), [this] {
+future<> view_builder::run_in_background() {
+    return seastar::async([this] {
         exponential_backoff_retry r(1s, 1min);
-        while (!_base_to_build_step.empty() && !_as.abort_requested()) {
+        while (!_as.abort_requested()) {
+            try {
+                _build_step.wait([this] { return !_base_to_build_step.empty(); }).get();
+            } catch (const seastar::broken_condition_variable&) {
+                return;
+            }
             auto units = get_units(_sem, view_builder_semaphore_units).get();
             ++_stats.steps_performed;
             try {
@@ -3707,7 +3711,7 @@ void validate_view_keyspace(const data_dictionary::database& db, std::string_vie
 
     try {
         locator::assert_rf_rack_valid_keyspace(keyspace_name, tmptr, rs);
-    } catch (const std::exception& e) {
+    } catch (const std::invalid_argument& e) {
         throw std::logic_error(fmt::format(
             "Materialized views and secondary indexes are not supported on the keyspace '{}': {}",
             keyspace_name, e.what()));

db/view/view_builder.hh

@@ -11,13 +11,13 @@
 #include "query/query-request.hh"
 #include "service/migration_listener.hh"
 #include "service/raft/raft_group0_client.hh"
-#include "utils/serialized_action.hh"
 #include "utils/cross-shard-barrier.hh"
 #include "replica/database.hh"
 
 #include <seastar/core/abort_source.hh>
 #include <seastar/core/future.hh>
 #include <seastar/core/semaphore.hh>
+#include <seastar/core/condition-variable.hh>
 #include <seastar/core/sharded.hh>
 #include <seastar/core/shared_future.hh>
 #include <seastar/core/shared_ptr.hh>
@@ -104,6 +104,12 @@ class view_update_generator;
  *            redo the missing step, for simplicity.
  */
 class view_builder final : public service::migration_listener::only_view_notifications, public seastar::peering_sharded_service<view_builder> {
+    //aliasing for semaphore units that will be used throughout the class
+    using view_builder_units = semaphore_units<named_semaphore_exception_factory>;
+
+    //aliasing for optional semaphore units that will be used throughout the class
+    using view_builder_units_opt = std::optional<view_builder_units>;
+
     /**
      * Keeps track of the build progress for a particular view.
      * When the view is built, next_token == first_token.
@@ -168,14 +174,24 @@ class view_builder final : public service::migration_listener::only_view_notific
     reader_permit _permit;
     base_to_build_step_type _base_to_build_step;
     base_to_build_step_type::iterator _current_step = _base_to_build_step.end();
-    serialized_action _build_step{std::bind(&view_builder::do_build_step, this)};
+    condition_variable _build_step;
     static constexpr size_t view_builder_semaphore_units = 1;
     // Ensures bookkeeping operations are serialized, meaning that while we execute
     // a build step we don't consider newly added or removed views. This simplifies
     // the algorithms. Also synchronizes an operation wrt. a call to stop().
+    // Semaphore usage invariants:
+    // - One unit of _sem serializes all per-shard bookkeeping that mutates view-builder state
+    //   (_base_to_build_step, _built_views, build_status, reader resets).
+    // - The unit is held for the whole operation, including the async chain, until the state
+    //   is stable for the next operation on that shard.
+    // - Cross-shard operations acquire _sem on shard 0 for the duration of the broadcast.
+    //   Other shards acquire their own _sem only around their local handling; shard 0 skips
+    //   the local acquire because it already holds the unit from the dispatcher.
+    // Guard the whole startup routine with a semaphore so that it's not intercepted by
+    // `on_drop_view`, `on_create_view`, or `on_update_view` events.
     seastar::named_semaphore _sem{view_builder_semaphore_units, named_semaphore_exception_factory{"view builder"}};
     seastar::abort_source _as;
-    future<> _started = make_ready_future<>();
+    future<> _step_fiber = make_ready_future<>();
     // Used to coordinate between shards the conclusion of the build process for a particular view.
     std::unordered_set<table_id> _built_views;
     // Used for testing.
@@ -262,19 +278,18 @@ private:
     void setup_shard_build_step(view_builder_init_state& vbi, std::vector<system_keyspace_view_name>, std::vector<system_keyspace_view_build_progress>);
     future<> calculate_shard_build_step(view_builder_init_state& vbi);
     future<> add_new_view(view_ptr, build_step&);
-    future<> do_build_step();
+    future<> run_in_background();
     void execute(build_step&, exponential_backoff_retry);
     future<> maybe_mark_view_as_built(view_ptr, dht::token);
     future<> mark_as_built(view_ptr);
     void setup_metrics();
     future<> dispatch_create_view(sstring ks_name, sstring view_name);
     future<> dispatch_drop_view(sstring ks_name, sstring view_name);
-    future<> handle_seed_view_build_progress(sstring ks_name, sstring view_name);
-    future<> handle_create_view_local(sstring ks_name, sstring view_name);
-    future<> handle_drop_view_local(sstring ks_name, sstring view_name);
-    future<> handle_create_view_local_impl(sstring ks_name, sstring view_name);
-    future<> handle_drop_view_local_impl(sstring ks_name, sstring view_name);
-    future<> handle_drop_view_global_cleanup(sstring ks_name, sstring view_name);
+    future<> handle_seed_view_build_progress(const sstring& ks_name, const sstring& view_name);
+    future<> handle_create_view_local(const sstring& ks_name, const sstring& view_name, view_builder_units_opt units);
+    future<> handle_drop_view_local(const sstring& ks_name, const sstring& view_name, view_builder_units_opt units);
+    future<> handle_drop_view_global_cleanup(const sstring& ks_name, const sstring& view_name);
+    future<view_builder_units> get_or_adopt_view_builder_lock(view_builder_units_opt units);
 
     template <typename Func1, typename Func2>
     future<> write_view_build_status(Func1&& fn_group0, Func2&& fn_sys_dist) {

db/view/view_building_worker.cc

@@ -242,7 +242,7 @@ future<> view_building_worker::create_staging_sstable_tasks() {
                 utils::UUID_gen::get_time_UUID(), view_building_task::task_type::process_staging, false,
                 table_id, ::table_id{}, {my_host_id, sst_info.shard}, sst_info.last_token
             };
-            auto mut = co_await _group0.client().sys_ks().make_view_building_task_mutation(guard.write_timestamp(), task);
+            auto mut = co_await _sys_ks.make_view_building_task_mutation(guard.write_timestamp(), task);
             cmuts.emplace_back(std::move(mut));
         }
     }
@@ -386,7 +386,6 @@ future<> view_building_worker::update_built_views() {
         auto schema = _db.find_schema(table_id);
         return std::make_pair(schema->ks_name(), schema->cf_name());
     };
-    auto& sys_ks = _group0.client().sys_ks();
 
     std::set<std::pair<sstring, sstring>> built_views;
     for (auto& [id, statuses]: _vb_state_machine.views_state.status_map) {
@@ -395,22 +394,22 @@ future<> view_building_worker::update_built_views() {
         }
     }
 
