release: prepare for 4.1.11

sstable_writer may depend on the sstable throughout its whole lifecycle.
If the sstable is freed before the sstable_writer we might hit use-after-free
as in the follwing case:
```
std::_Deque_iterator<sstables::compression::segmented_offsets::bucket, sstables::compression::segmented_offsets::bucket&, sstables::compression::segmented_offsets::bucket*>::operator+=(long) at /usr/include/c++/10/bits/stl_deque.h:240
 (inlined by) std::operator+(std::_Deque_iterator<sstables::compression::segmented_offsets::bucket, sstables::compression::segmented_offsets::bucket&, sstables::compression::segmented_offsets::bucket*> const&, long) at /usr/include/c++/10/bits/stl_deque.h:378
 (inlined by) std::_Deque_iterator<sstables::compression::segmented_offsets::bucket, sstables::compression::segmented_offsets::bucket&, sstables::compression::segmented_offsets::bucket*>::operator[](long) const at /usr/include/c++/10/bits/stl_deque.h:252
 (inlined by) std::deque<sstables::compression::segmented_offsets::bucket, std::allocator<sstables::compression::segmented_offsets::bucket> >::operator[](unsigned long) at /usr/include/c++/10/bits/stl_deque.h:1327
 (inlined by) sstables::compression::segmented_offsets::push_back(unsigned long, sstables::compression::segmented_offsets::state&) at ./sstables/compress.cc:214
sstables::compression::segmented_offsets::writer::push_back(unsigned long) at ./sstables/compress.hh:123
 (inlined by) compressed_file_data_sink_impl<crc32_utils, (compressed_checksum_mode)1>::put(seastar::temporary_buffer<char>) at ./sstables/compress.cc:519
seastar::output_stream<char>::put(seastar::temporary_buffer<char>) at table.cc:?
 (inlined by) seastar::output_stream<char>::put(seastar::temporary_buffer<char>) at ././seastar/include/seastar/core/iostream-impl.hh:432
seastar::output_stream<char>::flush() at table.cc:?
seastar::output_stream<char>::close() at table.cc:?
sstables::file_writer::close() at sstables.cc:?
sstables::mc::writer::~writer() at writer.cc:?
 (inlined by) sstables::mc::writer::~writer() at ./sstables/mx/writer.cc:790
sstables::mc::writer::~writer() at writer.cc:?
flat_mutation_reader::impl::consumer_adapter<stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> > >::~consumer_adapter() at compaction.cc:?
 (inlined by) std::_Optional_payload_base<sstables::compaction_writer>::_M_destroy() at /usr/include/c++/10/optional:260
 (inlined by) std::_Optional_payload_base<sstables::compaction_writer>::_M_reset() at /usr/include/c++/10/optional:280
 (inlined by) std::_Optional_payload<sstables::compaction_writer, false, false, false>::~_Optional_payload() at /usr/include/c++/10/optional:401
 (inlined by) std::_Optional_base<sstables::compaction_writer, false, false>::~_Optional_base() at /usr/include/c++/10/optional:474
 (inlined by) std::optional<sstables::compaction_writer>::~optional() at /usr/include/c++/10/optional:659
 (inlined by) sstables::compacting_sstable_writer::~compacting_sstable_writer() at ./sstables/compaction.cc:229
 (inlined by) compact_mutation<(emit_only_live_rows)0, (compact_for_sstables)1, sstables::compacting_sstable_writer, noop_compacted_fragments_consumer>::~compact_mutation() at ././mutation_compactor.hh:468
 (inlined by) compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer>::~compact_for_compaction() at ././mutation_compactor.hh:538
 (inlined by) std::default_delete<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >::operator()(compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer>*) const at /usr/include/c++/10/bits/unique_ptr.h:85
 (inlined by) std::unique_ptr<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer>, std::default_delete<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> > >::~unique_ptr() at /usr/include/c++/10/bits/unique_ptr.h:361
 (inlined by) stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >::~stable_flattened_mutations_consumer() at ././mutation_reader.hh:342
 (inlined by) flat_mutation_reader::impl::consumer_adapter<stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> > >::~consumer_adapter() at ././flat_mutation_reader.hh:201
auto flat_mutation_reader::impl::consume_in_thread<stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >, flat_mutation_reader::no_filter>(stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >, flat_mutation_reader::no_filter, std::chrono::time_point<seastar::lowres_clock, std::chrono::duration<long, std::ratio<1l, 1000l> > >) at ././flat_mutation_reader.hh:272
 (inlined by) auto flat_mutation_reader::consume_in_thread<stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >, flat_mutation_reader::no_filter>(stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >, flat_mutation_reader::no_filter, std::chrono::time_point<seastar::lowres_clock, std::chrono::duration<long, std::ratio<1l, 1000l> > >) at ././flat_mutation_reader.hh:383
 (inlined by) auto flat_mutation_reader::consume_in_thread<stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> > >(stable_flattened_mutations_consumer<compact_for_compaction<sstables::compacting_sstable_writer, noop_compacted_fragments_consumer> >, std::chrono::time_point<seastar::lowres_clock, std::chrono::duration<long, std::ratio<1l, 1000l> > >) at ././flat_mutation_reader.hh:389
 (inlined by) seastar::future<void> sstables::compaction::setup<noop_compacted_fragments_consumer>(noop_compacted_fragments_consumer)::{lambda(flat_mutation_reader)#1}::operator()(flat_mutation_reader)::{lambda()#1}::operator()() at ./sstables/compaction.cc:612
```

What happens here is that:

    compressed_file_data_sink_impl(output_stream<char> out, sstables::compression* cm, sstables::local_compression lc)
            : _out(std::move(out))
            , _compression_metadata(cm)
            , _offsets(_compression_metadata->offsets.get_writer())
            , _compression(lc)
            , _full_checksum(ChecksumType::init_checksum())

_compression_metadata points to a buffer held by the sstable object.
and _compression_metadata->offsets.get_writer returns a writer that keeps
a reference to the segmented_offsets in the sstables::compression
that is used in the ~writer -> close path.

Fixes #7821

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Message-Id: <20201227145726.33319-1-bhalevy@scylladb.com>
(cherry picked from commit 8a745a0ee0)

.gitmodules

@@ -1,6 +1,6 @@
 [submodule "seastar"]
 	path = seastar
-	url = ../seastar
+	url = ../scylla-seastar
 	ignore = dirty
 [submodule "swagger-ui"]
 	path = swagger-ui
@@ -12,3 +12,6 @@
 [submodule "zstd"]
 	path = zstd
 	url = ../zstd
+[submodule "abseil"]
+	path = abseil
+	url = ../abseil-cpp

SCYLLA-VERSION-GEN

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 PRODUCT=scylla
-VERSION=666.development
+VERSION=4.1.11
 
 if test -f version
 then

alternator/auth.cc

@@ -129,7 +129,7 @@ future<std::string> get_key_from_roles(cql3::query_processor& qp, std::string us
             auth::meta::roles_table::qualified_name(), auth::meta::roles_table::role_col_name);
 
     auto cl = auth::password_authenticator::consistency_for_user(username);
-    auto timeout = auth::internal_distributed_timeout_config();
+    auto& timeout = auth::internal_distributed_timeout_config();
     return qp.execute_internal(query, cl, timeout, {sstring(username)}, true).then_wrapped([username = std::move(username)] (future<::shared_ptr<cql3::untyped_result_set>> f) {
         auto res = f.get0();
         auto salted_hash = std::optional<sstring>();

alternator/conditions.cc

@@ -141,6 +141,11 @@ struct nonempty : public size_check {
 
 // Check that array has the expected number of elements
 static void verify_operand_count(const rjson::value* array, const size_check& expected, const rjson::value& op) {
+    if (!array && expected(0)) {
+        // If expected() allows an empty AttributeValueList, it is also fine
+        // that it is missing.
+        return;
+    }
     if (!array || !array->IsArray()) {
         throw api_error("ValidationException", "With ComparisonOperator, AttributeValueList must be given and an array");
     }
@@ -365,31 +370,35 @@ bool check_compare(const rjson::value* v1, const rjson::value& v2, const Compara
 
 struct cmp_lt {
     template <typename T> bool operator()(const T& lhs, const T& rhs) const { return lhs < rhs; }
+    // We cannot use the normal comparison operators like "<" on the bytes
+    // type, because they treat individual bytes as signed but we need to
+    // compare them as *unsigned*. So we need a specialization for bytes.
+    bool operator()(const bytes& lhs, const bytes& rhs) const { return compare_unsigned(lhs, rhs) < 0; }
     static constexpr const char* diagnostic = "LT operator";
 };
 
 struct cmp_le {
-    // bytes only has <, so we cannot use <=.
-    template <typename T> bool operator()(const T& lhs, const T& rhs) const { return lhs < rhs || lhs == rhs; }
+    template <typename T> bool operator()(const T& lhs, const T& rhs) const { return lhs <= rhs; }
+    bool operator()(const bytes& lhs, const bytes& rhs) const { return compare_unsigned(lhs, rhs) <= 0; }
     static constexpr const char* diagnostic = "LE operator";
 };
 
 struct cmp_ge {
-    // bytes only has <, so we cannot use >=.
-    template <typename T> bool operator()(const T& lhs, const T& rhs) const { return rhs < lhs || lhs == rhs; }
+    template <typename T> bool operator()(const T& lhs, const T& rhs) const { return lhs >= rhs; }
+    bool operator()(const bytes& lhs, const bytes& rhs) const { return compare_unsigned(lhs, rhs) >= 0; }
     static constexpr const char* diagnostic = "GE operator";
 };
 
 struct cmp_gt {
-    // bytes only has <, so we cannot use >.
-    template <typename T> bool operator()(const T& lhs, const T& rhs) const { return rhs < lhs; }
+    template <typename T> bool operator()(const T& lhs, const T& rhs) const { return lhs > rhs; }
+    bool operator()(const bytes& lhs, const bytes& rhs) const { return compare_unsigned(lhs, rhs) > 0; }
     static constexpr const char* diagnostic = "GT operator";
 };
 
 // True if v is between lb and ub, inclusive.  Throws if lb > ub.
 template <typename T>
 bool check_BETWEEN(const T& v, const T& lb, const T& ub) {
-    if (ub < lb) {
+    if (cmp_lt()(ub, lb)) {
         throw api_error("ValidationException",
                         format("BETWEEN operator requires lower_bound <= upper_bound, but {} > {}", lb, ub));
     }

alternator/executor.cc

@@ -573,29 +573,66 @@ static bool validate_legal_tag_chars(std::string_view tag) {
     return std::all_of(tag.begin(), tag.end(), &is_legal_tag_char);
 }
 
+static const std::unordered_set<std::string_view> allowed_write_isolation_values = {
+    "f", "forbid", "forbid_rmw",
+    "a", "always", "always_use_lwt",
+    "o", "only_rmw_uses_lwt",
+    "u", "unsafe", "unsafe_rmw",
+};
+
 static void validate_tags(const std::map<sstring, sstring>& tags) {
-    static const std::unordered_set<std::string_view> allowed_values = {
-        "f", "forbid", "forbid_rmw",
-        "a", "always", "always_use_lwt",
-        "o", "only_rmw_uses_lwt",
-        "u", "unsafe", "unsafe_rmw",
-    };
     auto it = tags.find(rmw_operation::WRITE_ISOLATION_TAG_KEY);
     if (it != tags.end()) {
         std::string_view value = it->second;
-        elogger.warn("Allowed values count {} {}", value, allowed_values.count(value));
-        if (allowed_values.count(value) == 0) {
+        if (allowed_write_isolation_values.count(value) == 0) {
             throw api_error("ValidationException",
-                    format("Incorrect write isolation tag {}. Allowed values: {}", value, allowed_values));
+                    format("Incorrect write isolation tag {}. Allowed values: {}", value, allowed_write_isolation_values));
         }
     }
 }
 
+static rmw_operation::write_isolation parse_write_isolation(std::string_view value) {
+    if (!value.empty()) {
+        switch (value[0]) {
+        case 'f':
+            return rmw_operation::write_isolation::FORBID_RMW;
+        case 'a':
+            return rmw_operation::write_isolation::LWT_ALWAYS;
+        case 'o':
+            return rmw_operation::write_isolation::LWT_RMW_ONLY;
+        case 'u':
+            return rmw_operation::write_isolation::UNSAFE_RMW;
+        }
+    }
+    // Shouldn't happen as validate_tags() / set_default_write_isolation()
+    // verify allow only a closed set of values.
+    return rmw_operation::default_write_isolation;
+
+}
+// This default_write_isolation is always overwritten in main.cc, which calls
+// set_default_write_isolation().
+rmw_operation::write_isolation rmw_operation::default_write_isolation =
+        rmw_operation::write_isolation::LWT_ALWAYS;
+void rmw_operation::set_default_write_isolation(std::string_view value) {
+    if (value.empty()) {
+        throw std::runtime_error("When Alternator is enabled, write "
+                "isolation policy must be selected, using the "
+                "'--alternator-write-isolation' option. "
+                "See docs/alternator/alternator.md for instructions.");
+    }
+    if (allowed_write_isolation_values.count(value) == 0) {
+        throw std::runtime_error(format("Invalid --alternator-write-isolation "
+                "setting '{}'. Allowed values: {}.",
+                value, allowed_write_isolation_values));
+    }
+    default_write_isolation = parse_write_isolation(value);
+}
+
 // FIXME: Updating tags currently relies on updating schema, which may be subject
 // to races during concurrent updates of the same table. Once Scylla schema updates
 // are fixed, this issue will automatically get fixed as well.
 enum class update_tags_action { add_tags, delete_tags };
-static future<> update_tags(const rjson::value& tags, schema_ptr schema, std::map<sstring, sstring>&& tags_map, update_tags_action action) {
+static future<> update_tags(service::migration_manager& mm, const rjson::value& tags, schema_ptr schema, std::map<sstring, sstring>&& tags_map, update_tags_action action) {
     if (action == update_tags_action::add_tags) {
         for (auto it = tags.Begin(); it != tags.End(); ++it) {
             const rjson::value& key = (*it)["Key"];
@@ -622,24 +659,12 @@ static future<> update_tags(const rjson::value& tags, schema_ptr schema, std::ma
     }
     validate_tags(tags_map);
 
-    std::stringstream serialized_tags;
-    serialized_tags << '{';
-    for (auto& tag_entry : tags_map) {
-        serialized_tags << format("'{}':'{}',", tag_entry.first, tag_entry.second);
-    }
-    std::string serialized_tags_str = serialized_tags.str();
-    if (!tags_map.empty()) {
-        serialized_tags_str[serialized_tags_str.size() - 1] = '}'; // trims the last ',' delimiter
-    } else {
-        serialized_tags_str.push_back('}');
-    }
-
-    sstring req = format("ALTER TABLE \"{}\".\"{}\" WITH {} = {}",
-            schema->ks_name(), schema->cf_name(), tags_extension::NAME, serialized_tags_str);
-    return db::execute_cql(std::move(req)).discard_result();
+    schema_builder builder(schema);
+    builder.set_extensions(schema::extensions_map{{sstring(tags_extension::NAME), ::make_shared<tags_extension>(std::move(tags_map))}});
+    return mm.announce_column_family_update(builder.build(), false, std::vector<view_ptr>(), false);
 }
 
-static future<> add_tags(service::storage_proxy& proxy, schema_ptr schema, rjson::value& request_info) {
+static future<> add_tags(service::migration_manager& mm, service::storage_proxy& proxy, schema_ptr schema, rjson::value& request_info) {
     const rjson::value* tags = rjson::find(request_info, "Tags");
     if (!tags || !tags->IsArray()) {
         return make_exception_future<>(api_error("ValidationException", format("Cannot parse tags")));
@@ -649,7 +674,7 @@ static future<> add_tags(service::storage_proxy& proxy, schema_ptr schema, rjson
     }
 
     std::map<sstring, sstring> tags_map = get_tags_of_table(schema);
-    return update_tags(rjson::copy(*tags), schema, std::move(tags_map), update_tags_action::add_tags);
+    return update_tags(mm, rjson::copy(*tags), schema, std::move(tags_map), update_tags_action::add_tags);
 }
 
 future<executor::request_return_type> executor::tag_resource(client_state& client_state, service_permit permit, rjson::value request) {
@@ -661,7 +686,7 @@ future<executor::request_return_type> executor::tag_resource(client_state& clien
             return api_error("AccessDeniedException", "Incorrect resource identifier");
         }
         schema_ptr schema = get_table_from_arn(_proxy, std::string_view(arn->GetString(), arn->GetStringLength()));
-        add_tags(_proxy, schema, request).get();
+        add_tags(_mm, _proxy, schema, request).get();
         return json_string("");
     });
 }
@@ -682,7 +707,7 @@ future<executor::request_return_type> executor::untag_resource(client_state& cli
         schema_ptr schema = get_table_from_arn(_proxy, std::string_view(arn->GetString(), arn->GetStringLength()));
 
         std::map<sstring, sstring> tags_map = get_tags_of_table(schema);
-        update_tags(*tags, schema, std::move(tags_map), update_tags_action::delete_tags).get();
+        update_tags(_mm, *tags, schema, std::move(tags_map), update_tags_action::delete_tags).get();
         return json_string("");
     });
 }
@@ -710,6 +735,17 @@ future<executor::request_return_type> executor::list_tags_of_resource(client_sta
     return make_ready_future<executor::request_return_type>(make_jsonable(std::move(ret)));
 }
 