-    auto local_built = co_await sys_ks.load_built_views() | std::views::filter([&] (auto& v) {
+    auto local_built = co_await _sys_ks.load_built_views() | std::views::filter([&] (auto& v) {
         return !_db.has_keyspace(v.first) || _db.find_keyspace(v.first).uses_tablets();
     }) | std::ranges::to<std::set>();
 
     // Remove dead entries
     for (auto& view: local_built) {
         if (!built_views.contains(view)) {
-            co_await sys_ks.remove_built_view(view.first, view.second);
+            co_await _sys_ks.remove_built_view(view.first, view.second);
         }
     }
 
     // Add new entries
     for (auto& view: built_views) {
         if (!local_built.contains(view)) {
-            co_await sys_ks.mark_view_as_built(view.first, view.second);
-            co_await sys_ks.remove_view_build_progress_across_all_shards(view.first, view.second);
+            co_await _sys_ks.mark_view_as_built(view.first, view.second);
+            co_await _sys_ks.remove_view_build_progress_across_all_shards(view.first, view.second);
         }
     }
 }

db/virtual_tables.cc

@@ -68,6 +68,8 @@ public:
             .with_column("peer", inet_addr_type, column_kind::partition_key)
             .with_column("dc", utf8_type)
             .with_column("up", boolean_type)
+            .with_column("draining", boolean_type)
+            .with_column("excluded", boolean_type)
             .with_column("status", utf8_type)
             .with_column("load", utf8_type)
             .with_column("tokens", int32_type)
@@ -107,8 +109,11 @@ public:
 
                 if (tm.get_topology().has_node(hostid)) {
                     // Not all entries in gossiper are present in the topology
-                    sstring dc = tm.get_topology().get_location(hostid).dc;
+                    auto& node = tm.get_topology().get_node(hostid);
+                    sstring dc = node.dc_rack().dc;
                     set_cell(cr, "dc", dc);
+                    set_cell(cr, "draining", node.is_draining());
+                    set_cell(cr, "excluded", node.is_excluded());
                 }
 
                 if (ownership.contains(eps.get_ip())) {
@@ -1134,6 +1139,8 @@ public:
             set_cell(r.cells(), "dc", node.dc());
             set_cell(r.cells(), "rack", node.rack());
             set_cell(r.cells(), "up", _gossiper.local().is_alive(host));
+            set_cell(r.cells(), "draining", node.is_draining());
+            set_cell(r.cells(), "excluded", node.is_excluded());
             if (auto ip = _gossiper.local().get_address_map().find(host)) {
                 set_cell(r.cells(), "ip", data_value(inet_address(*ip)));
             }
@@ -1144,6 +1151,9 @@ public:
             if (stats && stats->capacity.contains(host)) {
                 auto capacity = stats->capacity.at(host);
                 set_cell(r.cells(), "storage_capacity", data_value(int64_t(capacity)));
+                if (auto ts_iter = stats->tablet_stats.find(host); ts_iter != stats->tablet_stats.end()) {
+                    set_cell(r.cells(), "effective_capacity", data_value(int64_t(ts_iter->second.effective_capacity)));
+                }
 
                 if (auto utilization = load.get_allocated_utilization(host)) {
                     set_cell(r.cells(), "storage_allocated_utilization", data_value(double(*utilization)));
@@ -1168,9 +1178,12 @@ private:
             .with_column("rack", utf8_type)
             .with_column("ip", inet_addr_type)
             .with_column("up", boolean_type)
+            .with_column("draining", boolean_type)
+            .with_column("excluded", boolean_type)
             .with_column("tablets_allocated", long_type)
             .with_column("tablets_allocated_per_shard", double_type)
             .with_column("storage_capacity", long_type)
+            .with_column("effective_capacity", long_type)
             .with_column("storage_allocated_load", long_type)
             .with_column("storage_allocated_utilization", double_type)
             .with_column("storage_load", long_type)
@@ -1484,7 +1497,7 @@ future<> initialize_virtual_tables(
     co_await add_table(std::make_unique<cdc_streams_table>(db, ss));
 
     db.find_column_family(system_keyspace::size_estimates()).set_virtual_reader(mutation_source(db::size_estimates::virtual_reader(db, sys_ks.local())));
-    db.find_column_family(system_keyspace::v3::views_builds_in_progress()).set_virtual_reader(mutation_source(db::view::build_progress_virtual_reader(db)));
+    db.find_column_family(system_keyspace::views_builds_in_progress()).set_virtual_reader(mutation_source(db::view::build_progress_virtual_reader(db)));
     db.find_column_family(system_keyspace::built_indexes()).set_virtual_reader(mutation_source(db::index::built_indexes_virtual_reader(db)));
 }
 

debug.cc

@@ -11,5 +11,6 @@
 namespace debug {
 
 seastar::sharded<replica::database>* volatile the_database = nullptr;
+seastar::scheduling_group streaming_scheduling_group;
 
 }

debug.hh

@@ -17,7 +17,7 @@ class database;
 namespace debug {
 
 extern seastar::sharded<replica::database>* volatile the_database;
-
+extern seastar::scheduling_group streaming_scheduling_group;
 
 }
 

dist/common/scripts/scylla_coredump_setup

@@ -114,6 +114,10 @@ WantedBy=local-fs.target scylla-server.service
 '''[1:-1]
             with open('/etc/systemd/system/var-lib-systemd-coredump.mount', 'w') as f:
                 f.write(dot_mount)
+            # in case we have old mounts in deleted state hanging around from older installation
+            # systemd doesn't seem to be able to deal with those properly, and assume they are still active
+            # and doesn't do anything about them
+            run('umount  /var/lib/systemd/coredump', shell=True, check=False)
             os.makedirs('/var/lib/scylla/coredump', exist_ok=True)
             systemd_unit.reload()
             systemd_unit('var-lib-systemd-coredump.mount').enable()

docs/_utils/redirects.yaml

@@ -1,6 +1,14 @@
 ### a dictionary of redirections
 #old path: new path
 
+# Remove an outdated KB
+
+/stable/kb/perftune-modes-sync.html: /stable/kb/index.html
+
+# Remove the troubleshooting page relevant for Open Source only
+
+/stable/troubleshooting/missing-dotmount-files.html: /troubleshooting/index.html
+
 # Move the diver information to another project
 
 /stable/using-scylla/drivers/index.html: https://docs.scylladb.com/stable/drivers/index.html

docs/cql/ddl.rst

@@ -190,7 +190,7 @@ then every rack in every datacenter receives a replica, except for racks compris
 of only :doc:`zero-token nodes </architecture/zero-token-nodes>`. Racks added after
 the keyspace creation do not receive replicas.
 
-When ``rf_rack_valid_keyspaces``` is enabled in the config and the keyspace is tablet-based,
+When ``enforce_rack_list`` (or (deprecated) ``rf_rack_valid_keyspaces``) is enabled in the config and the keyspace is tablet-based,
 the numeric replication factor is automatically expanded into a rack list when the statement is
 executed, which can be observed in the DESCRIBE output afterwards. If the numeric RF is smaller than
 the number of racks in a DC, a subset of racks is chosen arbitrarily.
@@ -1026,7 +1026,29 @@ You can enable the after-repair tombstone GC by setting the ``repair`` mode usin
 
     ALTER TABLE ks.cf WITH tombstone_gc = {'mode':'repair'} ;
 
-The following modes are available:
+To support writes arriving out-of-order -- either due to natural delays, or user provided timestamps -- the repair mode has a propagation delay.
+Out-of-order writes present a problem for repair mode tombstone gc. Consider the following example sequence of events:
+
+1) Write ``DELETE FROM table WHERE key = K1`` arrives at the node.
+2) Repair is run.
+3) Compaction runs and garbage collects the tombstone for ``key = K1``.
+4) Write ``INSERT INTO table (key, ...) VALUES (K1, ...)`` arrives at the node with timestamp smaller than that of the delete. The tombstone for ``key = K1`` should apply to this write, but it is already garbage collected, so this data is resurrected.
+
+Propagation delay solves this problem by establishing a window before repair, where tombstones are not yet garbage collectible: a tombstone is garbage collectible if it was written before the last repair by at least the propagation delay.
+
+The value of the propagation delay can be set via the ``propagation_delay_in_seconds`` parameter:
+
+.. code-block:: cql
+
+    CREATE TABLE ks.cf (key blob PRIMARY KEY, val blob) WITH tombstone_gc = {'mode':'repair', 'propagation_delay_in_seconds': 120};
+
+.. code-block:: cql
+
+    ALTER TABLE ks.cf WITH tombstone_gc = {'mode':'repair', 'propagation_delay_in_seconds': 120};
+
+The default value of the propagation delay is 1 hour. This parameter should only be changed if your application uses user provided timestamps and writes and deletes can arrive out-of-order by more than the default 1 hour.
+
+The following tombstone gc modes are available:
 
 .. list-table::
    :widths: 20 80

docs/cql/dml/select.rst

@@ -241,8 +241,8 @@ Currently, the possible orderings are limited by the :ref:`clustering order <clu
 
 .. _vector-queries:
 
-Vector queries
-~~~~~~~~~~~~~~
+Vector queries :label-note:`ScyllaDB Cloud`
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 The ``ORDER BY`` clause can also be used with vector columns to perform the approximate nearest neighbor (ANN) search. 
 When using vector columns, the syntax is as follows:
@@ -280,11 +280,25 @@ For example::
       FROM ImageEmbeddings
       ORDER BY embedding ANN OF [0.1, 0.2, 0.3, 0.4] LIMIT 5;
 
-.. warning:: 
 
-  Currently, vector queries do not support filtering with ``WHERE`` clause,
-  grouping with ``GROUP BY`` and paging. This will be added in the future releases.
+Vector queries also support filtering with ``WHERE`` clauses on columns that are part of the primary key.
 
+For example::
+
+    SELECT image_id FROM ImageEmbeddings
+      WHERE user_id = 'user123'
+      ORDER BY embedding ANN OF [0.1, 0.2, 0.3, 0.4] LIMIT 5;
+
+The supported operations are equal relations (``=`` and ``IN``) with restrictions as in regular ``WHERE`` clauses. See :ref:`WHERE <where-clause>`.
+
+Other filtering scenarios are currently not supported.
+
+.. note::
+
+   Vector indexes are supported in ScyllaDB Cloud only in clusters that have the Vector Search feature enabled.
+   Vector indexes do not support all ScyllaDB features (e.g., tracing, TTL, paging, and grouping). More information
+   about Vector Search is available in the
+   `ScyllaDB Cloud documentation <https://cloud.docs.scylladb.com/stable/vector-search/>`_.
 
 .. _limit-clause:
 

docs/cql/secondary-indexes.rst

@@ -129,17 +129,15 @@ More on :doc:`Local Secondary Indexes </features/local-secondary-indexes>`
 
 .. _create-vector-index-statement:
 
-Vector Index :label-caution:`Experimental` :label-note:`ScyllaDB Cloud`
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Vector Index :label-note:`ScyllaDB Cloud`
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 .. note::
 
-   Vector indexes are supported in ScyllaDB Cloud only in the clusters that have the vector search feature enabled.
-   Moreover, vector indexes are an experimental feature that:
-   
-     * is not suitable for production use,
-     * does not guarantee backward compatibility between ScyllaDB versions,
-     * does not support all the features of ScyllaDB (e.g., tracing, filtering, TTL).
+   Vector indexes are supported in ScyllaDB Cloud only in clusters that have the Vector Search feature enabled.
+   Vector indexes do not support all ScyllaDB features (e.g., tracing, TTL, paging, and grouping). More information
+   about Vector Search is available in the
+   `ScyllaDB Cloud documentation <https://cloud.docs.scylladb.com/stable/vector-search/>`_.
 
 ScyllaDB supports creating vector indexes on tables, allowing queries on the table to use those indexes for efficient
 similarity search on vector data. 
@@ -177,6 +175,26 @@ The following options are supported for vector indexes. All of them are optional
 |                              | as ``efSearch``. Higher values lead to better recall (i.e., more relevant results are found)             |               |
 |                              | but increase query latency. Supported values are integers between 1 and 4096.                            |               |
 +------------------------------+----------------------------------------------------------------------------------------------------------+---------------+
+| ``quantization``             | The quantization method to use for compressing vectors in Vector Index. Vectors in base table            | ``f32``       |
+|                              | are never compressed. Supported values (case-insensitive) are:                                           |               |
+|                              |                                                                                                          |               |
+|                              | * ``f32``: 32-bit single-precision IEEE 754 floating-point.                                              |               |
+|                              | * ``f16``: 16-bit standard half-precision floating-point (IEEE 754).                                     |               |
+|                              | * ``bf16``: 16-bit "Brain" floating-point (optimized for ML workloads).                                  |               |
+|                              | * ``i8``: 8-bit signed integer.                                                                          |               |
+|                              | * ``b1``: 1-bit binary value (packed 8 per byte).                                                        |               |
++------------------------------+----------------------------------------------------------------------------------------------------------+---------------+
+| ``oversampling``             | A multiplier for the candidate set size during the search phase. For example, if a query asks for 10     | ``1.0``       |
+|                              | similar vectors (``LIMIT 10``) and ``oversampling`` is 2.0, the search will initially retrieve 20        |               |
+|                              | candidates. This can improve accuracy at the cost of latency. Supported values are                       |               |
+|                              | floating-point numbers between 1.0 (no oversampling) and 100.0.                                          |               |
++------------------------------+----------------------------------------------------------------------------------------------------------+---------------+
+| ``rescoring``                | Flag enabling recalculation of similarity scores with full precision and re-ranking of the candidate set.| ``false``     |
+|                              | Valid only for quantization below ``f32``. Supported values are:                                         |               |
+|                              |                                                                                                          |               |
+|                              | * ``true``: Enable rescoring.                                                                            |               |
+|                              | * ``false``: Disable rescoring.                                                                          |               |
++------------------------------+----------------------------------------------------------------------------------------------------------+---------------+
 
 
 .. _drop-index-statement:

docs/cql/types.rst

@@ -665,6 +665,14 @@ it is not possible to update only some elements of a vector (without updating th
 Types stored in a vector are not implicitly frozen, so if you want to store a frozen collection or
 frozen UDT in a vector, you need to explicitly wrap them using `frozen` keyword.
 