+static future<> wait_for_schema_agreement(db::timeout_clock::time_point deadline) {
+    return do_until([deadline] {
+        if (db::timeout_clock::now() > deadline) {
+            throw std::runtime_error("Unable to reach schema agreement");
+        }
+        return service::get_local_migration_manager().have_schema_agreement();
+    }, [] {
+        return seastar::sleep(500ms);
+    });
+}
+
 future<executor::request_return_type> executor::create_table(client_state& client_state, tracing::trace_state_ptr trace_state, service_permit permit, rjson::value request) {
     _stats.api_operations.create_table++;
     elogger.trace("Creating table {}", request);
@@ -903,9 +939,11 @@ future<executor::request_return_type> executor::create_table(client_state& clien
             }).then([this, table_info = std::move(table_info), schema] () mutable {
                 future<> f = make_ready_future<>();
                 if (rjson::find(table_info, "Tags")) {
-                    f = add_tags(_proxy, schema, table_info);
+                    f = add_tags(_mm, _proxy, schema, table_info);
                 }
-                return f.then([table_info = std::move(table_info), schema] () mutable {
+                return f.then([] {
+                    return wait_for_schema_agreement(db::timeout_clock::now() + 10s);
+                }).then([table_info = std::move(table_info), schema] () mutable {
                     rjson::value status = rjson::empty_object();
                     supplement_table_info(table_info, *schema);
                     rjson::set(status, "TableDescription", std::move(table_info));
@@ -933,15 +971,24 @@ class attribute_collector {
     void add(bytes&& name, atomic_cell&& cell) {
         collected.emplace(std::move(name), std::move(cell));
     }
+    void add(const bytes& name, atomic_cell&& cell) {
+        collected.emplace(name, std::move(cell));
+    }
 public:
     attribute_collector() : collected(attrs_type()->get_keys_type()->as_less_comparator()) { }
-    void put(bytes&& name, bytes&& val, api::timestamp_type ts) {
-        add(std::move(name), atomic_cell::make_live(*bytes_type, ts, std::move(val), atomic_cell::collection_member::yes));
+    void put(bytes&& name, const bytes& val, api::timestamp_type ts) {
+        add(std::move(name), atomic_cell::make_live(*bytes_type, ts, val, atomic_cell::collection_member::yes));
 
     }
+    void put(const bytes& name, const bytes& val, api::timestamp_type ts) {
+        add(name, atomic_cell::make_live(*bytes_type, ts, val, atomic_cell::collection_member::yes));
+    }
     void del(bytes&& name, api::timestamp_type ts) {
         add(std::move(name), atomic_cell::make_dead(ts, gc_clock::now()));
     }
+    void del(const bytes& name, api::timestamp_type ts) {
+        add(name, atomic_cell::make_dead(ts, gc_clock::now()));
+    }
     collection_mutation_description to_mut() {
         collection_mutation_description ret;
         for (auto&& e : collected) {
@@ -1021,7 +1068,7 @@ public:
     put_or_delete_item(const rjson::value& item, schema_ptr schema, put_item);
     // put_or_delete_item doesn't keep a reference to schema (so it can be
     // moved between shards for LWT) so it needs to be given again to build():
-    mutation build(schema_ptr schema, api::timestamp_type ts);
+    mutation build(schema_ptr schema, api::timestamp_type ts) const;
     const partition_key& pk() const { return _pk; }
     const clustering_key& ck() const { return _ck; }
 };
@@ -1050,7 +1097,7 @@ put_or_delete_item::put_or_delete_item(const rjson::value& item, schema_ptr sche
     }
 }
 
-mutation put_or_delete_item::build(schema_ptr schema, api::timestamp_type ts) {
+mutation put_or_delete_item::build(schema_ptr schema, api::timestamp_type ts) const {
     mutation m(schema, _pk);
     // If there's no clustering key, a tombstone should be created directly
     // on a partition, not on a clustering row - otherwise it will look like
@@ -1072,7 +1119,7 @@ mutation put_or_delete_item::build(schema_ptr schema, api::timestamp_type ts) {
     for (auto& c : *_cells) {
         const column_definition* cdef = schema->get_column_definition(c.column_name);
         if (!cdef) {
-            attrs_collector.put(std::move(c.column_name), std::move(c.value), ts);
+            attrs_collector.put(c.column_name, c.value, ts);
         } else {
             row.cells().apply(*cdef, atomic_cell::make_live(*cdef->type, ts, std::move(c.value)));
         }
@@ -1195,22 +1242,9 @@ rmw_operation::write_isolation rmw_operation::get_write_isolation_for_schema(sch
     const auto& tags = get_tags_of_table(schema);
     auto it = tags.find(WRITE_ISOLATION_TAG_KEY);
     if (it == tags.end() || it->second.empty()) {
-        // By default, fall back to always enforcing LWT
-        return write_isolation::LWT_ALWAYS;
-    }
-    switch (it->second[0]) {
-    case 'f':
-        return write_isolation::FORBID_RMW;
-    case 'a':
-        return write_isolation::LWT_ALWAYS;
-    case 'o':
-        return write_isolation::LWT_RMW_ONLY;
-    case 'u':
-        return write_isolation::UNSAFE_RMW;
-    default:
-        // In case of an incorrect tag, fall back to the safest option: LWT_ALWAYS
-        return write_isolation::LWT_ALWAYS;
+        return default_write_isolation;
     }
+    return parse_write_isolation(it->second);
 }
 
 // shard_for_execute() checks whether execute() must be called on a specific
@@ -1241,11 +1275,6 @@ std::optional<shard_id> rmw_operation::shard_for_execute(bool needs_read_before_
 // PutItem, DeleteItem). All these return nothing by default, but can
 // optionally return Attributes if requested via the ReturnValues option.
 static future<executor::request_return_type> rmw_operation_return(rjson::value&& attributes) {
-    // As an optimization, in the simple and common case that nothing is to be
-    // returned, quickly return an empty result:
-    if (attributes.IsNull()) {
-        return make_ready_future<executor::request_return_type>(json_string(""));
-    }
     rjson::value ret = rjson::empty_object();
     if (!attributes.IsNull()) {
         rjson::set(ret, "Attributes", std::move(attributes));
@@ -1261,7 +1290,7 @@ future<executor::request_return_type> rmw_operation::execute(service::storage_pr
         stats& stats) {
     if (needs_read_before_write) {
         if (_write_isolation == write_isolation::FORBID_RMW) {
-            throw api_error("ValidationException", "Read-modify-write operations not supported");
+            throw api_error("ValidationException", "Read-modify-write operations are disabled by 'forbid_rmw' write isolation policy. Refer to https://github.com/scylladb/scylla/blob/master/docs/alternator/alternator.md#write-isolation-policies for more information.");
         }
         stats.reads_before_write++;
         if (_write_isolation == write_isolation::UNSAFE_RMW) {
@@ -1370,7 +1399,7 @@ public:
                check_needs_read_before_write(_condition_expression) ||
                _returnvalues == returnvalues::ALL_OLD;
     }
-    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) override {
+    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) const override {
         std::unordered_set<std::string> used_attribute_values;
         std::unordered_set<std::string> used_attribute_names;
         if (!verify_expected(_request, previous_item) ||
@@ -1382,6 +1411,7 @@ public:
             // efficient than throwing an exception.
             return {};
         }
+        _return_attributes = {};
         if (_returnvalues == returnvalues::ALL_OLD && previous_item) {
             // previous_item is supposed to have been created with
             // describe_item(), so has the "Item" attribute:
@@ -1448,7 +1478,7 @@ public:
                 check_needs_read_before_write(_condition_expression) ||
                 _returnvalues == returnvalues::ALL_OLD;
     }
-    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) override {
+    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) const override {
         std::unordered_set<std::string> used_attribute_values;
         std::unordered_set<std::string> used_attribute_names;
         if (!verify_expected(_request, previous_item) ||
@@ -1460,6 +1490,7 @@ public:
             // efficient than throwing an exception.
             return {};
         }
+        _return_attributes = {};
         if (_returnvalues == returnvalues::ALL_OLD && previous_item) {
             rjson::value* item = rjson::find(*previous_item, "Item");
             if (item) {
@@ -1543,7 +1574,7 @@ public:
     virtual ~put_or_delete_item_cas_request() = default;
     virtual std::optional<mutation> apply(foreign_ptr<lw_shared_ptr<query::result>> qr, const query::partition_slice& slice, api::timestamp_type ts) override {
         std::optional<mutation> ret;
-        for (put_or_delete_item& mutation_builder : _mutation_builders) {
+        for (const put_or_delete_item& mutation_builder : _mutation_builders) {
             // We assume all these builders have the same partition.
             if (ret) {
                 ret->apply(mutation_builder.build(schema, ts));
@@ -2367,7 +2398,7 @@ public:
 
     update_item_operation(service::storage_proxy& proxy, rjson::value&& request);
     virtual ~update_item_operation() = default;
-    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) override;
+    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) const override;
     bool needs_read_before_write() const;
 };
 
@@ -2431,7 +2462,7 @@ update_item_operation::needs_read_before_write() const {
 }
 
 std::optional<mutation>
-update_item_operation::apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) {
+update_item_operation::apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) const {
     std::unordered_set<std::string> used_attribute_values;
     std::unordered_set<std::string> used_attribute_names;
     if (!verify_expected(_request, previous_item) ||
@@ -2811,6 +2842,7 @@ future<executor::request_return_type> executor::batch_get_item(client_state& cli
             [] (std::vector<std::tuple<std::string, std::optional<rjson::value>>> responses) {
         rjson::value response = rjson::empty_object();
         rjson::set(response, "Responses", rjson::empty_object());
+        rjson::set(response, "UnprocessedKeys", rjson::empty_object());
         for (auto& t : responses) {
             if (!response["Responses"].HasMember(std::get<0>(t).c_str())) {
                 rjson::set_with_string_name(response["Responses"], std::get<0>(t), rjson::empty_array());
@@ -3080,7 +3112,7 @@ static dht::partition_range calculate_pk_bound(schema_ptr schema, const column_d
     if (attrs.Size() != 1) {
         throw api_error("ValidationException", format("Only a single attribute is allowed for a hash key restriction: {}", attrs));
     }
-    bytes raw_value = pk_cdef.type->from_string(attrs[0][type_to_string(pk_cdef.type)].GetString());
+    bytes raw_value = get_key_from_typed_value(attrs[0], pk_cdef);
     partition_key pk = partition_key::from_singular(*schema, pk_cdef.type->deserialize(raw_value));
     auto decorated_key = dht::decorate_key(*schema, pk);
     if (op != comparison_operator_type::EQ) {
@@ -3105,7 +3137,7 @@ static query::clustering_range calculate_ck_bound(schema_ptr schema, const colum
     if (attrs.Size() != expected_attrs_size) {
         throw api_error("ValidationException", format("{} arguments expected for a sort key restriction: {}", expected_attrs_size, attrs));
     }
-    bytes raw_value = ck_cdef.type->from_string(attrs[0][type_to_string(ck_cdef.type)].GetString());
+    bytes raw_value = get_key_from_typed_value(attrs[0], ck_cdef);
     clustering_key ck = clustering_key::from_single_value(*schema, raw_value);
     switch (op) {
     case comparison_operator_type::EQ:
@@ -3119,7 +3151,7 @@ static query::clustering_range calculate_ck_bound(schema_ptr schema, const colum
     case comparison_operator_type::GT:
         return query::clustering_range::make_starting_with(query::clustering_range::bound(ck, false));
     case comparison_operator_type::BETWEEN: {
-        bytes raw_upper_limit = ck_cdef.type->from_string(attrs[1][type_to_string(ck_cdef.type)].GetString());
+        bytes raw_upper_limit = get_key_from_typed_value(attrs[1], ck_cdef);
         clustering_key upper_limit = clustering_key::from_single_value(*schema, raw_upper_limit);
         return query::clustering_range::make(query::clustering_range::bound(ck), query::clustering_range::bound(upper_limit));
     }
@@ -3132,9 +3164,7 @@ static query::clustering_range calculate_ck_bound(schema_ptr schema, const colum
         if (!ck_cdef.type->is_compatible_with(*utf8_type)) {
             throw api_error("ValidationException", format("BEGINS_WITH operator cannot be applied to type {}", type_to_string(ck_cdef.type)));
         }
-        std::string raw_upper_limit_str = attrs[0][type_to_string(ck_cdef.type)].GetString();
-        bytes raw_upper_limit = ck_cdef.type->from_string(raw_upper_limit_str);
-        return get_clustering_range_for_begins_with(std::move(raw_upper_limit), ck, schema, ck_cdef.type);
+        return get_clustering_range_for_begins_with(std::move(raw_value), ck, schema, ck_cdef.type);
     }
     default:
         throw api_error("ValidationException", format("Unknown primary key bound passed: {}", int(op)));

alternator/rmw_operation.hh

@@ -63,6 +63,10 @@ public:
 
     static write_isolation get_write_isolation_for_schema(schema_ptr schema);
 
+    static write_isolation default_write_isolation;
+public:
+    static void set_default_write_isolation(std::string_view mode);
+
 protected:
     // The full request JSON
     rjson::value _request;
@@ -83,7 +87,11 @@ protected:
     // When _returnvalues != NONE, apply() should store here, in JSON form,
     // the values which are to be returned in the "Attributes" field.
     // The default null JSON means do not return an Attributes field at all.
-    rjson::value _return_attributes;
+    // This field is marked "mutable" so that the const apply() can modify
+    // it (see explanation below), but note that because apply() may be
+    // called more than once, if apply() will sometimes set this field it
+    // must set it (even if just to the default empty value) every time.
+    mutable rjson::value _return_attributes;
 public:
     // The constructor of a rmw_operation subclass should parse the request
     // and try to discover as many input errors as it can before really
@@ -96,7 +104,12 @@ public:
     // conditional expression, apply() should return an empty optional.
     // apply() may throw if it encounters input errors not discovered during
     // the constructor.
-    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) = 0;
+    // apply() may be called more than once in case of contention, so it must
+    // not change the state saved in the object (issue #7218 was caused by
+    // violating this). We mark apply() "const" to let the compiler validate
+    // this for us. The output-only field _return_attributes is marked
+    // "mutable" above so that apply() can still write to it.
+    virtual std::optional<mutation> apply(std::unique_ptr<rjson::value> previous_item, api::timestamp_type ts) const = 0;
     // Convert the above apply() into the signature needed by cas_request:
     virtual std::optional<mutation> apply(foreign_ptr<lw_shared_ptr<query::result>> qr, const query::partition_slice& slice, api::timestamp_type ts) override;
     virtual ~rmw_operation() = default;

api/storage_service.cc

@@ -54,26 +54,22 @@ static sstring validate_keyspace(http_context& ctx, const parameters& param) {
     throw bad_param_exception("Keyspace " + param["keyspace"] + " Does not exist");
 }
 
-static std::vector<ss::token_range> describe_ring(const sstring& keyspace) {
-    std::vector<ss::token_range> res;
-    for (auto d : service::get_local_storage_service().describe_ring(keyspace)) {
-        ss::token_range r;
-        r.start_token = d._start_token;
-        r.end_token = d._end_token;
-        r.endpoints = d._endpoints;
-        r.rpc_endpoints = d._rpc_endpoints;
-        for (auto det : d._endpoint_details) {
-            ss::endpoint_detail ed;
-            ed.host = det._host;
-            ed.datacenter = det._datacenter;
-            if (det._rack != "") {
-                ed.rack = det._rack;
-            }
-            r.endpoint_details.push(ed);
+static ss::token_range token_range_endpoints_to_json(const dht::token_range_endpoints& d) {
+    ss::token_range r;
+    r.start_token = d._start_token;
+    r.end_token = d._end_token;
+    r.endpoints = d._endpoints;
+    r.rpc_endpoints = d._rpc_endpoints;
+    for (auto det : d._endpoint_details) {
+        ss::endpoint_detail ed;
+        ed.host = det._host;
+        ed.datacenter = det._datacenter;
+        if (det._rack != "") {
+            ed.rack = det._rack;
         }
-        res.push_back(r);
+        r.endpoint_details.push(ed);
     }
-    return res;
+    return r;
 }
 
 using ks_cf_func = std::function<future<json::json_return_type>(http_context&, std::unique_ptr<request>, sstring, std::vector<sstring>)>;
@@ -192,13 +188,13 @@ void set_storage_service(http_context& ctx, routes& r) {
         return make_ready_future<json::json_return_type>(res);
     });
 
-    ss::describe_any_ring.set(r, [&ctx](const_req req) {
-        return describe_ring("");
+    ss::describe_any_ring.set(r, [&ctx](std::unique_ptr<request> req) {
+        return make_ready_future<json::json_return_type>(stream_range_as_array(service::get_local_storage_service().describe_ring(""), token_range_endpoints_to_json));
     });
 
-    ss::describe_ring.set(r, [&ctx](const_req req) {
-        auto keyspace = validate_keyspace(ctx, req.param);
-        return describe_ring(keyspace);
+    ss::describe_ring.set(r, [&ctx](std::unique_ptr<request> req) {
+        auto keyspace = validate_keyspace(ctx, req->param);
+        return make_ready_future<json::json_return_type>(stream_range_as_array(service::get_local_storage_service().describe_ring(keyspace), token_range_endpoints_to_json));
     });
 
     ss::get_host_id_map.set(r, [&ctx](const_req req) {
@@ -273,8 +269,8 @@ void set_storage_service(http_context& ctx, routes& r) {
                 for (auto cf : column_families) {
                     column_families_vec.push_back(&db.find_column_family(keyspace, cf));
                 }
-                return parallel_for_each(column_families_vec, [&cm] (column_family* cf) {
-                    return cm.perform_cleanup(cf);
+                return parallel_for_each(column_families_vec, [&cm, &db] (column_family* cf) {
+                    return cm.perform_cleanup(db, cf);
                 });
             }).then([]{
                 return make_ready_future<json::json_return_type>(0);

cdc/cdc_partitioner.cc

@@ -40,7 +40,8 @@ static dht::token to_token(int64_t value) {
 }
 
 static dht::token to_token(bytes_view key) {
-    if (key.empty()) {
+    // Key should be 16 B long, of which first 8 B are used for token calculation
+    if (key.size() != 2*sizeof(int64_t)) {
         return dht::minimum_token();
     }
     return to_token(stream_id::token_from_bytes(key));

cdc/generation.hh

@@ -130,7 +130,7 @@ bool should_propose_first_generation(const gms::inet_address& me, const gms::gos
  */
 future<db_clock::time_point> get_local_streams_timestamp();
 
-/* Generate a new set of CDC streams and insert it into the distributed cdc_topology_description table.
+/* Generate a new set of CDC streams and insert it into the distributed cdc_generations table.
  * Returns the timestamp of this new generation.
  *
  * Should be called when starting the node for the first time (i.e., joining the ring).
@@ -159,9 +159,9 @@ db_clock::time_point make_new_cdc_generation(
 std::optional<db_clock::time_point> get_streams_timestamp_for(const gms::inet_address& endpoint, const gms::gossiper&);
 
 /* Inform CDC users about a generation of streams (identified by the given timestamp)
- * by inserting it into the cdc_description table.
+ * by inserting it into the cdc_streams table.
  *
- * Assumes that the cdc_topology_description table contains this generation.
+ * Assumes that the cdc_generations table contains this generation.
  *
  * Returning from this function does not mean that the table update was successful: the function
  * might run an asynchronous task in the background.

cdc/log.cc

@@ -1146,7 +1146,7 @@ public:
                     if (r.row().deleted_at()) {
                         touched_parts.set<stats::part_type::ROW_DELETE>();
                         cdc_op = operation::row_delete;
-                        if (pirow) {
+                        if (pirow && pikey) {
                             for (const column_definition& column: _schema->regular_columns()) {
                                 assert(pirow->has(column.name_as_text()));
                                 auto& cdef = *_log_schema->get_column_definition(log_data_column_name_bytes(column.name()));

compaction_strategy.hh

@@ -140,6 +140,9 @@ public:
     uint64_t adjust_partition_estimate(const mutation_source_metadata& ms_meta, uint64_t partition_estimate);
 
     reader_consumer make_interposer_consumer(const mutation_source_metadata& ms_meta, reader_consumer end_consumer);
+
+    // Returns whether or not interposer consumer is used by a given strategy.
+    bool use_interposer_consumer() const;
 };
 
 // Creates a compaction_strategy object from one of the strategies available.

configure.py

@@ -381,6 +381,7 @@ scylla_tests = set([
     'test/boost/view_schema_ckey_test',
     'test/boost/vint_serialization_test',
     'test/boost/virtual_reader_test',
+    'test/boost/stall_free_test',
     'test/manual/ec2_snitch_test',
     'test/manual/gce_snitch_test',
     'test/manual/gossip',
@@ -540,6 +541,7 @@ scylla_core = (['database.cc',
                 'sstables/compaction_strategy.cc',
                 'sstables/size_tiered_compaction_strategy.cc',
                 'sstables/leveled_compaction_strategy.cc',
+                'sstables/time_window_compaction_strategy.cc',
                 'sstables/compaction_manager.cc',
                 'sstables/integrity_checked_file_impl.cc',
                 'sstables/prepended_input_stream.cc',
@@ -1265,9 +1267,9 @@ def query_seastar_flags(pc_file, link_static_cxx=False):
     return cflags, libs
 
 for mode in build_modes:
-    seastar_cflags, seastar_libs = query_seastar_flags(pc[mode], link_static_cxx=args.staticcxx)
-    modes[mode]['seastar_cflags'] = seastar_cflags
-    modes[mode]['seastar_libs'] = seastar_libs
+    seastar_pc_cflags, seastar_pc_libs = query_seastar_flags(pc[mode], link_static_cxx=args.staticcxx)
+    modes[mode]['seastar_cflags'] = seastar_pc_cflags
+    modes[mode]['seastar_libs'] = seastar_pc_libs
 
 # We need to use experimental features of the zstd library (to use our own allocators for the (de)compression context),
 # which are available only when the library is linked statically.
@@ -1288,6 +1290,46 @@ def configure_zstd(build_dir, mode):
     os.makedirs(zstd_build_dir, exist_ok=True)
     subprocess.check_call(zstd_cmd, shell=False, cwd=zstd_build_dir)
 
+def configure_abseil(build_dir, mode):
+    abseil_build_dir = os.path.join(build_dir, mode, 'abseil')
+
+    abseil_cflags = seastar_cflags + ' ' + modes[mode]['cxx_ld_flags']
+    cmake_mode = MODE_TO_CMAKE_BUILD_TYPE[mode]
+    abseil_cmake_args = [
+        '-DCMAKE_BUILD_TYPE={}'.format(cmake_mode),
+        '-DCMAKE_INSTALL_PREFIX={}'.format(build_dir + '/inst'), # just to avoid a warning from absl
+        '-DCMAKE_C_COMPILER={}'.format(args.cc),
+        '-DCMAKE_CXX_COMPILER={}'.format(args.cxx),
+        '-DCMAKE_CXX_FLAGS_{}={}'.format(cmake_mode.upper(), abseil_cflags),
+    ]
+
+    abseil_cmd = ['cmake', '-G', 'Ninja', os.path.relpath('abseil', abseil_build_dir)] + abseil_cmake_args
+
+    os.makedirs(abseil_build_dir, exist_ok=True)
+    subprocess.check_call(abseil_cmd, shell=False, cwd=abseil_build_dir)
+
+abseil_libs = ['absl/' + lib for lib in [
+    'container/libabsl_hashtablez_sampler.a',
+    'container/libabsl_raw_hash_set.a',
+    'synchronization/libabsl_synchronization.a',
+    'synchronization/libabsl_graphcycles_internal.a',
+    'debugging/libabsl_stacktrace.a',
+    'debugging/libabsl_symbolize.a',
+    'debugging/libabsl_debugging_internal.a',
+    'debugging/libabsl_demangle_internal.a',
+    'time/libabsl_time.a',
+    'time/libabsl_time_zone.a',
+    'numeric/libabsl_int128.a',
+    'hash/libabsl_city.a',
+    'hash/libabsl_hash.a',
+    'base/libabsl_malloc_internal.a',
+    'base/libabsl_spinlock_wait.a',
+    'base/libabsl_base.a',
+    'base/libabsl_dynamic_annotations.a',
+    'base/libabsl_raw_logging_internal.a',
+    'base/libabsl_exponential_biased.a',
+    'base/libabsl_throw_delegate.a']]
+
 args.user_cflags += " " + pkg_config('jsoncpp', '--cflags')
 args.user_cflags += ' -march=' + args.target
 libs = ' '.join([maybe_static(args.staticyamlcpp, '-lyaml-cpp'), '-latomic', '-llz4', '-lz', '-lsnappy', pkg_config('jsoncpp', '--libs'),
@@ -1318,6 +1360,7 @@ if any(filter(thrift_version.startswith, thrift_boost_versions)):
 for pkg in pkgs:
     args.user_cflags += ' ' + pkg_config(pkg, '--cflags')
     libs += ' ' + pkg_config(pkg, '--libs')
+args.user_cflags += '-I abseil'
 user_cflags = args.user_cflags + ' -fvisibility=hidden'
 user_ldflags = args.user_ldflags + ' -fvisibility=hidden'
 if args.staticcxx:
@@ -1348,6 +1391,9 @@ else:
 for mode in build_modes:
     configure_zstd(outdir, mode)
 
+for mode in build_modes:
+    configure_abseil(outdir, mode)
+
 # configure.py may run automatically from an already-existing build.ninja.
 # If the user interrupts configure.py in the middle, we need build.ninja
 # to remain in a valid state.  So we write our output to a temporary
@@ -1485,6 +1531,8 @@ with open(buildfile_tmp, 'w') as f:
                 objs.extend(['$builddir/' + mode + '/' + artifact for artifact in [
                     'libdeflate/libdeflate.a',
                     'zstd/lib/libzstd.a',
+                ] + [
+                    'abseil/' + x for x in abseil_libs
                 ]])
                 objs.append('$builddir/' + mode + '/gen/utils/gz/crc_combine_table.o')
                 if binary in tests:
@@ -1638,6 +1686,12 @@ with open(buildfile_tmp, 'w') as f:
         f.write('  subdir = build/{mode}/zstd\n'.format(**locals()))
         f.write('  target = libzstd.a\n'.format(**locals()))
 
+        for lib in abseil_libs:
+            f.write('build build/{mode}/abseil/{lib}: ninja\n'.format(**locals()))
+            f.write('  pool = submodule_pool\n')
+            f.write('  subdir = build/{mode}/abseil\n'.format(**locals()))
+            f.write('  target = {lib}\n'.format(**locals()))
+
     mode = 'dev' if 'dev' in modes else modes[0]
     f.write('build checkheaders: phony || {}\n'.format(' '.join(['$builddir/{}/{}.o'.format(mode, hh) for hh in headers])))
 

cql3/functions/aggregate_fcts.cc

@@ -267,10 +267,13 @@ public:
     }
 };
 
-/// The same as `impl_max_function_for' but without knowledge of `Type'.
+/// The same as `impl_max_function_for' but without compile-time dependency on `Type'.
 class impl_max_dynamic_function final : public aggregate_function::aggregate {
+    data_type _io_type;
     opt_bytes _max;
 public:
+    impl_max_dynamic_function(data_type io_type) : _io_type(std::move(io_type)) {}
+
     virtual void reset() override {
         _max = {};
     }
@@ -278,12 +281,11 @@ public:
         return _max.value_or(bytes{});
     }
     virtual void add_input(cql_serialization_format sf, const std::vector<opt_bytes>& values) override {
-        if (!values[0]) {
+        if (values.empty() || !values[0]) {
             return;
         }
-        const auto val = *values[0];
-        if (!_max || *_max < val) {
-            _max = val;
+        if (!_max || _io_type->less(*_max, *values[0])) {
+            _max = values[0];
         }
     }
 };
@@ -298,10 +300,13 @@ public:
 };
 
 class max_dynamic_function final : public native_aggregate_function {
+    data_type _io_type;
 public:
-    max_dynamic_function(data_type io_type) : native_aggregate_function("max", io_type, { io_type }) {}
+    max_dynamic_function(data_type io_type)
+            : native_aggregate_function("max", io_type, { io_type })
+            , _io_type(std::move(io_type)) {}
     virtual std::unique_ptr<aggregate> new_aggregate() override {
-        return std::make_unique<impl_max_dynamic_function>();
+        return std::make_unique<impl_max_dynamic_function>(_io_type);
     }
 };
 
@@ -358,10 +363,13 @@ public:
     }
 };
 
-/// The same as `impl_min_function_for' but without knowledge of `Type'.
+/// The same as `impl_min_function_for' but without compile-time dependency on `Type'.
 class impl_min_dynamic_function final : public aggregate_function::aggregate {
+    data_type _io_type;
     opt_bytes _min;
 public:
+    impl_min_dynamic_function(data_type io_type) : _io_type(std::move(io_type)) {}
+
     virtual void reset() override {
         _min = {};
     }
@@ -369,12 +377,11 @@ public:
         return _min.value_or(bytes{});
     }
     virtual void add_input(cql_serialization_format sf, const std::vector<opt_bytes>& values) override {
-        if (!values[0]) {
+        if (values.empty() || !values[0]) {
             return;
         }
-        const auto val = *values[0];
-        if (!_min || val < *_min) {
-            _min = val;
+        if (!_min || _io_type->less(*values[0], *_min)) {
+            _min = values[0];
         }
     }
 };
@@ -389,10 +396,13 @@ public:
 };
 
 class min_dynamic_function final : public native_aggregate_function {
+    data_type _io_type;
 public:
-    min_dynamic_function(data_type io_type) : native_aggregate_function("min", io_type, { io_type }) {}
+    min_dynamic_function(data_type io_type)
+            : native_aggregate_function("min", io_type, { io_type })
+            , _io_type(std::move(io_type)) {}
     virtual std::unique_ptr<aggregate> new_aggregate() override {
-        return std::make_unique<impl_min_dynamic_function>();
+        return std::make_unique<impl_min_dynamic_function>(_io_type);
     }
 };
 

cql3/functions/castas_fcts.cc

@@ -88,16 +88,13 @@ static data_value castas_fctn_simple(data_value from) {
 template<typename ToType>
 static data_value castas_fctn_from_decimal_to_float(data_value from) {
     auto val_from = value_cast<big_decimal>(from);
-    boost::multiprecision::cpp_int ten(10);
-    boost::multiprecision::cpp_rational r = val_from.unscaled_value();
-    r /= boost::multiprecision::pow(ten, val_from.scale());
-    return static_cast<ToType>(r);
+    return static_cast<ToType>(val_from.as_rational());
 }
 
 static utils::multiprecision_int from_decimal_to_cppint(const data_value& from) {
     const auto& val_from = value_cast<big_decimal>(from);
-    boost::multiprecision::cpp_int ten(10);
-    return boost::multiprecision::cpp_int(val_from.unscaled_value() / boost::multiprecision::pow(ten, val_from.scale()));
+    auto r = val_from.as_rational();
+    return utils::multiprecision_int(numerator(r)/denominator(r));
 }
 
 template<typename ToType>

cql3/lists.cc

@@ -357,7 +357,12 @@ lists::setter_by_uuid::execute(mutation& m, const clustering_key_prefix& prefix,
 
     collection_mutation_description mut;
     mut.cells.reserve(1);
-    mut.cells.emplace_back(to_bytes(*index), params.make_cell(*ltype->value_comparator(), *value, atomic_cell::collection_member::yes));
+
+    if (!value) {
+        mut.cells.emplace_back(to_bytes(*index), params.make_dead_cell());
+    } else {
+        mut.cells.emplace_back(to_bytes(*index), params.make_cell(*ltype->value_comparator(), *value, atomic_cell::collection_member::yes));
+    }
 
     m.set_cell(prefix, column, mut.serialize(*ltype));
 }

cql3/restrictions/statement_restrictions.cc

@@ -417,7 +417,7 @@ std::vector<const column_definition*> statement_restrictions::get_column_defs_fo
                     _clustering_columns_restrictions->num_prefix_columns_that_need_not_be_filtered();
             for (auto&& cdef : _clustering_columns_restrictions->get_column_defs()) {
                 ::shared_ptr<single_column_restriction> restr;
-                if (single_pk_restrs) {
+                if (single_ck_restrs) {
                     auto it = single_ck_restrs->restrictions().find(cdef);
                     if (it != single_ck_restrs->restrictions().end()) {
                         restr = dynamic_pointer_cast<single_column_restriction>(it->second);
@@ -688,6 +688,11 @@ static query::range<bytes_view> to_range(const term_slice& slice, const query_op
         extract_bound(statements::bound::END));
 }
 
+static bool contains_without_wraparound(
+        const query::range<bytes_view>& range, bytes_view value, const serialized_tri_compare& cmp) {
+    return !range.is_wrap_around(cmp) && range.contains(value, cmp);
+}
+
 bool single_column_restriction::slice::is_satisfied_by(const schema& schema,
         const partition_key& key,
         const clustering_key_prefix& ckey,
@@ -702,13 +707,13 @@ bool single_column_restriction::slice::is_satisfied_by(const schema& schema,
         return false;
     }
     return cell_value->with_linearized([&] (bytes_view cell_value_bv) {
-        return to_range(_slice, options, _column_def.name_as_text()).contains(
+        return contains_without_wraparound(to_range(_slice, options, _column_def.name_as_text()),
                 cell_value_bv, _column_def.type->as_tri_comparator());
     });
 }
 
 bool single_column_restriction::slice::is_satisfied_by(bytes_view data, const query_options& options) const {
-    return to_range(_slice, options, _column_def.name_as_text()).contains(
+    return contains_without_wraparound(to_range(_slice, options, _column_def.name_as_text()),
             data, _column_def.type->underlying_type()->as_tri_comparator());
 }
 

cql3/statements/alter_table_statement.cc

@@ -207,6 +207,9 @@ void alter_table_statement::add_column(const schema& schema, const table& cf, sc
                 "because a collection with the same name and a different type has already been used in the past", column_name));
         }
     }
+    if (type->is_counter() && !schema.is_counter()) {
+        throw exceptions::configuration_exception(format("Cannot add a counter column ({}) in a non counter column family", column_name));
+    }
 
     cfm.with_column(column_name.name(), type, is_static ? column_kind::static_column : column_kind::regular_column);
 