+.. note::
+
+   The main application of vectors is to support vector search capabilities, which
+   are supported in ScyllaDB Cloud only in clusters that have the Vector Search feature enabled.
+   Note that Vector Search clusters do not support all ScyllaDB features (e.g., tracing, TTL, paging, and grouping). More information
+   about Vector Search is available in the
+   `ScyllaDB Cloud documentation <https://cloud.docs.scylladb.com/stable/vector-search/>`_.
+
 .. .. _custom-types:
 
 .. Custom Types

docs/dev/object_storage.md

@@ -221,6 +221,87 @@ scylla-bucket/prefix/
 ```
 See the API [documentation](#copying-sstables-on-s3-backup) for more details about the actual backup request.
 
+### The snapshot manifest
+
+Each table snapshot directory contains a manifest.json file that lists the contents of the snapshot and some metadata.
+The json structure is as follows:
+```
+{
+  "manifest": {
+    "version": "1.0",
+    "scope": "node"
+  },
+  "node": {
+    "host_id": "<UUID>",
+    "datacenter": "mydc",
+    "rack": "myrack"
+  },
+  "snapshot": {
+    "name": "snapshot name",
+    "created_at": seconds_since_epoch,
+    "expires_at": seconds_since_epoch | null,
+  },
+  "table": {
+    "keyspace_name": "my_keyspace",
+    "table_name": "my_table",
+    "table_id": "<UUID>",
+    "tablets_type": "none|powof2",
+    "tablet_count": N
+  },
+  "sstables": [
+    {
+      "id": "67e35000-d8c6-11f0-9599-060de9f3bd1b",
+      "toc_name": "me-3gw7_0ndy_3wlq829wcsddgwha1n-big-TOC.txt",
+      "data_size": 75,
+      "index_size": 8,
+      "first_token": -8629266958227979430,
+      "last_token": 9168982884335614769,
+    },
+    {
+      "id": "67e35000-d8c6-11f0-85dc-0625e9f3bd1b",
+      "toc_name": "me-3gw7_0ndy_3wlq821a6cqlbmxrtn-big-TOC.txt",
+      "data_size": 73,
+      "index_size": 8,
+      "first_token": 221146791717891383,
+      "last_token": 7354559975791427036,
+    },
+    ...
+  ],
+  "files": [ ... ]
+}
+
+The `manifest` member contains the following attributes:
+- `version` - respresenting the version of the manifest itself. It is incremented when members are added or removed from the manifest.
+- `scope` - the scope of metadata stored in this manifest file.  The following scopes are supported:
+    - `node` - the manifest describes all SSTables owned by this node in this snapshot.
+
+The `node` member contains metadata about this node that enables datacenter- or rack-aware restore.
+- `host_id` - is the node's unique host_id (a UUID).
+- `datacenter` - is the node's datacenter.
+- `rack` - is the node's rack.
+
+The `snapshot` member contains metadata about the snapshot.
+- `name` - is the snapshot name (a.k.a. `tag`)
+- `created_at` - is the time when the snapshot was created.
+- `expires_at` - is an optional time when the snapshot expires and can be dropped, if a TTL was set for the snapshot.  If there is no TTL, `expires_at` may be omitted, set to null, or set to 0.
+
+The `table` member contains metadata about the table being snapshot.
+- `keyspace_name` and `table_name` - are self-explanatory.
+- `table_id` - a universally unique identifier (UUID) of the table set when the table is created.
+- `tablets_type`:
+    - `none` - if the keyspace uses vnodes replication
+    - `powof2` - if the keyspace uses tables replication, and the tablet token ranges are based on powers of 2.
+- `tablet_count` - Optional. If `tablets_type` is not `none`, contains the number of tablets allcated in the table. If `tablets_type` is `powof2`, tablet_count would be a power of 2.
+
+The `sstables` member is a list containing metadata about the SSTables in the snapshot.
+- `id` - is the STable's unique id (a UUID).  It is carried over with the SSTable when it's streamed as part of tablet migration, even if it gets a new generation.
+- `toc_name` - is the name of the SSTable Table Of Contents (TOC) component.
+- `data_size` and `index_size` - are the sizes of the SSTable's data and index components, respectively.  They can be used to estimate how much disk space is needed for restore.
+- `first_token` and `last_token` - are the first and last tokens in the SSTable, respectively.  They can be used to determine if a SSTable is fully contained in a (tablet) token range to enable efficient file-based streaming of the SSTable.
+
+The optional `files` member may contain a list of non-SSTable files included in the snapshot directory, not including the manifest.json file and schema.cql.
+```
+
 3. `CREATE KEYSPACE` with S3/GS storage
 
 When creating a keyspace with S3/GS storage, the data is stored under the bucket passed as argument to the `CREATE KEYSPACE` statement.  

docs/dev/reader-concurrency-semaphore.md

@@ -78,6 +78,7 @@ Permits are in one of the following states:
 * `active/await` - a previously `active/need_cpu` permit, which needs something other than CPU to proceed, it is waiting on I/O or a remote shards, other permits can be admitted while the permit is in this state, pending resource availability;
 * `inactive` - the permit was marked inactive, it can be evicted to make room for admitting more permits if needed;
 * `evicted` - a former inactive permit which was evicted, the permit has to undergo admission again for the read to resume;
+* `preemptive_aborted` - the permit timed out or was rejected during admission as it was detected the read might time out later during execution;
 
 Note that some older releases will have different names for some of these states or lack some of the states altogether:
 

docs/dev/size-based-load-balancing.md

@@ -6,10 +6,10 @@ same amount of disk space. This means that the number of tablets located on a no
 proportional to the gross disk capacity of that node. Because the used disk space of
 different tablets can vary greatly, this could create imbalance in disk utilization.
 
-Size based load balancing aims to achieve better disk utilization accross nodes in a
+Size based load balancing aims to achieve better disk utilization across nodes in a
 cluster. The load balancer will continuously gather information about available disk
 space and tablet sizes from all the nodes. It then incrementally computes tablet
-migration plans which equalize disk utilization accross the cluster.
+migration plans which equalize disk utilization across the cluster.
 
 # Basic operation
 
@@ -75,7 +75,7 @@ migrations), and will wait for correct tablet sizes to arrive after the next ``l
 refresh by the topology coordinator.
 
 One exception to this are nodes which have been excluded from the cluster. These nodes
-are down and therefor are not able to send fresh ``load_stats``. But they have to be drained
+are down and therefore are not able to send fresh ``load_stats``. But they have to be drained
 of their tablets (via tablet rebuild), and the balancer must do this even with incomplete
 tablet data. So, only excluded nodes are allowed to have missing tablet sizes.
 

docs/dev/system_keyspace.md

@@ -357,6 +357,7 @@ Schema:
 CREATE TABLE system.load_per_node (
     node uuid PRIMARY KEY,
     dc text,
+    effective_capacity bigint,
     rack text,
     storage_allocated_load bigint,
     storage_allocated_utilization double,
@@ -372,6 +373,7 @@ Columns:
 * `storage_allocated_load` - Disk space allocated for tablets, assuming each tablet has a fixed size (target_tablet_size).
 * `storage_allocated_utilization` - Fraction of node's disk capacity taken for `storage_allocated_load`, where 1.0 means full utilization.