@@ -222,7 +225,7 @@ void alter_table_statement::add_column(const schema& schema, const table& cf, sc
             schema_builder builder(view);
             if (view->view_info()->include_all_columns()) {
                 builder.with_column(column_name.name(), type);
-            } else if (view->view_info()->base_non_pk_columns_in_view_pk().empty()) {
+            } else if (!view->view_info()->has_base_non_pk_columns_in_view_pk()) {
                 db::view::create_virtual_column(builder, column_name.name(), type);
             }
             view_updates.push_back(view_ptr(builder.build()));

cql3/statements/batch_statement.cc

@@ -68,6 +68,7 @@ batch_statement::batch_statement(int bound_terms, type type_,
     , _has_conditions(boost::algorithm::any_of(_statements, [] (auto&& s) { return s.statement->has_conditions(); }))
     , _stats(stats)
 {
+    validate();
     if (has_conditions()) {
         // A batch can be created not only by raw::batch_statement::prepare, but also by
         // cql_server::connection::process_batch, which doesn't call any methods of
@@ -448,7 +449,6 @@ batch_statement::prepare(database& db, cql_stats& stats) {
     prep_attrs->collect_marker_specification(bound_names);
 
     cql3::statements::batch_statement batch_statement_(bound_names.size(), _type, std::move(statements), std::move(prep_attrs), stats);
-    batch_statement_.validate();
 
     std::vector<uint16_t> partition_key_bind_indices;
     if (!have_multiple_cfs && batch_statement_.get_statements().size() > 0) {

database.cc

@@ -113,11 +113,11 @@ make_flush_controller(const db::config& cfg, seastar::scheduling_group sg, const
 
 inline
 std::unique_ptr<compaction_manager>
-make_compaction_manager(const db::config& cfg, database_config& dbcfg, abort_source& as) {
+make_compaction_manager(const db::config& cfg, database_config& dbcfg) {
     if (cfg.compaction_static_shares() > 0) {
-        return std::make_unique<compaction_manager>(dbcfg.compaction_scheduling_group, service::get_local_compaction_priority(), dbcfg.available_memory, cfg.compaction_static_shares(), as);
+        return std::make_unique<compaction_manager>(dbcfg.compaction_scheduling_group, service::get_local_compaction_priority(), dbcfg.available_memory, cfg.compaction_static_shares());
     }
-    return std::make_unique<compaction_manager>(dbcfg.compaction_scheduling_group, service::get_local_compaction_priority(), dbcfg.available_memory, as);
+    return std::make_unique<compaction_manager>(dbcfg.compaction_scheduling_group, service::get_local_compaction_priority(), dbcfg.available_memory);
 }
 
 lw_shared_ptr<keyspace_metadata>
@@ -161,7 +161,7 @@ void keyspace::remove_user_type(const user_type ut) {
 
 utils::UUID database::empty_version = utils::UUID_gen::get_name_UUID(bytes{});
 
-database::database(const db::config& cfg, database_config dbcfg, service::migration_notifier& mn, gms::feature_service& feat, locator::token_metadata& tm, abort_source& as)
+database::database(const db::config& cfg, database_config dbcfg, service::migration_notifier& mn, gms::feature_service& feat, locator::token_metadata& tm)
     : _stats(make_lw_shared<db_stats>())
     , _cl_stats(std::make_unique<cell_locker_stats>())
     , _cfg(cfg)
@@ -198,7 +198,7 @@ database::database(const db::config& cfg, database_config dbcfg, service::migrat
     , _mutation_query_stage()
     , _apply_stage("db_apply", &database::do_apply)
     , _version(empty_version)
-    , _compaction_manager(make_compaction_manager(_cfg, dbcfg, as))
+    , _compaction_manager(make_compaction_manager(_cfg, dbcfg))
     , _enable_incremental_backups(cfg.incremental_backups())
     , _querier_cache(_read_concurrency_sem, dbcfg.available_memory * 0.04)
     , _large_data_handler(std::make_unique<db::cql_table_large_data_handler>(_cfg.compaction_large_partition_warning_threshold_mb()*1024*1024,
@@ -1324,7 +1324,7 @@ future<mutation> database::do_apply_counter_update(column_family& cf, const froz
             // counter state for each modified cell...
 
             tracing::trace(trace_state, "Reading counter values from the CF");
-            return counter_write_query(m_schema, cf.as_mutation_source(), m.decorated_key(), slice, trace_state)
+            return counter_write_query(m_schema, cf.as_mutation_source(), m.decorated_key(), slice, trace_state, timeout)
                     .then([this, &cf, &m, m_schema, timeout, trace_state] (auto mopt) {
                 // ...now, that we got existing state of all affected counter
                 // cells we can look for our shard in each of them, increment
@@ -1823,7 +1823,11 @@ future<> database::truncate(const keyspace& ks, column_family& cf, timestamp_fun
                             // TODO: indexes.
                             // Note: since discard_sstables was changed to only count tables owned by this shard,
                             // we can get zero rp back. Changed assert, and ensure we save at least low_mark.
-                            assert(low_mark <= rp || rp == db::replay_position());
+                            // #6995 - the assert below was broken in c2c6c71 and remained so for many years. 
+                            // We nowadays do not flush tables with sstables but autosnapshot=false. This means
+                            // the low_mark assertion does not hold, because we maybe/probably never got around to 
+                            // creating the sstables that would create them.
+                            assert(!should_flush || low_mark <= rp || rp == db::replay_position());
                             rp = std::max(low_mark, rp);
                             return truncate_views(cf, truncated_at, should_flush).then([&cf, truncated_at, rp] {
                                 // save_truncation_record() may actually fail after we cached the truncation time
@@ -2001,9 +2005,10 @@ flat_mutation_reader make_multishard_streaming_reader(distributed<database>& db,
             reader_concurrency_semaphore* semaphore;
         };
         distributed<database>& _db;
+        utils::UUID _table_id;
         std::vector<reader_context> _contexts;
     public:
-        explicit streaming_reader_lifecycle_policy(distributed<database>& db) : _db(db), _contexts(smp::count) {
+        streaming_reader_lifecycle_policy(distributed<database>& db, utils::UUID table_id) : _db(db), _table_id(table_id), _contexts(smp::count) {
         }
         virtual flat_mutation_reader create_reader(
                 schema_ptr schema,
@@ -2032,7 +2037,12 @@ flat_mutation_reader make_multishard_streaming_reader(distributed<database>& db,
             });
         }
         virtual reader_concurrency_semaphore& semaphore() override {
-            return *_contexts[this_shard_id()].semaphore;
+            const auto shard = this_shard_id();
+            if (!_contexts[shard].semaphore) {
+                auto& cf = _db.local().find_column_family(_table_id);
+                _contexts[shard].semaphore = &cf.streaming_read_concurrency_semaphore();
+            }
+            return *_contexts[shard].semaphore;
         }
     };
     auto ms = mutation_source([&db] (schema_ptr s,
@@ -2043,7 +2053,8 @@ flat_mutation_reader make_multishard_streaming_reader(distributed<database>& db,
             tracing::trace_state_ptr trace_state,
             streamed_mutation::forwarding,
             mutation_reader::forwarding fwd_mr) {
-        return make_multishard_combining_reader(make_shared<streaming_reader_lifecycle_policy>(db), std::move(s), pr, ps, pc,
+        auto table_id = s->id();
+        return make_multishard_combining_reader(make_shared<streaming_reader_lifecycle_policy>(db, table_id), std::move(s), pr, ps, pc,
                 std::move(trace_state), fwd_mr);
     });
     auto&& full_slice = schema->full_slice();

database.hh

@@ -55,6 +55,7 @@
 #include <limits>
 #include <cstddef>
 #include "schema_fwd.hh"
+#include "db/view/view.hh"
 #include "db/schema_features.hh"
 #include "gms/feature.hh"
 #include "timestamp.hh"
@@ -903,7 +904,7 @@ public:
     lw_shared_ptr<const sstable_list> get_sstables_including_compacted_undeleted() const;
     const std::vector<sstables::shared_sstable>& compacted_undeleted_sstables() const;
     std::vector<sstables::shared_sstable> select_sstables(const dht::partition_range& range) const;
-    std::vector<sstables::shared_sstable> candidates_for_compaction() const;
+    std::vector<sstables::shared_sstable> non_staging_sstables() const;
     std::vector<sstables::shared_sstable> sstables_need_rewrite() const;
     size_t sstables_count() const;
     std::vector<uint64_t> sstable_count_per_level() const;
@@ -1008,8 +1009,9 @@ public:
         return *_config.sstables_manager;
     }
 
+    // Reader's schema must be the same as the base schema of each of the views.
     future<> populate_views(
-            std::vector<view_ptr>,
+            std::vector<db::view::view_and_base>,
             dht::token base_token,
             flat_mutation_reader&&);
 
@@ -1026,7 +1028,7 @@ private:
             const io_priority_class& io_priority, query::partition_slice::option_set custom_opts) const;
     std::vector<view_ptr> affected_views(const schema_ptr& base, const mutation& update) const;
     future<> generate_and_propagate_view_updates(const schema_ptr& base,
-            std::vector<view_ptr>&& views,
+            std::vector<db::view::view_and_base>&& views,
             mutation&& m,
             flat_mutation_reader_opt existings) const;
 
@@ -1427,7 +1429,7 @@ public:
     void set_enable_incremental_backups(bool val) { _enable_incremental_backups = val; }
 
     future<> parse_system_tables(distributed<service::storage_proxy>&, distributed<service::migration_manager>&);
-    database(const db::config&, database_config dbcfg, service::migration_notifier& mn, gms::feature_service& feat, locator::token_metadata& tm, abort_source& as);
+    database(const db::config&, database_config dbcfg, service::migration_notifier& mn, gms::feature_service& feat, locator::token_metadata& tm);
     database(database&&) = delete;
     ~database();
 

db/batchlog_manager.cc

@@ -290,7 +290,7 @@ future<> db::batchlog_manager::replay_all_failed_batches() {
             mutation m(schema, key);
             auto now = service::client_state(service::client_state::internal_tag()).get_timestamp();
             m.partition().apply_delete(*schema, clustering_key_prefix::make_empty(), tombstone(now, gc_clock::now()));
-            return _qp.proxy().mutate_locally(m);
+            return _qp.proxy().mutate_locally(m, db::commitlog::force_sync::no);
         });
     };
 

db/commitlog/commitlog.cc

@@ -521,7 +521,7 @@ public:
             _segment_manager->totals.total_size_on_disk -= size_on_disk();
             _segment_manager->totals.total_size -= (size_on_disk() + _buffer.size_bytes());
             _segment_manager->add_file_to_delete(_file_name, _desc);
-        } else {
+        } else if (_segment_manager->cfg.warn_about_segments_left_on_disk_after_shutdown) {
             clogger.warn("Segment {} is dirty and is left on disk.", *this);
         }
     }

db/commitlog/commitlog.hh

@@ -137,6 +137,7 @@ public:
 
         bool reuse_segments = true;
         bool use_o_dsync = false;
+        bool warn_about_segments_left_on_disk_after_shutdown = true;
 
         const db::extensions * extensions = nullptr;
     };

db/commitlog/commitlog_replayer.cc

@@ -299,7 +299,7 @@ future<> db::commitlog_replayer::impl::process(stats* s, commitlog::buffer_and_r
                 mutation m(cf.schema(), fm.decorated_key(*cf.schema()));
                 converting_mutation_partition_applier v(cm, *cf.schema(), m.partition());
                 fm.partition().accept(cm, v);
-                return do_with(std::move(m), [&db, &cf] (mutation m) {
+                return do_with(std::move(m), [&db, &cf] (const mutation& m) {
                     return db.apply_in_memory(m, cf, db::rp_handle(), db::no_timeout);
                 });
             } else {

db/config.cc

@@ -681,7 +681,7 @@ db::config::config(std::shared_ptr<db::extensions> exts)
     , replace_address(this, "replace_address", value_status::Used, "", "The listen_address or broadcast_address of the dead node to replace. Same as -Dcassandra.replace_address.")
     , replace_address_first_boot(this, "replace_address_first_boot", value_status::Used, "", "Like replace_address option, but if the node has been bootstrapped successfully it will be ignored. Same as -Dcassandra.replace_address_first_boot.")
     , override_decommission(this, "override_decommission", value_status::Used, false, "Set true to force a decommissioned node to join the cluster")
-    , enable_repair_based_node_ops(this, "enable_repair_based_node_ops", liveness::LiveUpdate, value_status::Used, true, "Set true to use enable repair based node operations instead of streaming based")
+    , enable_repair_based_node_ops(this, "enable_repair_based_node_ops", liveness::LiveUpdate, value_status::Used, false, "Set true to use enable repair based node operations instead of streaming based")
     , ring_delay_ms(this, "ring_delay_ms", value_status::Used, 30 * 1000, "Time a node waits to hear from other nodes before joining the ring in milliseconds. Same as -Dcassandra.ring_delay_ms in cassandra.")
     , shadow_round_ms(this, "shadow_round_ms", value_status::Used, 300 * 1000, "The maximum gossip shadow round time. Can be used to reduce the gossip feature check time during node boot up.")
     , fd_max_interval_ms(this, "fd_max_interval_ms", value_status::Used, 2 * 1000, "The maximum failure_detector interval time in milliseconds. Interval larger than the maximum will be ignored. Larger cluster may need to increase the default.")
@@ -736,6 +736,7 @@ db::config::config(std::shared_ptr<db::extensions> exts)
     , alternator_https_port(this, "alternator_https_port", value_status::Used, 0, "Alternator API HTTPS port")
     , alternator_address(this, "alternator_address", value_status::Used, "0.0.0.0", "Alternator API listening address")
     , alternator_enforce_authorization(this, "alternator_enforce_authorization", value_status::Used, false, "Enforce checking the authorization header for every request in Alternator")
+    , alternator_write_isolation(this, "alternator_write_isolation", value_status::Used, "", "Default write isolation policy for Alternator")
     , abort_on_ebadf(this, "abort_on_ebadf", value_status::Used, true, "Abort the server on incorrect file descriptor access. Throws exception when disabled.")
     , redis_port(this, "redis_port", value_status::Used, 0, "Port on which the REDIS transport listens for clients.")
     , redis_ssl_port(this, "redis_ssl_port", value_status::Used, 0, "Port on which the REDIS TLS native transport listens for clients.")

db/config.hh

@@ -314,6 +314,8 @@ public:
     named_value<uint16_t> alternator_https_port;
     named_value<sstring> alternator_address;
     named_value<bool> alternator_enforce_authorization;
+    named_value<sstring> alternator_write_isolation;
+
     named_value<bool> abort_on_ebadf;
 
     named_value<uint16_t> redis_port;

db/consistency_level.cc

@@ -61,7 +61,8 @@ namespace db {
 logging::logger cl_logger("consistency");
 
 size_t quorum_for(const keyspace& ks) {
-    return (ks.get_replication_strategy().get_replication_factor() / 2) + 1;
+    size_t replication_factor = ks.get_replication_strategy().get_replication_factor();
+    return replication_factor ? (replication_factor / 2) + 1 : 0;
 }
 
 size_t local_quorum_for(const keyspace& ks, const sstring& dc) {
@@ -72,8 +73,8 @@ size_t local_quorum_for(const keyspace& ks, const sstring& dc) {
     if (rs.get_type() == replication_strategy_type::network_topology) {
         const network_topology_strategy* nrs =
             static_cast<const network_topology_strategy*>(&rs);
-
-        return (nrs->get_replication_factor(dc) / 2) + 1;
+        size_t replication_factor = nrs->get_replication_factor(dc);
+        return replication_factor ? (replication_factor / 2) + 1 : 0;
     }
 
     return quorum_for(ks);

db/hints/manager.cc

@@ -224,7 +224,9 @@ future<> manager::end_point_hints_manager::stop(drain should_drain) noexcept {
         with_lock(file_update_mutex(), [this] {
             if (_hints_store_anchor) {
                 hints_store_ptr tmp = std::exchange(_hints_store_anchor, nullptr);
-                return tmp->shutdown().finally([tmp] {});
+                return tmp->shutdown().finally([tmp] {
+                    return tmp->release();
+                }).finally([tmp] {});
             }
             return make_ready_future<>();
         }).handle_exception([&eptr] (auto e) { eptr = std::move(e); }).get();
@@ -326,6 +328,10 @@ future<db::commitlog> manager::end_point_hints_manager::add_store() noexcept {
             // HH doesn't utilize the flow that benefits from reusing segments.
             // Therefore let's simply disable it to avoid any possible confusion.
             cfg.reuse_segments = false;
+            // HH leaves segments on disk after commitlog shutdown, and later reads
+            // them when commitlog is re-created. This is expected to happen regularly
+            // during standard HH workload, so no need to print a warning about it.
+            cfg.warn_about_segments_left_on_disk_after_shutdown = false;
 
             return commitlog::create_commitlog(std::move(cfg)).then([this] (commitlog l) {
                 // add_store() is triggered every time hint files are forcefully flushed to I/O (every hints_flush_period).
@@ -352,7 +358,9 @@ future<> manager::end_point_hints_manager::flush_current_hints() noexcept {
         return futurize_invoke([this] {
             return with_lock(file_update_mutex(), [this]() -> future<> {
                 return get_or_load().then([] (hints_store_ptr cptr) {
-                    return cptr->shutdown();
+                    return cptr->shutdown().finally([cptr] {
+                        return cptr->release();
+                    }).finally([cptr] {});
                 }).then([this] {
                     // Un-hold the commitlog object. Since we are under the exclusive _file_update_mutex lock there are no
                     // other hints_store_ptr copies and this would destroy the commitlog shared value.
@@ -703,6 +711,7 @@ future<> manager::end_point_hints_manager::sender::send_one_hint(lw_shared_ptr<s
                 // Files are aggregated for at most manager::hints_timer_period therefore the oldest hint there is
                 // (last_modification - manager::hints_timer_period) old.
                 if (gc_clock::now().time_since_epoch() - secs_since_file_mod > gc_grace_sec - manager::hints_flush_period) {
+                    ctx_ptr->rps_set.erase(rp);
                     return make_ready_future<>();
                 }
 