 * `storage_capacity` - Total disk capacity in bytes. Used to compute `storage_allocated_utilization`. By default equal to file system's capacity.
+* `effective_capacity` - Sum of available disk space and tablet sizes on a node. Used to compute load on a node for size based balancing.
 * `storage_load` - Disk space allocated for tablets, computed with actual tablet sizes. Can be null if some of the tablet sizes are not known.
 * `storage_utilization` - Fraction of node's disk capacity taken for `storage_load` (with actual tablet sizes), where 1.0 means full utilization. Can be null if some of the tablet sizes are not known.
 * `tablets_allocated` - Number of tablet replicas on the node. Migrating tablets are accounted as if migration already finished.

docs/dev/testing.md

@@ -124,6 +124,7 @@ There are several test directories that are excluded from orchestration by `test
 - test/cql
 - test/cqlpy
 - test/rest_api
+- test/scylla_gdb
 
 This means that `test.py` will not run tests directly, but will delegate all work to `pytest`.
 That's why all these directories do not have `suite.yaml` files.

docs/dev/topology-over-raft.md

@@ -46,14 +46,11 @@ stateDiagram-v2
     state replacing {
         rp_join_group0 : join_group0
         rp_left_token_ring : left_token_ring
-        rp_tablet_draining : tablet_draining 
         rp_write_both_read_old : write_both_read_old
         rp_write_both_read_new : write_both_read_new
         [*] --> rp_join_group0
         rp_join_group0 --> rp_left_token_ring: rollback
-        rp_join_group0 --> rp_tablet_draining
-        rp_tablet_draining --> rp_write_both_read_old
-        rp_tablet_draining --> rp_left_token_ring: rollback
+        rp_join_group0 --> rp_write_both_read_old
         rp_join_group0 --> [*]: rejected
         rp_write_both_read_old --> rp_write_both_read_new: streaming completed
         rp_write_both_read_old --> rp_left_token_ring: rollback
@@ -69,34 +66,34 @@ stateDiagram-v2
     normal --> decommissioning: leave
     normal --> removing: remove
     state decommissioning {
+        de_tablet_migration0 : tablet_migration (draining)
+        de_tablet_migration1 : tablet_migration
+        [*] --> de_tablet_migration0
+        de_tablet_migration0 --> [*]: aborted
         de_left_token_ring : left_token_ring
-        de_tablet_draining : tablet_draining 
-        de_tablet_migration : tablet_migration
         de_write_both_read_old: write_both_read_old
         de_write_both_read_new : write_both_read_new
         de_rollback_to_normal : rollback_to_normal
-        [*] --> de_tablet_draining
-        de_tablet_draining --> de_rollback_to_normal: rollback
-        de_rollback_to_normal --> de_tablet_migration
-        de_tablet_draining --> de_write_both_read_old
-        de_tablet_migration --> [*] 
+        de_rollback_to_normal --> de_tablet_migration1
+        de_tablet_migration0 --> de_write_both_read_old
+        de_tablet_migration1 --> [*]
         de_write_both_read_old --> de_write_both_read_new: streaming completed
         de_write_both_read_old --> de_rollback_to_normal: rollback
         de_write_both_read_new --> de_left_token_ring
         de_left_token_ring --> [*]
     }
     state removing {
+        re_tablet_migration0 : tablet_migration (draining)
+        re_tablet_migration1 : tablet_migration
+        [*] --> re_tablet_migration0
+        re_tablet_migration0 --> [*]: aborted
         re_left_token_ring : left_token_ring
-        re_tablet_draining : tablet_draining
-        re_tablet_migration : tablet_migration
         re_write_both_read_old : write_both_read_old
         re_write_both_read_new : write_both_read_new
         re_rollback_to_normal : rollback_to_normal
-        [*] --> re_tablet_draining
-        re_tablet_draining --> re_rollback_to_normal: rollback
-        re_rollback_to_normal --> re_tablet_migration
-        re_tablet_migration --> [*]
-        re_tablet_draining --> re_write_both_read_old
+        re_rollback_to_normal --> re_tablet_migration1
+        re_tablet_migration1 --> [*]
+        re_tablet_migration0 --> re_write_both_read_old
         re_write_both_read_old --> re_write_both_read_new: streaming completed
         re_write_both_read_old --> re_rollback_to_normal: rollback
         re_write_both_read_new --> re_left_token_ring
@@ -181,6 +178,27 @@ are the currently supported global topology operations:
    contain replicas of the table being truncated. It uses [sessions](#Topology guards)
    to make sure that no stale RPCs are executed outside of the scope of the request.
 
+## Tablet draining
+
+Presence of node requests of type `leave` (decommission) and `remove` will cause the load
+balancer to start migrating tablets away from those nodes. Until they are drained
+of tablets, the requests are in paused state and are not picked by topology
+coordinator for execution.
+
+Paused requests are also pending, the "topology_request" field is engaged.
+The node's state is still `normal` when request is paused.
+
+Canceling the requests will stop the draining process, because absence of a request
+lifts the draining state on the node.
+
+When tablet scheduler is done with migrating all tablets away from a draining node,
+the associated request will be unpaused, and can be picked by topology coordinator
+for execution. This time it will enter the `write_both_read_old` transition and proceed
+with the vnode part.
+
+This allows multiple requests to drain tablets in parallel, and other requests to not be blocked
+by long `leave` and `remove` requests.
+
 ## Zero-token nodes
 
 Zero-token nodes (the nodes started with `join_ring=false`) never own tokens or become
@@ -221,12 +239,6 @@ that there are no tablet transitions in the system.
 
 Tablets are migrated in parallel and independently.
 
-There is a variant of tablet migration track called tablet draining track, which is invoked
-as a step of certain topology operations (e.g. decommission, removenode). Its goal is to readjust tablet replicas
-so that a given topology change can proceed. For example, when decommissioning a node, we
-need to migrate tablet replicas away from the node being decommissioned.
-Tablet draining happens before making changes to vnode-based replication.
-
 ## Node replace with tablets
 
 Tablet replicas on the replaced node are rebuilt after the replacing node is already in the normal state and

docs/features/automatic-repair.rst

@@ -0,0 +1,23 @@
+.. _automatic-repair:
+
+Automatic Repair
+================
+
+Traditionally, launching `repairs </operating-scylla/procedures/maintenance/repair>`_ in a ScyllaDB cluster is left to an external process, typically done via `Scylla Manager <https://manager.docs.scylladb.com/stable/repair/index.html>`_.
+
+Automatic repair offers built-in scheduling in ScyllaDB itself. If the time since the last repair is greater than the configured repair interval, ScyllaDB will start a repair for the tablet `tablet </architecture/tablets>`_ automatically.
+Repairs are spread over time and among nodes and shards, to avoid load spikes or any adverse effects on user workloads.
+
+To enable automatic repair, add this to the configuration (``scylla.yaml``):
+
+.. code-block:: yaml
+
+    auto_repair_enabled_default: true
+    auto_repair_threshold_default_in_seconds: 86400
+