@@ -725,6 +734,7 @@ future<> manager::end_point_hints_manager::sender::send_one_hint(lw_shared_ptr<s
                 manager_logger.debug("send_hints(): {} at {}: {}", fname, rp, e.what());
                 ++this->shard_stats().discarded;
             }
+            ctx_ptr->rps_set.erase(rp);
             return make_ready_future<>();
         }).finally([units = std::move(units), ctx_ptr] {});
     }).handle_exception([this, ctx_ptr] (auto eptr) {
@@ -810,7 +820,7 @@ void manager::end_point_hints_manager::sender::send_hints_maybe() noexcept {
     int replayed_segments_count = 0;
 
     try {
-        while (replay_allowed() && have_segments()) {
+        while (replay_allowed() && have_segments() && can_send()) {
             if (!send_one_file(*_segments_to_replay.begin())) {
                 break;
             }

db/schema_tables.cc

@@ -822,6 +822,14 @@ future<> merge_schema(distributed<service::storage_proxy>& proxy, gms::feature_s
     });
 }
 
+future<> recalculate_schema_version(distributed<service::storage_proxy>& proxy, gms::feature_service& feat) {
+    return merge_lock().then([&proxy, &feat] {
+        return update_schema_version_and_announce(proxy, feat.cluster_schema_features());
+    }).finally([] {
+        return merge_unlock();
+    });
+}
+
 future<> merge_schema(distributed<service::storage_proxy>& proxy, std::vector<mutation> mutations, bool do_flush)
 {
     return merge_lock().then([&proxy, mutations = std::move(mutations), do_flush] () mutable {
@@ -2905,10 +2913,6 @@ future<> maybe_update_legacy_secondary_index_mv_schema(service::migration_manage
     // format, where "token" is not marked as computed. Once we're sure that all indexes have their
     // columns marked as computed (because they were either created on a node that supports computed
     // columns or were fixed by this utility function), it's safe to remove this function altogether.
-    if (!db.features().cluster_supports_computed_columns()) {
-        return make_ready_future<>();
-    }
-
     if (v->clustering_key_size() == 0) {
         return make_ready_future<>();
     }

db/schema_tables.hh

@@ -170,6 +170,13 @@ future<> merge_schema(distributed<service::storage_proxy>& proxy, gms::feature_s
 
 future<> merge_schema(distributed<service::storage_proxy>& proxy, std::vector<mutation> mutations, bool do_flush);
 
+// Recalculates the local schema version and publishes it in gossip.
+//
+// It is safe to call concurrently with recalculate_schema_version() and merge_schema() in which case it
+// is guaranteed that the schema version we end up with after all calls will reflect the most recent state
+// of feature_service and schema tables.
+future<> recalculate_schema_version(distributed<service::storage_proxy>& proxy, gms::feature_service& feat);
+
 future<std::set<sstring>> merge_keyspaces(distributed<service::storage_proxy>& proxy, schema_result&& before, schema_result&& after);
 
 std::vector<mutation> make_create_keyspace_mutations(lw_shared_ptr<keyspace_metadata> keyspace, api::timestamp_type timestamp, bool with_tables_and_types_and_functions = true);

db/system_distributed_keyspace.cc

@@ -72,7 +72,7 @@ schema_ptr view_build_status() {
 }
 
 /* An internal table used by nodes to exchange CDC generation data. */
-schema_ptr cdc_topology_description() {
+schema_ptr cdc_generations() {
     thread_local auto schema = [] {
         auto id = generate_legacy_id(system_distributed_keyspace::NAME, system_distributed_keyspace::CDC_TOPOLOGY_DESCRIPTION);
         return schema_builder(system_distributed_keyspace::NAME, system_distributed_keyspace::CDC_TOPOLOGY_DESCRIPTION, {id})
@@ -108,7 +108,7 @@ schema_ptr cdc_desc() {
 static std::vector<schema_ptr> all_tables() {
     return {
         view_build_status(),
-        cdc_topology_description(),
+        cdc_generations(),
         cdc_desc(),
     };
 }
@@ -204,7 +204,7 @@ future<> system_distributed_keyspace::remove_view(sstring ks_name, sstring view_
             false).discard_result();
 }
 
-/* We want to make sure that writes/reads to/from cdc_topology_description and cdc_description
+/* We want to make sure that writes/reads to/from cdc_generations and cdc_streams
  * are consistent: a read following an acknowledged write to the same partition should contact
  * at least one of the replicas that the write contacted.
  * Normally we would achieve that by always using CL = QUORUM,

db/system_distributed_keyspace.hh

@@ -48,10 +48,10 @@ public:
     static constexpr auto VIEW_BUILD_STATUS = "view_build_status";
 
     /* Nodes use this table to communicate new CDC stream generations to other nodes. */
-    static constexpr auto CDC_TOPOLOGY_DESCRIPTION = "cdc_topology_description";
+    static constexpr auto CDC_TOPOLOGY_DESCRIPTION = "cdc_generations";
 
     /* This table is used by CDC clients to learn about avaliable CDC streams. */
-    static constexpr auto CDC_DESC = "cdc_description";
+    static constexpr auto CDC_DESC = "cdc_streams";
 
     /* Information required to modify/query some system_distributed tables, passed from the caller. */
     struct context {

db/view/view.cc

@@ -130,17 +130,90 @@ const column_definition* view_info::view_column(const column_definition& base_de
     return _schema.get_column_definition(base_def.name());
 }
 
-const std::vector<column_id>& view_info::base_non_pk_columns_in_view_pk() const {
+void view_info::set_base_info(db::view::base_info_ptr base_info) {
+    _base_info = std::move(base_info);
+}
+
+// A constructor for a base info that can facilitate reads and writes from the materialized view.
+db::view::base_dependent_view_info::base_dependent_view_info(schema_ptr base_schema, std::vector<column_id>&& base_non_pk_columns_in_view_pk)
+        : _base_schema{std::move(base_schema)}
+        , _base_non_pk_columns_in_view_pk{std::move(base_non_pk_columns_in_view_pk)}
+        , has_base_non_pk_columns_in_view_pk{!_base_non_pk_columns_in_view_pk.empty()}
+        , use_only_for_reads{false} {
+
+}
+
+// A constructor for a base info that can facilitate only reads from the materialized view.
+db::view::base_dependent_view_info::base_dependent_view_info(bool has_base_non_pk_columns_in_view_pk)
+        : _base_schema{nullptr}
+        , has_base_non_pk_columns_in_view_pk{has_base_non_pk_columns_in_view_pk}
+        , use_only_for_reads{true} {
+}
+
+const std::vector<column_id>& db::view::base_dependent_view_info::base_non_pk_columns_in_view_pk() const {
+    if (use_only_for_reads) {
+        on_internal_error(vlogger, "base_non_pk_columns_in_view_pk(): operation unsupported when initialized only for view reads.");
+    }
     return _base_non_pk_columns_in_view_pk;
 }
 
-void view_info::initialize_base_dependent_fields(const schema& base) {
+const schema_ptr& db::view::base_dependent_view_info::base_schema() const {
+    if (use_only_for_reads) {
+        on_internal_error(vlogger, "base_schema(): operation unsupported when initialized only for view reads.");
+    }
+    return _base_schema;
+}
+
+db::view::base_info_ptr view_info::make_base_dependent_view_info(const schema& base) const {
+    std::vector<column_id> base_non_pk_columns_in_view_pk;
+    bool has_base_non_pk_columns_in_view_pk = false;
+    bool can_only_read_from_view = false;
+
     for (auto&& view_col : boost::range::join(_schema.partition_key_columns(), _schema.clustering_key_columns())) {
+        if (view_col.is_computed()) {
+            // we are not going to find it in the base table...
+            continue;
+        }
         auto* base_col = base.get_column_definition(view_col.name());
         if (base_col && !base_col->is_primary_key()) {
-            _base_non_pk_columns_in_view_pk.push_back(base_col->id);
+            base_non_pk_columns_in_view_pk.push_back(base_col->id);
+            has_base_non_pk_columns_in_view_pk = true;
+        } else if (!base_col) {
+            // If we didn't find the column in the base column then it must have been deleted
+            // or not yet added (by alter command), this means it is for sure not a pk column
+            // in the base table. This can happen if the version of the base schema is not the
+            // one that the view was created with. Seting this schema as the base can't harm since
+            // if we got to such a situation then it means it is only going to be used for reading
+            // (computation of shadowable tombstones) and in that case the existence of such a column
+            // is the only thing that is of interest to us.
+            has_base_non_pk_columns_in_view_pk = true;
+            can_only_read_from_view = true;
+
+            // We can break the loop here since we have the info we wanted and the list
+            // of columns is not going to be reliable anyhow.
+            break;
         }
     }
+
+    if (can_only_read_from_view) {
+        return make_lw_shared<db::view::base_dependent_view_info>(has_base_non_pk_columns_in_view_pk);
+    } else {
+        return make_lw_shared<db::view::base_dependent_view_info>(base.shared_from_this(), std::move(base_non_pk_columns_in_view_pk));
+    }
+
+}
+
+bool view_info::has_base_non_pk_columns_in_view_pk() const {
+    // The base info is not always available, this is because
+    // the base info initialization is separate from the view
+    // info construction. If we are trying to get this info without
+    // initializing the base information it means that we have a
+    // schema integrity problem as the creator of owning view schema
+    // didn't make sure to initialize it with base information.
+    if (!_base_info) {
+        on_internal_error(vlogger, "Tried to perform a view query which is base info dependant without initializing it");
+    }
+    return _base_info->has_base_non_pk_columns_in_view_pk;
 }
 
 namespace db {
@@ -188,11 +261,11 @@ bool may_be_affected_by(const schema& base, const view_info& view, const dht::de
 }
 
 static bool update_requires_read_before_write(const schema& base,
-        const std::vector<view_ptr>& views,
+        const std::vector<view_and_base>& views,
         const dht::decorated_key& key,
         const rows_entry& update) {
     for (auto&& v : views) {
-        view_info& vf = *v->view_info();
+        view_info& vf = *v.view->view_info();
         if (may_be_affected_by(base, vf, key, update)) {
             return true;
         }
@@ -239,12 +312,14 @@ class view_updates final {
     view_ptr _view;
     const view_info& _view_info;
     schema_ptr _base;
+    base_info_ptr _base_info;
     std::unordered_map<partition_key, mutation_partition, partition_key::hashing, partition_key::equality> _updates;
 public:
-    explicit view_updates(view_ptr view, schema_ptr base)
-            : _view(std::move(view))
+    explicit view_updates(view_and_base vab)
+            : _view(std::move(vab.view))
             , _view_info(*_view->view_info())
-            , _base(std::move(base))
+            , _base(vab.base->base_schema())
+            , _base_info(vab.base)
             , _updates(8, partition_key::hashing(*_view), partition_key::equality(*_view)) {
     }
 
@@ -306,7 +381,7 @@ row_marker view_updates::compute_row_marker(const clustering_row& base_row) cons
     // they share liveness information. It's true especially in the only case currently allowed by CQL,
     // which assumes there's up to one non-pk column in the view key. It's also true in alternator,
     // which does not carry TTL information.
-    const auto& col_ids = _view_info.base_non_pk_columns_in_view_pk();
+    const auto& col_ids = _base_info->base_non_pk_columns_in_view_pk();
     if (!col_ids.empty()) {
         auto& def = _base->regular_column_at(col_ids[0]);
         // Note: multi-cell columns can't be part of the primary key.
@@ -537,7 +612,7 @@ void view_updates::delete_old_entry(const partition_key& base_key, const cluster
 
 void view_updates::do_delete_old_entry(const partition_key& base_key, const clustering_row& existing, const clustering_row& update, gc_clock::time_point now) {
     auto& r = get_view_row(base_key, existing);
-    const auto& col_ids = _view_info.base_non_pk_columns_in_view_pk();
+    const auto& col_ids = _base_info->base_non_pk_columns_in_view_pk();
     if (!col_ids.empty()) {
         // We delete the old row using a shadowable row tombstone, making sure that
         // the tombstone deletes everything in the row (or it might still show up).
@@ -678,7 +753,7 @@ void view_updates::generate_update(
         return;
     }
 
-    const auto& col_ids = _view_info.base_non_pk_columns_in_view_pk();
+    const auto& col_ids = _base_info->base_non_pk_columns_in_view_pk();
     if (col_ids.empty()) {
         // The view key is necessarily the same pre and post update.
         if (existing && existing->is_live(*_base)) {
@@ -932,11 +1007,16 @@ future<stop_iteration> view_update_builder::on_results() {
 
 future<std::vector<frozen_mutation_and_schema>> generate_view_updates(
         const schema_ptr& base,
-        std::vector<view_ptr>&& views_to_update,
+        std::vector<view_and_base>&& views_to_update,
         flat_mutation_reader&& updates,
         flat_mutation_reader_opt&& existings) {
-    auto vs = boost::copy_range<std::vector<view_updates>>(views_to_update | boost::adaptors::transformed([&] (auto&& v) {
-        return view_updates(std::move(v), base);
+    auto vs = boost::copy_range<std::vector<view_updates>>(views_to_update | boost::adaptors::transformed([&] (view_and_base v) {
+        if (base->version() != v.base->base_schema()->version()) {
+            on_internal_error(vlogger, format("Schema version used for view updates ({}) does not match the current"
+                                              " base schema version of the view ({}) for view {}.{} of {}.{}",
+                base->version(), v.base->base_schema()->version(), v.view->ks_name(), v.view->cf_name(), base->ks_name(), base->cf_name()));
+        }
+        return view_updates(std::move(v));
     }));
     auto builder = std::make_unique<view_update_builder>(base, std::move(vs), std::move(updates), std::move(existings));
     auto f = builder->build();
@@ -946,18 +1026,18 @@ future<std::vector<frozen_mutation_and_schema>> generate_view_updates(
 query::clustering_row_ranges calculate_affected_clustering_ranges(const schema& base,
         const dht::decorated_key& key,
         const mutation_partition& mp,
-        const std::vector<view_ptr>& views) {
+        const std::vector<view_and_base>& views) {
     std::vector<nonwrapping_range<clustering_key_prefix_view>> row_ranges;
     std::vector<nonwrapping_range<clustering_key_prefix_view>> view_row_ranges;
     clustering_key_prefix_view::tri_compare cmp(base);
     if (mp.partition_tombstone() || !mp.row_tombstones().empty()) {
         for (auto&& v : views) {
             // FIXME: #2371
-            if (v->view_info()->select_statement().get_restrictions()->has_unrestricted_clustering_columns()) {
+            if (v.view->view_info()->select_statement().get_restrictions()->has_unrestricted_clustering_columns()) {
                 view_row_ranges.push_back(nonwrapping_range<clustering_key_prefix_view>::make_open_ended_both_sides());
                 break;
             }
-            for (auto&& r : v->view_info()->partition_slice().default_row_ranges()) {
+            for (auto&& r : v.view->view_info()->partition_slice().default_row_ranges()) {
                 view_row_ranges.push_back(r.transform(std::mem_fn(&clustering_key_prefix::view)));
             }
         }
@@ -1720,7 +1800,7 @@ public:
             return stop_iteration::yes;
         }
 
-        _fragments_memory_usage += cr.memory_usage(*_step.base->schema());
+        _fragments_memory_usage += cr.memory_usage(*_step.reader.schema());
         _fragments.push_back(std::move(cr));
         if (_fragments_memory_usage > batch_memory_max) {
             // Although we have not yet completed the batch of base rows that
@@ -1740,10 +1820,14 @@ public:
         _builder._as.check();
         if (!_fragments.empty()) {
             _fragments.push_front(partition_start(_step.current_key, tombstone()));
+            auto base_schema = _step.base->schema();
+            auto views = with_base_info_snapshot(_views_to_build);
+            auto reader = make_flat_mutation_reader_from_fragments(_step.reader.schema(), std::move(_fragments));
+            reader.upgrade_schema(base_schema);
             _step.base->populate_views(
-                    _views_to_build,
+                    std::move(views),
                     _step.current_token(),
-                    make_flat_mutation_reader_from_fragments(_step.base->schema(), std::move(_fragments))).get();
+                    std::move(reader)).get();
             _fragments.clear();
             _fragments_memory_usage = 0;
         }
@@ -1890,5 +1974,11 @@ future<bool> check_needs_view_update_path(db::system_distributed_keyspace& sys_d
     });
 }
 
+std::vector<db::view::view_and_base> with_base_info_snapshot(std::vector<view_ptr> vs) {
+    return boost::copy_range<std::vector<db::view::view_and_base>>(vs | boost::adaptors::transformed([] (const view_ptr& v) {
+        return db::view::view_and_base{v, v->view_info()->base_info()};
+    }));
+}
+
 } // namespace view
 } // namespace db

db/view/view.hh

@@ -43,6 +43,46 @@ namespace db {
 
 namespace view {
 
+// Part of the view description which depends on the base schema version.
+//
+// This structure may change even though the view schema doesn't change, so
+// it needs to live outside view_ptr.
+struct base_dependent_view_info {
+private:
+    schema_ptr _base_schema;
+    // Id of a regular base table column included in the view's PK, if any.
+    // Scylla views only allow one such column, alternator can have up to two.
+    std::vector<column_id> _base_non_pk_columns_in_view_pk;
+public:
+    const std::vector<column_id>& base_non_pk_columns_in_view_pk() const;
+    const schema_ptr& base_schema() const;
+
+    // Indicates if the view hase pk columns which are not part of the base
+    // pk, it seems that !base_non_pk_columns_in_view_pk.empty() is the same,
+    // but actually there are cases where we can compute this boolean without
+    // succeeding to reliably build the former.
+    const bool has_base_non_pk_columns_in_view_pk;
+
+    // If base_non_pk_columns_in_view_pk couldn't reliably be built, this base
+    // info can't be used for computing view updates, only for reading the materialized
+    // view.
+    const bool use_only_for_reads;
+
+    // A constructor for a base info that can facilitate reads and writes from the materialized view.
+    base_dependent_view_info(schema_ptr base_schema, std::vector<column_id>&& base_non_pk_columns_in_view_pk);
+    // A constructor for a base info that can facilitate only reads from the materialized view.
+    base_dependent_view_info(bool has_base_non_pk_columns_in_view_pk);
+};
+
+// Immutable snapshot of view's base-schema-dependent part.
+using base_info_ptr = lw_shared_ptr<const base_dependent_view_info>;
+
+// Snapshot of the view schema and its base-schema-dependent part.
+struct view_and_base {
+    view_ptr view;
+    base_info_ptr base;
+};
+
 /**
  * Whether the view filter considers the specified partition key.
  *
@@ -92,7 +132,7 @@ bool clustering_prefix_matches(const schema& base, const partition_key& key, con
 
 future<std::vector<frozen_mutation_and_schema>> generate_view_updates(
         const schema_ptr& base,
-        std::vector<view_ptr>&& views_to_update,
+        std::vector<view_and_base>&& views_to_update,
         flat_mutation_reader&& updates,
         flat_mutation_reader_opt&& existings);
 
@@ -100,7 +140,7 @@ query::clustering_row_ranges calculate_affected_clustering_ranges(
         const schema& base,
         const dht::decorated_key& key,
         const mutation_partition& mp,
-        const std::vector<view_ptr>& views);
+        const std::vector<view_and_base>& views);
 
 struct wait_for_all_updates_tag {};
 using wait_for_all_updates = bool_class<wait_for_all_updates_tag>;
@@ -128,6 +168,13 @@ future<> mutate_MV(
  */
  void create_virtual_column(schema_builder& builder, const bytes& name, const data_type& type);
 
+/**
+ * Converts a collection of view schema snapshots into a collection of
+ * view_and_base objects, which are snapshots of both the view schema
+ * and the base-schema-dependent part of view description.
+ */
+std::vector<view_and_base> with_base_info_snapshot(std::vector<view_ptr>);
+
 }
 
 }

db/view/view_update_generator.cc

@@ -36,19 +36,25 @@ future<> view_update_generator::start() {
                 _pending_sstables.wait().get();
             }
 
+            // To ensure we don't race with updates, move the entire content
+            // into a local variable.
+            auto sstables_with_tables = std::exchange(_sstables_with_tables, {});
+
             // If we got here, we will process all tables we know about so far eventually so there
             // is no starvation
-            for (auto& t : _sstables_with_tables | boost::adaptors::map_keys) {
+            for (auto table_it = sstables_with_tables.begin(); table_it != sstables_with_tables.end(); table_it = sstables_with_tables.erase(table_it)) {
+                auto& [t, sstables] = *table_it;
                 schema_ptr s = t->schema();
 
-                // Copy what we have so far so we don't miss new updates
-                auto sstables = std::exchange(_sstables_with_tables[t], {});
+                vug_logger.trace("Processing {}.{}: {} sstables", s->ks_name(), s->cf_name(), sstables.size());
+
+                const auto num_sstables = sstables.size();
 
                 try {
-                    // temporary: need an sstable set for the flat mutation reader, but the
-                    // compaction_descriptor takes a vector. Soon this will become a compaction
-                    // so the transformation to the SSTable set will not be needed.
-                    auto ssts = make_lw_shared(t->get_compaction_strategy().make_sstable_set(s));
+                    // Exploit the fact that sstables in the staging directory
+                    // are usually non-overlapping and use a partitioned set for
+                    // the read.
+                    auto ssts = make_lw_shared(sstables::make_partitioned_sstable_set(s, make_lw_shared<sstable_list>(sstable_list{}), false));
                     for (auto& sst : sstables) {
                         ssts->insert(sst);
                     }
@@ -81,7 +87,7 @@ future<> view_update_generator::start() {
                     // Move from staging will be retried upon restart.
                     vug_logger.warn("Moving {} from staging failed: {}:{}. Ignoring...", s->ks_name(), s->cf_name(), std::current_exception());
                 }
-                _registration_sem.signal();
+                _registration_sem.signal(num_sstables);
             }
             // For each table, move the processed staging sstables into the table's base dir.
             for (auto it = _sstables_to_move.begin(); it != _sstables_to_move.end(); ) {

db/view/view_update_generator.hh

@@ -32,7 +32,10 @@
 namespace db::view {
 
 class view_update_generator {
+public:
     static constexpr size_t registration_queue_size = 5;
+
+private:
     database& _db;
     seastar::abort_source _as;
     future<> _started = make_ready_future<>();
@@ -51,6 +54,8 @@ public:
     future<> start();
     future<> stop();
     future<> register_staging_sstable(sstables::shared_sstable sst, lw_shared_ptr<table> table);
+
+    ssize_t available_register_units() const { return _registration_sem.available_units(); }
 private:
     bool should_throttle() const;
 };

dht/boot_strapper.cc

@@ -43,16 +43,29 @@
 #include "log.hh"
 #include "db/config.hh"
 #include "database.hh"
+#include "streaming/stream_reason.hh"
 
 static logging::logger blogger("boot_strapper");
 
 namespace dht {
 
-future<> boot_strapper::bootstrap() {
+future<> boot_strapper::bootstrap(streaming::stream_reason reason) {
     blogger.debug("Beginning bootstrap process: sorted_tokens={}", _token_metadata.sorted_tokens());
-
-    auto streamer = make_lw_shared<range_streamer>(_db, _token_metadata, _abort_source, _tokens, _address, "Bootstrap", streaming::stream_reason::bootstrap);
-    streamer->add_source_filter(std::make_unique<range_streamer::failure_detector_source_filter>(gms::get_local_gossiper().get_unreachable_members()));
+    sstring description;
+    if (reason == streaming::stream_reason::bootstrap) {
+        description = "Bootstrap";
+    } else if (reason == streaming::stream_reason::replace) {
+        description = "Replace";
+    } else {
+        return make_exception_future<>(std::runtime_error("Wrong stream_reason provided: it can only be replace or bootstrap"));
+    }
+    auto streamer = make_lw_shared<range_streamer>(_db, _token_metadata, _abort_source, _tokens, _address, description, reason);
+    auto nodes_to_filter = gms::get_local_gossiper().get_unreachable_members();
+    if (reason == streaming::stream_reason::replace && _db.local().get_replace_address()) {
+        nodes_to_filter.insert(_db.local().get_replace_address().value());
+    }
+    blogger.debug("nodes_to_filter={}", nodes_to_filter);
+    streamer->add_source_filter(std::make_unique<range_streamer::failure_detector_source_filter>(nodes_to_filter));
     auto keyspaces = make_lw_shared<std::vector<sstring>>(_db.local().get_non_system_keyspaces());
     return do_for_each(*keyspaces, [this, keyspaces, streamer] (sstring& keyspace_name) {
         auto& ks = _db.local().find_keyspace(keyspace_name);

dht/boot_strapper.hh

@@ -41,6 +41,7 @@
 #include "dht/i_partitioner.hh"
 #include <unordered_set>
 #include "database_fwd.hh"
+#include "streaming/stream_reason.hh"
 #include <seastar/core/distributed.hh>
 #include <seastar/core/abort_source.hh>
 
@@ -66,7 +67,7 @@ public:
         , _token_metadata(tmd) {
     }
 
-    future<> bootstrap();
+    future<> bootstrap(streaming::stream_reason reason);
 
     /**
      * if initialtoken was specified, use that (split on comma).

dht/range_streamer.cc

@@ -91,7 +91,16 @@ range_streamer::get_range_fetch_map(const std::unordered_map<dht::token_range, s
         }
 
         if (!found_source) {
-            throw std::runtime_error(format("unable to find sufficient sources for streaming range {} in keyspace {}", range_, keyspace));
+            auto& ks = _db.local().find_keyspace(keyspace);
+            auto rf = ks.get_replication_strategy().get_replication_factor();
+            // When a replacing node replaces a dead node with keyspace of RF
+            // 1, it is expected that replacing node could not find a peer node
+            // that contains data to stream from.
+            if (_reason == streaming::stream_reason::replace && rf == 1) {
+                logger.warn("Unable to find sufficient sources to stream range {} for keyspace {} with RF = 1 for replace operation", range_, keyspace);
+            } else {
+                throw std::runtime_error(format("unable to find sufficient sources for streaming range {} in keyspace {}", range_, keyspace));
+            }
         }
     }
 

dht/range_streamer.hh

@@ -146,7 +146,7 @@ private:
      *                      here, we always exclude ourselves.
      * @return
      */
-    static std::unordered_map<inet_address, dht::token_range_vector>
+    std::unordered_map<inet_address, dht::token_range_vector>
     get_range_fetch_map(const std::unordered_map<dht::token_range, std::vector<inet_address>>& ranges_with_sources,
                         const std::unordered_set<std::unique_ptr<i_source_filter>>& source_filters,
                         const sstring& keyspace);

digest_algorithm.hh

@@ -28,7 +28,8 @@ namespace query {
 enum class digest_algorithm : uint8_t {
     none = 0,  // digest not required
     MD5 = 1,
-    xxHash = 2,// default algorithm
+    legacy_xxHash_without_null_digest = 2,
+    xxHash = 3, // default algorithm
 };
 
 }

digester.hh

@@ -36,7 +36,7 @@ struct noop_hasher {
 };
 
 class digester final {
-    std::variant<noop_hasher, md5_hasher, xx_hasher> _impl;
+    std::variant<noop_hasher, md5_hasher, xx_hasher, legacy_xx_hasher_without_null_digest> _impl;
 
 public:
     explicit digester(digest_algorithm algo) {
@@ -47,6 +47,9 @@ public:
         case digest_algorithm::xxHash:
             _impl = xx_hasher();
             break;
+        case digest_algorithm::legacy_xxHash_without_null_digest:
+            _impl = legacy_xx_hasher_without_null_digest();
+            break;
         case digest_algorithm ::none:
             _impl = noop_hasher();
             break;

dist/common/scripts/node_exporter_install

@@ -42,6 +42,11 @@ if __name__ == '__main__':
     if node_exporter_p.exists() or (bindir_p() / 'prometheus-node_exporter').exists():
         if force:
             print('node_exporter already installed, reinstalling')
+            try:
+                node_exporter = systemd_unit('node-exporter.service')
+                node_exporter.stop()
+            except:
+                pass
         else:
             print('node_exporter already installed, you can use `--force` to force reinstallation')
             sys.exit(1)

dist/common/scripts/scylla-housekeeping

@@ -61,7 +61,15 @@ def sh_command(*args):
     return out
 
 def get_url(path):
-    return urllib.request.urlopen(path).read().decode('utf-8')
+    # If server returns any error, like 403, or 500 urllib.request throws exception, which is not serializable.
+    # When multiprocessing routines fail to serialize it, it throws ambiguous serialization exception
+    #   from get_json_from_url.
+    # In order to see legit error we catch it from the inside of process, covert to string and
+    #   pass it as part of return value
+    try:
+        return 0, urllib.request.urlopen(path).read().decode('utf-8')
+    except Exception as exc:
+        return 1, str(exc)
 
 def get_json_from_url(path):
     pool = mp.Pool(processes=1)
@@ -71,13 +79,16 @@ def get_json_from_url(path):
     # to enforce a wallclock timeout.
     result = pool.apply_async(get_url, args=(path,))
     try:
-        retval = result.get(timeout=5)
+        status, retval = result.get(timeout=5)
     except mp.TimeoutError as err:
         pool.terminate()
         pool.join()
         raise
+    if status == 1:
+        raise RuntimeError(f'Failed to get "{path}" due to the following error: {retval}')
     return json.loads(retval)
 
+
 def get_api(path):
     return get_json_from_url("http://" + api_address + path)
 

dist/common/scripts/scylla_coredump_setup

@@ -65,8 +65,8 @@ Before=scylla-server.service
 After=local-fs.target
 
 [Mount]
-What=/var/lib/systemd/coredump
-Where=/var/lib/scylla/coredump
+What=/var/lib/scylla/coredump
+Where=/var/lib/systemd/coredump
 Type=none
 Options=bind
 
@@ -78,6 +78,7 @@ WantedBy=multi-user.target
             makedirs('/var/lib/scylla/coredump')
             systemd_unit.reload()
             systemd_unit('var-lib-systemd-coredump.mount').enable()
+            systemd_unit('var-lib-systemd-coredump.mount').start()
         if os.path.exists('/usr/lib/sysctl.d/50-coredump.conf'):
             run('sysctl -p /usr/lib/sysctl.d/50-coredump.conf')
         else:
@@ -99,6 +100,14 @@ WantedBy=multi-user.target
         try:
             run('coredumpctl --no-pager --no-legend info {}'.format(pid))
             print('\nsystemd-coredump is working finely.')
+
+            # get last coredump generated by bash and remove it, ignore inaccessaible ones
+            corefile = out(cmd=r'coredumpctl -1 --no-legend dump 2>&1 | grep "bash" | '
+                               r'grep -v "inaccessible" | grep "Storage:\|Coredump:"',
+                           shell=True, exception=False)
+            if corefile:
+                corefile = corefile.split()[-1]
+                run('rm -f {}'.format(corefile))
         except subprocess.CalledProcessError as e:
             print('Does not able to detect coredump, failed to configure systemd-coredump.')
             sys.exit(1)

dist/common/scripts/scylla_setup

@@ -374,6 +374,9 @@ if __name__ == '__main__':
                 if not stat.S_ISBLK(os.stat(dsk).st_mode):
                     print('{} is not block device'.format(dsk))
                     continue
+                if dsk in selected:
+                    print(f'{dsk} is already added')
+                    continue
                 selected.append(dsk)
                 devices.remove(dsk)
             disks = ','.join(selected)

dist/common/scripts/scylla_util.py

@@ -96,7 +96,7 @@ def curl(url, byte=False):
                     return res.read()
                 else:
                     return res.read().decode('utf-8')
-        except urllib.error.HTTPError:
+        except urllib.error.URLError:
             logging.warn("Failed to grab %s..." % url)
             time.sleep(5)
             retries += 1
@@ -182,7 +182,7 @@ class aws_instance:
         instance_size = self.instance_size()
         if instance_class in ['c3', 'c4', 'd2', 'i2', 'r3']:
             return 'ixgbevf'
-        if instance_class in ['c5', 'c5d', 'f1', 'g3', 'h1', 'i3', 'i3en', 'm5', 'm5d', 'p2', 'p3', 'r4', 'x1']:
+        if instance_class in ['a1', 'c5', 'c5a', 'c5d', 'c5n', 'c6g', 'c6gd', 'f1', 'g3', 'g4', 'h1', 'i3', 'i3en', 'inf1', 'm5', 'm5a', 'm5ad', 'm5d', 'm5dn', 'm5n', 'm6g', 'm6gd', 'p2', 'p3', 'r4', 'r5', 'r5a', 'r5ad', 'r5d', 'r5dn', 'r5n', 't3', 't3a', 'u-6tb1', 'u-9tb1', 'u-12tb1', 'u-18tn1', 'u-24tb1', 'x1', 'x1e', 'z1d']:
             return 'ena'
         if instance_class == 'm4':
             if instance_size == '16xlarge':
@@ -219,7 +219,7 @@ class aws_instance:
 
     def ebs_disks(self):
         """Returns all EBS disks"""
-        return set(self._disks["ephemeral"])
+        return set(self._disks["ebs"])
 
     def public_ipv4(self):
         """Returns the public IPv4 address of this instance"""
@@ -327,9 +327,7 @@ class scylla_cpuinfo:
             return len(self._cpu_data["system"])
 
 
-# When a CLI tool is not installed, use relocatable CLI tool provided by Scylla
 scylla_env = os.environ.copy()
-scylla_env['PATH'] =  '{}:{}'.format(scylla_env['PATH'], scyllabindir())
 
 def run(cmd, shell=False, silent=False, exception=True):
     stdout = subprocess.DEVNULL if silent else None
@@ -441,6 +439,19 @@ def dist_ver():
     return platform.dist()[1]
 
 
+SYSTEM_PARTITION_UUIDS = [
+        '21686148-6449-6e6f-744e-656564454649', # BIOS boot partition
+        'c12a7328-f81f-11d2-ba4b-00a0c93ec93b', # EFI system partition
+        '024dee41-33e7-11d3-9d69-0008c781f39f'  # MBR partition scheme
+]
+
+def get_partition_uuid(dev):
+    return out(f'lsblk -n -oPARTTYPE {dev}')
+
+def is_system_partition(dev):
+    uuid = get_partition_uuid(dev)
+    return (uuid in SYSTEM_PARTITION_UUIDS)
+
 def is_unused_disk(dev):
     # dev is not in /sys/class/block/, like /dev/nvme[0-9]+
     if not os.path.isdir('/sys/class/block/{dev}'.format(dev=dev.replace('/dev/', ''))):
@@ -448,7 +459,8 @@ def is_unused_disk(dev):
     try:
         fd = os.open(dev, os.O_EXCL)
         os.close(fd)
-        return True
+        # dev is not reserved for system
+        return not is_system_partition(dev)
     except OSError:
         return False
 

dist/common/sysctl.d/99-scylla-inotify.conf

@@ -0,0 +1,4 @@
+# allocate enough inotify instances for large machines
+# each tls instance needs 1 inotify instance, and there can be
+# multiple tls instances per shard.
+fs.inotify.max_user_instances = 1200

dist/debian/control.mustache

@@ -5,6 +5,7 @@ Section: database
 Priority: optional
 X-Python3-Version: >= 3.4
 Standards-Version: 3.9.5
+Rules-Requires-Root: no
 