+This will enable automatic repair for all tables with a repair period of 1 day. This configuration has to be set on each node, to an identical value.
+More featureful configuration methods will be implemented in the future.
+
+To disable, set ``auto_repair_enabled_default: false``.
+
+Automatic repair relies on `Incremental Repair </features/incremental-repair>`_ and as such it only works with `tablet </architecture/tablets>`_ tables.

docs/features/incremental-repair.rst

@@ -3,7 +3,7 @@
 Incremental Repair
 ==================
 
-ScyllaDB's standard repair process scans and processes all the data on a node, regardless of whether it has changed since the last repair. This operation can be resource-intensive and time-consuming. The Incremental Repair feature provides a much more efficient and lightweight alternative for maintaining data consistency.
+ScyllaDB's standard `repair </operating-scylla/procedures/maintenance/repair>`_ process scans and processes all the data on a node, regardless of whether it has changed since the last repair. This operation can be resource-intensive and time-consuming. The Incremental Repair feature provides a much more efficient and lightweight alternative for maintaining data consistency.
 
 The core idea of incremental repair is to repair only the data that has been written or changed since the last repair was run. It intelligently skips data that has already been verified, dramatically reducing the time, I/O, and CPU resources required for the repair operation.
 
@@ -28,8 +28,7 @@ Incremental Repair is only supported for tables that use the tablets architectur
 Incremental Repair Modes
 ------------------------
 
-Incremental is currently disabled by default. You can control its behavior for a given repair operation using the ``incremental_mode`` parameter.
-This is useful for enabling incremental repair, or in situations where you might need to force a full data validation.
+While incremental repair is the default and recommended mode, you can control its behavior for a given repair operation using the ``incremental_mode`` parameter. This is useful for situations where you might need to force a full data validation.
 
 The available modes are:
 
@@ -38,7 +37,12 @@ The available modes are:
 *   ``disabled``: Completely disables the incremental repair logic for the current operation. The repair behaves like a classic, non-incremental repair, and it does not read or update any incremental repair status markers.
 
 
-The incremental_mode parameter can be specified using nodetool cluster repair, e.g., nodetool cluster repair --incremental-mode incremental. It can also be specified with the REST API, e.g., curl -X POST "http://127.0.0.1:10000/storage_service/tablets/repair?ks=ks1&table=tb1&tokens=all&incremental_mode=incremental"
+The incremental_mode parameter can be specified using nodetool cluster repair, e.g., nodetool cluster repair --incremental-mode incremental.
+It can also be specified with the REST API, e.g.:
+
+.. code::
+
+    curl -X POST "http://127.0.0.1:10000/storage_service/tablets/repair?ks=ks1&table=tb1&tokens=all&incremental_mode=incremental"
 
 Benefits of Incremental Repair
 ------------------------------
@@ -47,6 +51,8 @@ Benefits of Incremental Repair
 *   **Reduced Resource Usage:** Consumes significantly less CPU, I/O, and network bandwidth compared to a full repair.
 *   **More Frequent Repairs:** The efficiency of incremental repair allows you to run it more frequently, ensuring a higher level of data consistency across your cluster at all times.
 
+Tables using Incremental Repair can schedule repairs in ScyllaDB itself, with `Automatic Repair </features/automatic-repair>`_.
+
 Notes
 -----
 

docs/features/index.rst

@@ -17,6 +17,7 @@ This document highlights ScyllaDB's key data modeling features.
    Workload Prioritization </features/workload-prioritization>
    Backup and Restore </features/backup-and-restore>
    Incremental Repair </features/incremental-repair/>
+   Automatic Repair </features/automatic-repair/>
    Vector Search </features/vector-search/>
 
 .. panel-box::
@@ -44,5 +45,7 @@ This document highlights ScyllaDB's key data modeling features.
   * :doc:`Incremental Repair </features/incremental-repair/>` provides a much more
     efficient and lightweight approach to maintaining data consistency by
     repairing only the data that has changed since the last repair.
+  * :doc:`Automatic Repair </features/automatic-repair/>` schedules and runs repairs
+    directly in ScyllaDB, without external schedulers.
   * :doc:`Vector Search in ScyllaDB </features/vector-search/>` enables
     similarity-based queries on vector embeddings.

docs/features/materialized-views.rst

@@ -86,7 +86,7 @@ Compaction Strategies with Materialized Views
 Materialized views, just like regular tables, use one of the available :doc:`compaction strategies </architecture/compaction/compaction-strategies>`.
 When a materialized view is created, it does not inherit its base table compaction strategy settings, because the data model
 of a view does not necessarily have the same characteristics as the one from its base table.
-Instead, the default compaction strategy (SizeTieredCompactionStrategy) is used.
+Instead, the default compaction strategy (IncrementalCompactionStrategy) is used.
 
 A compaction strategy for a new materialized view can be explicitly set during its creation, using the following command:
 

docs/getting-started/install-scylla/index.rst

@@ -24,9 +24,9 @@ Keep your versions up-to-date. The two latest versions are supported. Also, alwa
   :id: "getting-started"
   :class: my-panel
 
-  * :doc:`Launch ScyllaDB on AWS </getting-started/install-scylla/launch-on-aws>`
-  * :doc:`Launch ScyllaDB on GCP </getting-started/install-scylla/launch-on-gcp>`
-  * :doc:`Launch ScyllaDB on Azure </getting-started/install-scylla/launch-on-azure>`
+  * :doc:`Launch ScyllaDB |CURRENT_VERSION| on AWS </getting-started/install-scylla/launch-on-aws>`
+  * :doc:`Launch ScyllaDB |CURRENT_VERSION| on GCP </getting-started/install-scylla/launch-on-gcp>`
+  * :doc:`Launch ScyllaDB |CURRENT_VERSION| on Azure </getting-started/install-scylla/launch-on-azure>`
 
 
 .. panel-box::
@@ -35,7 +35,7 @@ Keep your versions up-to-date. The two latest versions are supported. Also, alwa
   :class: my-panel
 
   * :doc:`Install ScyllaDB with Web Installer (recommended) </getting-started/installation-common/scylla-web-installer>`
-  * :doc:`Install ScyllaDB Linux Packages </getting-started/install-scylla/install-on-linux>`
+  * :doc:`Install ScyllaDB |CURRENT_VERSION| Linux Packages </getting-started/install-scylla/install-on-linux>`
   * :doc:`Install scylla-jmx Package </getting-started/installation-common/install-jmx>`
   * :doc:`Install ScyllaDB Without root Privileges </getting-started/installation-common/unified-installer>`
   * :doc:`Air-gapped Server Installation </getting-started/installation-common/air-gapped-install>`

docs/getting-started/install-scylla/install-on-linux.rst

@@ -4,9 +4,9 @@
 .. |RHEL_EPEL_8| replace:: https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
 .. |RHEL_EPEL_9| replace:: https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm
 
-======================================
-Install ScyllaDB Linux Packages
-======================================
+========================================================
+Install ScyllaDB |CURRENT_VERSION| Linux Packages
+========================================================
 