 Package: {{product}}-conf
 Architecture: any

dist/debian/debian/scylla-kernel-conf.postinst

@@ -11,6 +11,7 @@ else
     sysctl -p/usr/lib/sysctl.d/99-scylla-sched.conf || :
     sysctl -p/usr/lib/sysctl.d/99-scylla-aio.conf || :
     sysctl -p/usr/lib/sysctl.d/99-scylla-vm.conf || :
+    sysctl -p/usr/lib/sysctl.d/99-scylla-inotify.conf || :
 fi
 
 #DEBHELPER#

dist/debian/python3/control.mustache

@@ -5,6 +5,7 @@ Section: python
 Priority: optional
 X-Python3-Version: >= 3.4
 Standards-Version: 3.9.5
+Rules-Requires-Root: no
 
 Package: {{product}}-python3
 Architecture: amd64

dist/debian/rules.mustache

@@ -37,6 +37,7 @@ override_dh_strip:
 	# The binaries (ethtool...patchelf) don't pass dh_strip after going through patchelf. Since they are
 	# already stripped, nothing is lost if we exclude them, so that's what we do.
 	dh_strip -Xlibprotobuf.so.15 -Xld.so -Xethtool -Xgawk -Xgzip -Xhwloc-calc -Xhwloc-distrib -Xifconfig -Xlscpu -Xnetstat -Xpatchelf --dbg-package={{product}}-server-dbg
+	find $(CURDIR)/debian/{{product}}-server-dbg/usr/lib/debug/.build-id/ -name "*.debug" -exec objcopy --decompress-debug-sections {} \;
 
 override_dh_makeshlibs:
 

dist/docker/redhat/commandlineparser.py

@@ -18,6 +18,8 @@ def parse():
     parser.add_argument('--api-address', default=None, dest='apiAddress')
     parser.add_argument('--alternator-address', default=None, dest='alternatorAddress', help="Alternator API address to listen to. Defaults to listen address.")
     parser.add_argument('--alternator-port', default=None, dest='alternatorPort', help="Alternator API port to listen to. Disabled by default.")
+    parser.add_argument('--alternator-https-port', default=None, dest='alternatorHttpsPort', help="Alternator API TLS port to listen to. Disabled by default.")
+    parser.add_argument('--alternator-write-isolation', default=None, dest='alternatorWriteIsolation', help="Alternator default write isolation policy.")
     parser.add_argument('--disable-version-check', default=False, action='store_true', dest='disable_housekeeping', help="Disable version check")
     parser.add_argument('--authenticator', default=None, dest='authenticator', help="Set authenticator class")
     parser.add_argument('--authorizer', default=None, dest='authorizer', help="Set authorizer class")

dist/docker/redhat/scyllasetup.py

@@ -16,6 +16,8 @@ class ScyllaSetup:
         self._broadcastRpcAddress = arguments.broadcastRpcAddress
         self._apiAddress = arguments.apiAddress
         self._alternatorPort = arguments.alternatorPort
+        self._alternatorHttpsPort = arguments.alternatorHttpsPort
+        self._alternatorWriteIsolation = arguments.alternatorWriteIsolation
         self._smp = arguments.smp
         self._memory = arguments.memory
         self._overprovisioned = arguments.overprovisioned
@@ -116,6 +118,13 @@ class ScyllaSetup:
             args += ["--alternator-address %s" % self._alternatorAddress]
             args += ["--alternator-port %s" % self._alternatorPort]
 
+        if self._alternatorHttpsPort is not None:
+            args += ["--alternator-address %s" % self._alternatorAddress]
+            args += ["--alternator-https-port %s" % self._alternatorHttpsPort]
+
+        if self._alternatorWriteIsolation is not None:
+            args += ["--alternator-write-isolation %s" % self._alternatorWriteIsolation]
+
         if self._authenticator is not None:
             args += ["--authenticator %s" % self._authenticator]
 

dist/redhat/scylla.spec.mustache

@@ -130,10 +130,9 @@ rm -rf $RPM_BUILD_ROOT
 %attr(0755,scylla,scylla) %dir %{_sharedstatedir}/scylla-housekeeping
 %ghost /etc/systemd/system/scylla-helper.slice.d/
 %ghost /etc/systemd/system/scylla-helper.slice.d/memory.conf
-%ghost /etc/systemd/system/scylla-server.service.d/
 %ghost /etc/systemd/system/scylla-server.service.d/capabilities.conf
 %ghost /etc/systemd/system/scylla-server.service.d/mounts.conf
-%ghost /etc/systemd/system/scylla-server.service.d/dependencies.conf
+/etc/systemd/system/scylla-server.service.d/dependencies.conf
 %ghost /etc/systemd/system/var-lib-systemd-coredump.mount
 
 %package conf
@@ -189,6 +188,8 @@ Summary:        Scylla configuration package for the Linux kernel
 License:        AGPLv3
 URL:            http://www.scylladb.com/
 Requires:       kmod
+# tuned overwrites our sysctl settings
+Obsoletes:     tuned
 
 %description kernel-conf
 This package contains Linux kernel configuration changes for the Scylla database.  Install this package
@@ -200,6 +201,7 @@ if Scylla is the main application on your server and you wish to optimize its la
 /usr/lib/systemd/systemd-sysctl 99-scylla-sched.conf >/dev/null 2>&1 || :
 /usr/lib/systemd/systemd-sysctl 99-scylla-aio.conf >/dev/null 2>&1 || :
 /usr/lib/systemd/systemd-sysctl 99-scylla-vm.conf >/dev/null 2>&1 || :
+/usr/lib/systemd/systemd-sysctl 99-scylla-inotify.conf >/dev/null 2>&1 || :
 
 %files kernel-conf
 %defattr(-,root,root)

docs/alternator/alternator.md

@@ -25,6 +25,14 @@ By default, Scylla listens on this port on all network interfaces.
 To listen only on a specific interface, pass also an "`alternator-address`"
 option.
 
+As we explain below in the "Write isolation policies", Alternator has
+four different choices for the implementation of writes, each with
+different advantages. You should consider which of the options makes
+more sense for your intended use case, and use the "`--alternator-write-isolation`"
+option to choose one. There is currently no default for this option: Trying
+to run Scylla with Alternator enabled without passing this option will
+result in an error asking you to set it.
+
 DynamoDB clients usually specify a single "endpoint" address, e.g.,
 `dynamodb.us-east-1.amazonaws.com`, and a DNS server hosted on that address
 distributes the connections to many different backend nodes. Alternator
@@ -108,12 +116,15 @@ implemented, with the following limitations:
   Writes are done in LOCAL_QURUM and reads in LOCAL_ONE (eventual consistency)
   or LOCAL_QUORUM (strong consistency).
 ### Global Tables
-* Currently, *all* Alternator tables are created as "Global Tables", i.e., can
-  be accessed from all of Scylla's DCs.
-* We do not yet support the DynamoDB API calls to make some of the tables
-  global and others local to a particular DC: CreateGlobalTable,
-  UpdateGlobalTable, DescribeGlobalTable, ListGlobalTables,
-  UpdateGlobalTableSettings, DescribeGlobalTableSettings, and UpdateTable.
+* Currently, *all* Alternator tables are created as "global" tables and can
+  be accessed from all the DCs existing at the time of the table's creation.
+  If a DC is added after a table is created, the table won't be visible from
+  the new DC and changing that requires a CQL "ALTER TABLE" statement to
+  modify the table's replication strategy.
+* We do not yet support the DynamoDB API calls that control which table is
+  visible from what DC: CreateGlobalTable, UpdateGlobalTable,
+  DescribeGlobalTable, ListGlobalTables, UpdateGlobalTableSettings,
+  DescribeGlobalTableSettings, and UpdateTable.
 ### Backup and Restore
 * On-demand backup: the DynamoDB APIs are not yet supported: CreateBackup,
   DescribeBackup, DeleteBackup, ListBackups, RestoreTableFromBackup.
@@ -153,23 +164,28 @@ implemented, with the following limitations:
 
 ### Write isolation policies
 DynamoDB API update requests may involve a read before the write - e.g., a
-_conditional_ update, or an update based on the old value of an attribute.
+_conditional_ update or an update based on the old value of an attribute.
 The read and the write should be treated as a single transaction - protected
 (_isolated_) from other parallel writes to the same item.
 
-By default, Alternator does this isolation by using Scylla's LWT (lightweight
-transactions) for every write operation. However, LWT significantly slows
-writes down, so Alternator supports three additional _write isolation
-policies_, which can be chosen on a per-table basis and may make sense for
-certain workloads as explained below.
+Alternator could do this isolation by using Scylla's LWT (lightweight
+transactions) for every write operation, but this significantly slows
+down writes, and not necessary for workloads which don't use read-modify-write
+(RMW) updates.
 
-The write isolation policy of a table is configured by tagging the table (at
-CreateTable time, or any time later with TagResource) with the key
+So Alternator supports four _write isolation policies_, which can be chosen
+on a per-table basis and may make sense for certain workloads as explained
+below.
+
+A default write isolation policy **must** be chosen using the
+`--alternator-write-isolation` configuration option. Additionally, the write
+isolation policy for a specific table can be overriden by tagging the table
+(at CreateTable time, or any time later with TagResource) with the key
 `system:write_isolation`, and one of the following values:
 
-  * `a`, `always`, or `always_use_lwt` - This is the default choice.
-    It performs every write operation - even those that do not need a read
-    before the write - as a lightweight transaction.
+  * `a`, `always`, or `always_use_lwt` - This mode performs every write
+    operation - even those that do not need a read before the write - as a
+    lightweight transaction.
 
     This is the slowest choice, but also the only choice guaranteed to work
     correctly for every workload.

docs/alternator/getting-started.md

@@ -10,10 +10,16 @@ This section will guide you through the steps for setting up the cluster:
    nightly image by running: `docker pull scylladb/scylla-nightly:latest`
 2. Follow the steps in the [Scylla official download web page](https://www.scylladb.com/download/open-source/#docker)
    add to every "docker run" command: `-p 8000:8000` before the image name
-   and `--alternator-port=8000` at the end. The "alternator-port" option
-   specifies on which port Scylla will listen for the (unencrypted) DynamoDB API.
+   and `--alternator-port=8000 --alternator-write-isolation=always` at the end.
+   The "alternator-port" option specifies on which port Scylla will listen for
+   the (unencrypted) DynamoDB API, and the "alternator-write-isolation" chooses
+   whether or not Alternator will use LWT for every write.
    For example,
-   `docker run --name scylla -d -p 8000:8000 scylladb/scylla-nightly:latest --alternator-port=8000
+   `docker run --name scylla -d -p 8000:8000 scylladb/scylla-nightly:latest --alternator-port=8000 --alternator-write-isolation=always
+   The `--alternator-https-port=...` option can also be used to enable
+   Alternator on an encrypted (HTTPS) port. Note that in this case, the files
+   `/etc/scylla/scylla.crt` and `/etc/scylla/scylla.key` must be inserted into
+   the image, containing the SSL certificate and key to use.
 
 ## Testing Scylla's DynamoDB API support:
 ### Running AWS Tic Tac Toe demo app to test the cluster:

docs/cdc.md

@@ -92,7 +92,7 @@ Shard-colocation is an optimization.
 
 Having different generations operating at different points in time is necessary to maintain colocation in presence of topology changes. When a new node joins the cluster it modifies the token ring by refining existing vnodes into smaller vnodes. But before it does it, it will introduce a new CDC generation whose token ranges refine those new (smaller) vnodes (which means they also refine the old vnodes; that way writes will be colocated on both old and new replicas).
 
-The joining node learns about the current vnodes, chooses tokens which will split them into smaller vnodes and creates a new `cdc::topology_description` which refines those smaller vnodes. This is done in the `cdc::generate_topology_description` function. It then inserts the generation description into an internal distributed table `cdc_topology_description` in the `system_distributed` keyspace. The table is defined as follows (from db/system_distributed_keyspace.cc):
+The joining node learns about the current vnodes, chooses tokens which will split them into smaller vnodes and creates a new `cdc::topology_description` which refines those smaller vnodes. This is done in the `cdc::generate_topology_description` function. It then inserts the generation description into an internal distributed table `cdc_generations` in the `system_distributed` keyspace. The table is defined as follows (from db/system_distributed_keyspace.cc):
 ```
         return schema_builder(system_distributed_keyspace::NAME, system_distributed_keyspace::CDC_TOPOLOGY_DESCRIPTION, {id})
                 /* The timestamp of this CDC generation. */
@@ -131,11 +131,11 @@ Next, the node starts gossiping the timestamp of the new generation together wit
         }).get();
 ```
 
-When other nodes learn about the generation, they'll extract it from the `cdc_topology_description` table and save it using `cdc::metadata::insert(db_clock::time_point, topology_description&&)`.
+When other nodes learn about the generation, they'll extract it from the `cdc_generations` table and save it using `cdc::metadata::insert(db_clock::time_point, topology_description&&)`.
 Notice that nodes learn about the generation together with the new node's tokens. When they learn about its tokens they'll immediately start sending writes to the new node (in the case of bootstrapping, it will become a pending replica). But the old generation will still be operating for a minute or two. Thus colocation will be lost for a while. This problem will be fixed when the two-phase-commit approach is implemented.
 
 We're not able to prevent a node learning about a new generation too late due to a network partition: if gossip doesn't reach the node in time, some writes might be sent to the wrong (old) generation.
-However, it could happen that a node learns about the generation from gossip in time, but then won't be able to extract it from `cdc_topology_description`. In that case we can still maintain consistency: the node will remember that there is a new generation even though it doesn't yet know what it is (just the timestamp) using the `cdc::metadata::prepare(db_clock::time_point)` method, and then _reject_ writes for CDC-enabled tables that are supposed to use this new generation. The node will keep trying to read the generation's data in background until it succeeds or sees that it's not necessary anymore (e.g. because the generation was already superseded by a new generation).
+However, it could happen that a node learns about the generation from gossip in time, but then won't be able to extract it from `cdc_generations`. In that case we can still maintain consistency: the node will remember that there is a new generation even though it doesn't yet know what it is (just the timestamp) using the `cdc::metadata::prepare(db_clock::time_point)` method, and then _reject_ writes for CDC-enabled tables that are supposed to use this new generation. The node will keep trying to read the generation's data in background until it succeeds or sees that it's not necessary anymore (e.g. because the generation was already superseded by a new generation).
 Thus we give up availability for safety. This likely won't happen if the administrator ensures that the cluster is not partitioned before bootstrapping a new node. This problem will also be mitigated with a future patch.
 
 Due to the need of maintaining colocation we don't allow the client to send writes with arbitrary timestamps.
@@ -144,7 +144,7 @@ Reason: we cannot allow writes before `T`, because they belong to the old genera
 
 ### Streams description table
 
-The `cdc_description` table in the `system_distributed` keyspace allows CDC clients to learn about available sets of streams and the time intervals they are operating at. It's definition is as follows (db/system_distributed_keyspace.cc):
+The `cdc_streams` table in the `system_distributed` keyspace allows CDC clients to learn about available sets of streams and the time intervals they are operating at. It's definition is as follows (db/system_distributed_keyspace.cc):
 ```
         return schema_builder(system_distributed_keyspace::NAME, system_distributed_keyspace::CDC_DESC, {id})
                 /* The timestamp of this CDC generation. */
@@ -161,9 +161,9 @@ where
 thread_local data_type cdc_stream_tuple_type = tuple_type_impl::get_instance({long_type, long_type});
 thread_local data_type cdc_streams_set_type = set_type_impl::get_instance(cdc_stream_tuple_type, false);
 ```
-This table simply contains each generation's timestamp (as partition key) and the set of stream IDs used by this generation. It is meant to be user-facing, in contrast to `cdc_topology_description` which is used internally.
+This table simply contains each generation's timestamp (as partition key) and the set of stream IDs used by this generation. It is meant to be user-facing, in contrast to `cdc_generations` which is used internally.
 
 When nodes learn about a CDC generation through gossip, they race to update the description table by inserting a proper row (see `cdc::update_streams_description`). This operation is idempotent so it doesn't matter if multiple nodes do it at the same time.
 