 We recommend installing ScyllaDB using :doc:`ScyllaDB Web Installer for Linux </getting-started/installation-common/scylla-web-installer/>`,
 a platform-agnostic installation script, to install ScyllaDB on any supported Linux platform.
@@ -46,8 +46,8 @@ Install ScyllaDB
 
             .. code-block:: console
     
-               sudo gpg --homedir /tmp --no-default-keyring --keyring /tmp/temp.gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys a43e06657bac99e3
-               sudo gpg --homedir /tmp --no-default-keyring --keyring /tmp/temp.gpg --export --armor a43e06657bac99e3 | gpg --dearmor > /etc/apt/keyrings/scylladb.gpg
+               sudo gpg --homedir /tmp --no-default-keyring --keyring /tmp/temp.gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys c503c686b007f39e
+               sudo gpg --homedir /tmp --no-default-keyring --keyring /tmp/temp.gpg --export --armor c503c686b007f39e | gpg --dearmor > /etc/apt/keyrings/scylladb.gpg
 
             .. code-block:: console
                :substitutions:

docs/getting-started/install-scylla/launch-on-aws.rst

@@ -1,6 +1,6 @@
-==========================
-Launch ScyllaDB on AWS
-==========================
+===============================================
+Launch ScyllaDB |CURRENT_VERSION| on AWS
+===============================================
 
 This article will guide you through self-managed ScyllaDB deployment on AWS. For a fully-managed deployment of ScyllaDB 
 as-a-service, see `ScyllaDB Cloud documentation <https://cloud.docs.scylladb.com/>`_.

docs/getting-started/install-scylla/launch-on-azure.rst

@@ -1,6 +1,6 @@
-==========================
-Launch ScyllaDB on Azure
-==========================
+===============================================
+Launch ScyllaDB |CURRENT_VERSION| on Azure
+===============================================
 
 This article will guide you through self-managed ScyllaDB deployment on Azure. For a fully-managed deployment of ScyllaDB 
 as-a-service, see `ScyllaDB Cloud documentation <https://cloud.docs.scylladb.com/>`_.

docs/getting-started/install-scylla/launch-on-gcp.rst

@@ -1,6 +1,6 @@
-==========================
-Launch ScyllaDB on GCP
-==========================
+=============================================
+Launch ScyllaDB |CURRENT_VERSION| on GCP
+=============================================
 
 This article will guide you through self-managed ScyllaDB deployment on GCP. For a fully-managed deployment of ScyllaDB 
 as-a-service, see `ScyllaDB Cloud documentation <https://cloud.docs.scylladb.com/>`_.

docs/kb/index.rst

@@ -57,7 +57,6 @@ Knowledge Base
   * :doc:`Customizing CPUSET </kb/customizing-cpuset>`
   * :doc:`Recreate RAID devices </kb/raid-device>` - How to recreate your RAID devices without running scylla-setup
   * :doc:`Configure ScyllaDB Networking with Multiple NIC/IP Combinations </kb/yaml-address>` - examples for setting the different IP addresses in scylla.yaml
-  * :doc:`Updating the Mode in perftune.yaml After a ScyllaDB Upgrade </kb/perftune-modes-sync>`
   * :doc:`Kafka Sink Connector Quickstart </using-scylla/integrations/kafka-connector>`
   * :doc:`Kafka Sink Connector Configuration </using-scylla/integrations/sink-config>`
 

docs/kb/perftune-modes-sync.rst

@@ -1,48 +0,0 @@
-==============================================================
-Updating the Mode in perftune.yaml After a ScyllaDB Upgrade
-==============================================================
-
-We improved ScyllaDB's performance by `removing the rx_queues_count from the mode 
-condition <https://github.com/scylladb/seastar/pull/949>`_. As a result, ScyllaDB operates in 
-the ``sq_split`` mode instead of the ``mq`` mode (see :doc:`Seastar Perftune </operating-scylla/admin-tools/perftune>` for information about the modes).
-If you upgrade from an earlier version of ScyllaDB, your cluster's existing nodes may use the ``mq`` mode, 
-while new nodes will use the ``sq_split`` mode. As using different modes across one cluster is not recommended, 
-you should change the configuration to ensure that the ``sq_split`` mode is used on all nodes.
-
-This section describes how to update the `perftune.yaml` file to configure the ``sq_split`` mode on all nodes. 
-
-Procedure
-------------
-The examples below assume that you are using the default locations for storing data and the `scylla.yaml` file, 
-and that your NIC is ``eth5``. 
-
-#. Backup your old configuration. 
-
-   .. code-block:: console
-
-     sudo mv /etc/scylla.d/cpuset.conf /etc/scylla.d/cpuset.conf.old
-     sudo mv /etc/scylla.d/perftune.yaml /etc/scylla.d/perftune.yaml.old
-
-#. Create a new configuration.
-
-   .. code-block:: console
-
-     sudo scylla_sysconfig_setup --nic eth5 --homedir /var/lib/scylla --confdir /etc/scylla
-
-   A new ``/etc/scylla.d/cpuset.conf`` will be generated on the output.
-
-#. Compare the contents of the newly generated ``/etc/scylla.d/cpuset.conf`` with ``/etc/scylla.d/cpuset.conf.old`` you created in step 1.
-    
-     - If they are exactly the same, rename ``/etc/scylla.d/perftune.yaml.old`` you created in step 1 back to ``/etc/scylla.d/perftune.yaml`` and continue to the next node.
-     - If they are different, move on to the next steps.
-
-#. Restart the ``scylla-server`` service.
-
-   .. code-block:: console
-
-     nodetool drain
-     sudo systemctl restart scylla-server
-
-#. Wait for the service to become up and running (similarly to how it is done during a :doc:`rolling restart </operating-scylla/procedures/config-change/rolling-restart>`). It may take a considerable amount of time before the node is in the UN state due to resharding.
-
-#. Continue to the next node.

docs/operating-scylla/_common/networking-ports.rst

@@ -25,4 +25,8 @@ Port    Description                                   Protocol
 19142   Native shard-aware transport port  (ssl)         TCP
 ======  ============================================  ========
 
+If you're using ScyllaDB Alternator, ensure that the ports configured
+for Alternator with the ``alternator_port`` or ``alternator_https_port`` parameter
+are open. See :doc:`ScyllaDB Alternator </alternator/alternator>` for details.
+
 .. note:: For ScyllaDB Manager ports, see the `ScyllaDB Manager <https://manager.docs.scylladb.com/>`_ documentation.

docs/operating-scylla/admin-tools/scylla-sstable.rst

@@ -601,11 +601,7 @@ Scrub has several modes:
 * **segregate** - Fixes partition/row/mutation-fragment out-of-order errors by segregating the output into as many SStables as required so that the content of each output SStable is properly ordered.
 * **validate** - Validates the content of the SStable, reporting any corruptions found. Writes no output SStables. In this mode, scrub has the same outcome as the `validate operation <scylla-sstable-validate-operation_>`_ - and the validate operation is recommended over scrub.
 
-Output SStables are written to the directory specified via ``--output-directory``. They will be written with the ``BIG`` format and the highest supported SStable format, with generations chosen by scylla-sstable. Generations are chosen such
-that they are unique among the SStables written by the current scrub.
-
-The output directory must be empty; otherwise, scylla-sstable will abort scrub. You can allow writing to a non-empty directory by setting the ``--unsafe-accept-nonempty-output-dir`` command line flag.
-Note that scrub will be aborted if an SStable cannot be written because its generation clashes with a pre-existing SStable in the output directory.
+Output SStables are written to the directory specified via ``--output-dir``. They will be written with the ``BIG`` format and the highest supported SStable format, with random generation.
 
 validate-checksums
 ^^^^^^^^^^^^^^^^^^
@@ -870,7 +866,7 @@ The SSTable version to be used can be overridden with the ``--version`` flag, al
 SSTables which are already on the designated version are skipped. To force rewriting *all* SSTables, use the ``--all`` flag. 
 
 Output SSTables are written to the path provided by the ``--output-dir`` flag, or to the current directory if not specified.
-This directory is expected to exist and be empty. If not empty the tool will refuse to run. This can be overridden with the ``--unsafe-accept-nonempty-output-dir`` flag.
+This directory is expected to exist.
 
 It is strongly recommended to use the system schema tables as the schema source for this command, see the :ref:`schema options <scylla-sstable-schema>` for more details.
 A schema which is good enough to read the SSTable and dump its content, may not be good enough to write its content back verbatim.
@@ -882,6 +878,25 @@ But even an altered schema which changed only the table options can lead to data
 
 The mapping of input SSTables to output SSTables is printed to ``stdout``.
 
+filter
+^^^^^^
+
+Filter the SSTable(s), including/excluding specified partitions.
+
+Similar to ``scylla sstable dump-data --partition|--partition-file``, with some notable differences:
+
+* Instead of dumping the content to stdout, the filtered content is written back to SSTable(s) on disk.
+* Also supports negative filters (keep all partitions except the those specified).
+
+The partition list can be provided either via the ``--partition`` command line argument, or via a file path passed to the the ``--partitions-file`` argument. The file should contain one partition key per line.
+Partition keys should be provided in the hex format, as produced by `scylla types serialize </operating-scylla/admin-tools/scylla-types/>`_.
+
+With ``--include``, only the specified partitions are kept from the input SSTable(s). With ``--exclude``, the specified partitions are discarded and won't be written to the output SSTable(s).
+It is possible that certain input SSTable(s) won't have any content left after the filtering. These input SSTable(s) will not have a matching output SSTable.
+
+By default, each input sstable is filtered individually. Use ``--merge`` to filter the combined content of all input sstables, producing a single output SSTable.
+
+Output sstables use the latest supported sstable format (can be changed with ``--sstable-version``).
 
 Examples
 --------

docs/operating-scylla/admin-tools/task-manager.rst

@@ -93,6 +93,25 @@ API calls
 
 Cluster tasks are not unregistered from task manager with API calls.
 
+Node operations module
+----------------------
+
+There is a module named ``node_ops``, which allows tracking node operations: decommission, removenode, bootstrap, replace, rebuild.
+
+The ``type`` field designates the operation, and is one of:
+  - ``decommission``
+  - ``remove node``
+  - ``bootstrap``
+  - ``replace``
+  - ``rebuild``
+
+The ``scope`` and ``kind`` fields are set to ``cluster``.
+
+The ``entity`` field holds the host id of the node which is being operated on, as long as the request
+is not finished. In case of the ``replace`` operation, it will hold the host id of the replacing node.
+
+``decommission`` and ``remove node`` tasks are abortable, but only before they finish tablet migration.
+
 Tasks API
 ---------
 

docs/operating-scylla/nodetool-commands/cluster/repair.rst

@@ -55,7 +55,7 @@ ScyllaDB nodetool cluster repair command supports the following options:
 
      nodetool cluster repair --tablet-tokens 1,10474535988
 
-- ``--incremental-mode`` specifies the incremental repair mode. Can be 'disabled', 'incremental', or 'full'. 'incremental': The incremental repair logic is enabled. Unrepaired sstables will be included for repair. Repaired sstables will be skipped. The incremental repair states will be updated after repair. 'full': The incremental repair logic is enabled. Both repaired and unrepaired sstables will be included for repair. The incremental repair states will be updated after repair. 'disabled': The incremental repair logic is disabled completely. The incremental repair states, e.g., repaired_at in sstables and sstables_repaired_at in the system.tablets table, will not be updated after repair. When the option is not provided, it defaults to 'disabled'.
+- ``--incremental-mode`` specifies the incremental repair mode. Can be 'disabled', 'incremental', or 'full'. 'incremental': The incremental repair logic is enabled. Unrepaired sstables will be included for repair. Repaired sstables will be skipped. The incremental repair states will be updated after repair. 'full': The incremental repair logic is enabled. Both repaired and unrepaired sstables will be included for repair. The incremental repair states will be updated after repair. 'disabled': The incremental repair logic is disabled completely. The incremental repair states, e.g., repaired_at in sstables and sstables_repaired_at in the system.tablets table, will not be updated after repair. When the option is not provided, it defaults to incremental.
 
   For example:
 

docs/operating-scylla/nodetool-commands/decommission.rst

@@ -29,5 +29,13 @@ Before you run ``nodetool decommission``:
   request may fail.
   In such a case, ALTER the keyspace to reduce the RF before running ``nodetool decommission``.
 
+It's allowed to invoke ``nodetool decommission`` on multiple nodes in parallel. This will be faster than doing
+it sequentially if there is significant amount of data in tablet-based keyspaces, because
+tablets are migrated from nodes in parallel. Decommission process first migrates tablets away, and this
+part is done in parallel for all nodes being decommissioned. Then it does the vnode-based decommission, and
+this part is serialized with other vnode-based operations, including those from other decommission operations.
+
+Decommission which is still in the tablet draining phase can be canceled using Task Manager API.
+See :doc:`Task manager </operating-scylla/admin-tools/task-manager>`.
 
 .. include:: nodetool-index.rst

docs/operating-scylla/nodetool-commands/removenode.rst

@@ -56,6 +56,17 @@ To only mark the node as permanently down without doing actual removal, use :doc
 
 .. _removenode-ignore-dead-nodes:
 
+It's allowed to invoke ``nodetool removenode`` on multiple nodes in parallel. This will be faster than doing
+it sequentially if there is significant amount of data in tablet-based keyspaces, because
+tablets which belong to removed nodes will be rebuilt in parallel. Node removal first migrates tablets to new
+replicas, in parallel for all nodes being removed. Then does the part which executes
+removal for the vnode-based keyspaces, and this is serialized with other vnode-based operations, including
+those from other removenode operations.
+
+Removenode which is still in the tablet rebuild phase can be canceled using Task Manager API.
+Tablets which are already rebuilt will remain on their new replicas.
+See :doc:`Task manager </operating-scylla/admin-tools/task-manager>`.
+
 Ignoring Dead Nodes
 ---------------------