 #### TODO: expired generations
-The `expired` column in `cdc_description` and `cdc_topology_description` means that this generation was superseded by some new generation and will soon be removed (its table entry will be gone). This functionality is yet to be implemented.
+The `expired` column in `cdc_streams` and `cdc_generations` means that this generation was superseded by some new generation and will soon be removed (its table entry will be gone). This functionality is yet to be implemented.

docs/docker-hub.md

@@ -163,6 +163,20 @@ $ docker run --name some-scylla -d scylladb/scylla --alternator-port 8000
 
 **Since: 3.2**
 
+### `--alternator-https-port PORT`
+
+The `--alternator-https-port` option is similar to `--alternator-port`, just enables an encrypted (HTTPS) port. Either the `--alternator-https-port` or `--alternator-http-port`, or both, can be used to enable Alternator.
+
+Note that the `--alternator-https-port` option also requires that files `/etc/scylla/scylla.crt` and `/etc/scylla/scylla.key` be inserted into the image. These files contain an SSL certificate and key, respectively.
+
+**Since: 4.2**
+
+### `--alternator-write-isolation policy`
+
+The `--alternator-write-isolation` command line option chooses between four allowed write isolation policies described in docs/alternator/alternator.md. This option must be specified if Alternator is enabled - it does not have a default.
+
+**Since: 4.1**
+
 ### `--broadcast-address ADDR`
 
 The `--broadcast-address` command line option configures the IP address the Scylla instance tells other Scylla nodes in the cluster to connect to.

flat_mutation_reader.hh

@@ -488,6 +488,9 @@ public:
     size_t buffer_size() const {
         return _impl->buffer_size();
     }
+    const circular_buffer<mutation_fragment>& buffer() const {
+        return _impl->buffer();
+    }
     // Detach the internal buffer of the reader.
     // Roughly equivalent to depleting it by calling pop_mutation_fragment()
     // until is_buffer_empty() returns true.

gms/feature.hh

@@ -140,6 +140,7 @@ extern const std::string_view NONFROZEN_UDTS;
 extern const std::string_view HINTED_HANDOFF_SEPARATE_CONNECTION;
 extern const std::string_view LWT;
 extern const std::string_view PER_TABLE_PARTITIONERS;
+extern const std::string_view DIGEST_FOR_NULL_VALUES;
 
 }
 

gms/feature_service.cc

@@ -55,6 +55,7 @@ constexpr std::string_view features::NONFROZEN_UDTS = "NONFROZEN_UDTS";
 constexpr std::string_view features::HINTED_HANDOFF_SEPARATE_CONNECTION = "HINTED_HANDOFF_SEPARATE_CONNECTION";
 constexpr std::string_view features::LWT = "LWT";
 constexpr std::string_view features::PER_TABLE_PARTITIONERS = "PER_TABLE_PARTITIONERS";
+constexpr std::string_view features::DIGEST_FOR_NULL_VALUES = "DIGEST_FOR_NULL_VALUES";
 
 static logging::logger logger("features");
 
@@ -88,8 +89,9 @@ feature_service::feature_service(feature_config cfg) : _config(cfg)
         , _nonfrozen_udts(*this, features::NONFROZEN_UDTS)
         , _hinted_handoff_separate_connection(*this, features::HINTED_HANDOFF_SEPARATE_CONNECTION)
         , _lwt_feature(*this, features::LWT)
-        , _per_table_partitioners_feature(*this, features::PER_TABLE_PARTITIONERS) {
-}
+        , _per_table_partitioners_feature(*this, features::PER_TABLE_PARTITIONERS)
+        , _digest_for_null_values_feature(*this, features::DIGEST_FOR_NULL_VALUES)
+{}
 
 feature_config feature_config_from_db_config(db::config& cfg) {
     feature_config fcfg;
@@ -163,6 +165,7 @@ std::set<std::string_view> feature_service::known_feature_set() {
         gms::features::UNBOUNDED_RANGE_TOMBSTONES,
         gms::features::HINTED_HANDOFF_SEPARATE_CONNECTION,
         gms::features::PER_TABLE_PARTITIONERS,
+        gms::features::DIGEST_FOR_NULL_VALUES,
     };
 
     if (_config.enable_sstables_mc_format) {
@@ -254,6 +257,7 @@ void feature_service::enable(const std::set<std::string_view>& list) {
         std::ref(_hinted_handoff_separate_connection),
         std::ref(_lwt_feature),
         std::ref(_per_table_partitioners_feature),
+        std::ref(_digest_for_null_values_feature),
     })
     {
         if (list.count(f.name())) {

gms/feature_service.hh

@@ -96,6 +96,7 @@ private:
     gms::feature _hinted_handoff_separate_connection;
     gms::feature _lwt_feature;
     gms::feature _per_table_partitioners_feature;
+    gms::feature _digest_for_null_values_feature;
 
 public:
     bool cluster_supports_range_tombstones() const {
@@ -166,6 +167,10 @@ public:
         return _per_table_partitioners_feature;
     }
 
+    const feature& cluster_supports_digest_for_null_values() const {
+        return _digest_for_null_values_feature;
+    }
+
     bool cluster_supports_row_level_repair() const {
         return bool(_row_level_repair_feature);
     }

gms/gossiper.cc

@@ -428,6 +428,7 @@ future<> gossiper::handle_shutdown_msg(inet_address from) {
         return make_ready_future<>();
     }
     return seastar::async([this, from] {
+        auto permit = this->lock_endpoint(from).get0();
         this->mark_as_shutdown(from);
     });
 }

gms/gossiper.hh

@@ -175,6 +175,7 @@ public:
         versioned_value::STATUS_LEFT,
         versioned_value::HIBERNATE,
         versioned_value::STATUS_BOOTSTRAPPING,
+        versioned_value::STATUS_UNKNOWN,
     };
     static constexpr std::chrono::milliseconds INTERVAL{1000};
     static constexpr std::chrono::hours A_VERY_LONG_TIME{24 * 3};

idl/streaming.idl.hh

@@ -49,6 +49,7 @@ enum class stream_reason : uint8_t {
     removenode,
     rebuild,
     repair,
+    replace,
 };
 
 enum class stream_mutation_fragments_cmd : uint8_t {

install.sh

@@ -132,6 +132,7 @@ relocate_python3() {
     cp "$script" "$relocateddir"
     cat > "$install"<<EOF
 #!/usr/bin/env bash
+export LC_ALL=en_US.UTF-8
 x="\$(readlink -f "\$0")"
 b="\$(basename "\$x")"
 d="\$(dirname "\$x")"
@@ -143,7 +144,7 @@ DEBIAN_SSL_CERT_FILE="/etc/ssl/certs/ca-certificates.crt"
 if [ -f "\${DEBIAN_SSL_CERT_FILE}" ]; then
   c=\${DEBIAN_SSL_CERT_FILE}
 fi
-PYTHONPATH="\${d}:\${d}/libexec:\$PYTHONPATH" PATH="\${d}/$pythonpath:\${PATH}" SSL_CERT_FILE="\${c}" exec -a "\$0" "\${d}/libexec/\${b}" "\$@"
+PYTHONPATH="\${d}:\${d}/libexec:\$PYTHONPATH" PATH="\${d}/../bin:\${d}/$pythonpath:\${PATH}" SSL_CERT_FILE="\${c}" exec -a "\$0" "\${d}/libexec/\${b}" "\$@"
 EOF
     chmod +x "$install"
 }
@@ -378,5 +379,9 @@ elif ! $packaging; then
     chown -R scylla:scylla $rdata
     chown -R scylla:scylla $rhkdata
 
+    for file in dist/common/sysctl.d/*.conf; do
+        bn=$(basename "$file")
+        sysctl -p "$rusr"/lib/sysctl.d/"$bn"
+    done
     $rprefix/scripts/scylla_post_install.sh
 fi

licenses/abseil-license.txt

@@ -0,0 +1,203 @@
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+
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+
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locator/abstract_replication_strategy.cc

@@ -168,15 +168,33 @@ insert_token_range_to_sorted_container_while_unwrapping(
 
 dht::token_range_vector
 abstract_replication_strategy::get_ranges(inet_address ep) const {
-    return get_ranges(ep, _token_metadata);
+    return do_get_ranges(ep, _token_metadata, false);
+}
+
+dht::token_range_vector
+abstract_replication_strategy::get_ranges_in_thread(inet_address ep) const {
+    return do_get_ranges(ep, _token_metadata, true);
 }
 
 dht::token_range_vector
 abstract_replication_strategy::get_ranges(inet_address ep, token_metadata& tm) const {
+    return do_get_ranges(ep, tm, false);
+}
+
+dht::token_range_vector
+abstract_replication_strategy::get_ranges_in_thread(inet_address ep, token_metadata& tm) const {
+    return do_get_ranges(ep, tm, true);
+}
+
+dht::token_range_vector
+abstract_replication_strategy::do_get_ranges(inet_address ep, token_metadata& tm, bool can_yield) const {
     dht::token_range_vector ret;
     auto prev_tok = tm.sorted_tokens().back();
     for (auto tok : tm.sorted_tokens()) {
         for (inet_address a : calculate_natural_endpoints(tok, tm)) {
+            if (can_yield) {
+                seastar::thread::maybe_yield();
+            }
             if (a == ep) {
                 insert_token_range_to_sorted_container_while_unwrapping(prev_tok, tok, ret);
                 break;

locator/abstract_replication_strategy.hh

@@ -113,10 +113,15 @@ public:
     // It the analogue of Origin's getAddressRanges().get(endpoint).
     // This function is not efficient, and not meant for the fast path.
     dht::token_range_vector get_ranges(inet_address ep) const;
+    dht::token_range_vector get_ranges_in_thread(inet_address ep) const;
 
     // Use the token_metadata provided by the caller instead of _token_metadata
     dht::token_range_vector get_ranges(inet_address ep, token_metadata& tm) const;
+    dht::token_range_vector get_ranges_in_thread(inet_address ep, token_metadata& tm) const;
+private:
+    dht::token_range_vector do_get_ranges(inet_address ep, token_metadata& tm, bool can_yield) const;
 
+public:
     // get_primary_ranges() returns the list of "primary ranges" for the given
     // endpoint. "Primary ranges" are the ranges that the node is responsible
     // for storing replica primarily, which means this is the first node

locator/token_metadata.cc

@@ -1975,9 +1975,7 @@ void topology::add_endpoint(const inet_address& ep)
         if (current->second.dc == dc && current->second.rack == rack) {
             return;
         }
-
-        _dc_racks[current->second.dc][current->second.rack].erase(ep);
-        _dc_endpoints[current->second.dc].erase(ep);
+        remove_endpoint(ep);
     }
 
     _dc_endpoints[dc].insert(ep);
@@ -2002,7 +2000,14 @@ void topology::remove_endpoint(inet_address ep)
     }
 
     _dc_endpoints[cur_dc_rack->second.dc].erase(ep);
-    _dc_racks[cur_dc_rack->second.dc][cur_dc_rack->second.rack].erase(ep);
+
+    auto& racks = _dc_racks[cur_dc_rack->second.dc];
+    auto& eps = racks[cur_dc_rack->second.rack];
+    eps.erase(ep);
+    if (eps.empty()) {
+        racks.erase(cur_dc_rack->second.rack);
+    }
+
     _current_locations.erase(cur_dc_rack);
 }
 

lua.cc

@@ -264,14 +264,12 @@ static auto visit_lua_raw_value(lua_State* l, int index, Func&& f) {
 
 template <typename Func>
 static auto visit_decimal(const big_decimal &v, Func&& f) {
-    boost::multiprecision::cpp_int ten(10);
-    const auto& dividend = v.unscaled_value();
-    auto divisor = boost::multiprecision::pow(ten, v.scale());
+    boost::multiprecision::cpp_rational r = v.as_rational();
+    const boost::multiprecision::cpp_int& dividend = numerator(r);
+    const boost::multiprecision::cpp_int& divisor = denominator(r);
     if (dividend % divisor == 0) {
-        return f(utils::multiprecision_int(boost::multiprecision::cpp_int(dividend/divisor)));
+        return f(utils::multiprecision_int(dividend/divisor));
     }
-    boost::multiprecision::cpp_rational r = dividend;
-    r /= divisor;
     return f(r.convert_to<double>());
 }
 

main.cc

@@ -78,6 +78,7 @@
 #include "cdc/log.hh"
 #include "cdc/cdc_extension.hh"
 #include "alternator/tags_extension.hh"
+#include "alternator/rmw_operation.hh"
 
 namespace fs = std::filesystem;
 
@@ -736,7 +737,7 @@ int main(int ac, char** av) {
             dbcfg.memtable_scheduling_group = make_sched_group("memtable", 1000);
             dbcfg.memtable_to_cache_scheduling_group = make_sched_group("memtable_to_cache", 200);
             dbcfg.available_memory = memory::stats().total_memory();
-            db.start(std::ref(*cfg), dbcfg, std::ref(mm_notifier), std::ref(feature_service), std::ref(token_metadata), std::ref(stop_signal.as_sharded_abort_source())).get();
+            db.start(std::ref(*cfg), dbcfg, std::ref(mm_notifier), std::ref(feature_service), std::ref(token_metadata)).get();
             start_large_data_handler(db).get();
             auto stop_database_and_sstables = defer_verbose_shutdown("database", [&db] {
                 // #293 - do not stop anything - not even db (for real)
@@ -820,6 +821,7 @@ int main(int ac, char** av) {
             storage_proxy_smp_service_group_config.max_nonlocal_requests = 5000;
             spcfg.read_smp_service_group = create_smp_service_group(storage_proxy_smp_service_group_config).get0();
             spcfg.write_smp_service_group = create_smp_service_group(storage_proxy_smp_service_group_config).get0();
+            spcfg.hints_write_smp_service_group = create_smp_service_group(storage_proxy_smp_service_group_config).get0();
             spcfg.write_ack_smp_service_group = create_smp_service_group(storage_proxy_smp_service_group_config).get0();
             static db::view::node_update_backlog node_backlog(smp::count, 10ms);
             scheduling_group_key_config storage_proxy_stats_cfg =
@@ -948,12 +950,16 @@ int main(int ac, char** av) {
                 mm.init_messaging_service();
             }).get();
             supervisor::notify("initializing storage proxy RPC verbs");
-            proxy.invoke_on_all([] (service::storage_proxy& p) {
-                p.init_messaging_service();
-            }).get();
+            proxy.invoke_on_all(&service::storage_proxy::init_messaging_service).get();
+            auto stop_proxy_handlers = defer_verbose_shutdown("storage proxy RPC verbs", [&proxy] {
+                proxy.invoke_on_all(&service::storage_proxy::uninit_messaging_service).get();
+            });
 
             supervisor::notify("starting streaming service");
             streaming::stream_session::init_streaming_service(db, sys_dist_ks, view_update_generator).get();
+            auto stop_streaming_service = defer_verbose_shutdown("streaming service", [] {
+                streaming::stream_session::uninit_streaming_service().get();
+            });
             api::set_server_stream_manager(ctx).get();
 
             supervisor::notify("starting hinted handoff manager");
@@ -986,6 +992,9 @@ int main(int ac, char** av) {
                 rs.stop().get();
             });
             repair_init_messaging_service_handler(rs, sys_dist_ks, view_update_generator).get();
+            auto stop_repair_messages = defer_verbose_shutdown("repair message handlers", [] {
+                repair_uninit_messaging_service_handler().get();
+            });
             supervisor::notify("starting storage service", true);
             auto& ss = service::get_local_storage_service();
             ss.init_messaging_service_part().get();
@@ -1081,6 +1090,7 @@ int main(int ac, char** av) {
             }
 
             if (cfg->alternator_port() || cfg->alternator_https_port()) {
+                alternator::rmw_operation::set_default_write_isolation(cfg->alternator_write_isolation());
                 static sharded<alternator::executor> alternator_executor;
                 static sharded<alternator::server> alternator_server;
 
@@ -1186,6 +1196,12 @@ int main(int ac, char** av) {
                 }
             });
 
+            auto stop_compaction_manager = defer_verbose_shutdown("compaction manager", [&db] {
+                db.invoke_on_all([](auto& db) {
+                    return db.get_compaction_manager().stop();
+                }).get();
+            });
+
             auto stop_redis_service = defer_verbose_shutdown("redis service", [&cfg] {
                 if (cfg->redis_port() || cfg->redis_ssl_port()) {
                     redis.stop().get();

message/messaging_service.cc

@@ -731,6 +731,10 @@ void messaging_service::register_stream_mutation_fragments(std::function<future<
     register_handler(this, messaging_verb::STREAM_MUTATION_FRAGMENTS, std::move(func));
 }
 
+future<> messaging_service::unregister_stream_mutation_fragments() {
+    return unregister_handler(messaging_verb::STREAM_MUTATION_FRAGMENTS);
+}
+
 template<class SinkType, class SourceType>
 future<rpc::sink<SinkType>, rpc::source<SourceType>>
 do_make_sink_source(messaging_verb verb, uint32_t repair_meta_id, shared_ptr<messaging_service::rpc_protocol_client_wrapper> rpc_client, std::unique_ptr<messaging_service::rpc_protocol_wrapper>& rpc) {
@@ -762,6 +766,9 @@ rpc::sink<repair_row_on_wire_with_cmd> messaging_service::make_sink_for_repair_g
 void messaging_service::register_repair_get_row_diff_with_rpc_stream(std::function<future<rpc::sink<repair_row_on_wire_with_cmd>> (const rpc::client_info& cinfo, uint32_t repair_meta_id, rpc::source<repair_hash_with_cmd> source)>&& func) {
     register_handler(this, messaging_verb::REPAIR_GET_ROW_DIFF_WITH_RPC_STREAM, std::move(func));
 }
+future<> messaging_service::unregister_repair_get_row_diff_with_rpc_stream() {
+    return unregister_handler(messaging_verb::REPAIR_GET_ROW_DIFF_WITH_RPC_STREAM);
+}
 
 // Wrapper for REPAIR_PUT_ROW_DIFF_WITH_RPC_STREAM
 future<rpc::sink<repair_row_on_wire_with_cmd>, rpc::source<repair_stream_cmd>>
@@ -781,6 +788,9 @@ rpc::sink<repair_stream_cmd> messaging_service::make_sink_for_repair_put_row_dif
 void messaging_service::register_repair_put_row_diff_with_rpc_stream(std::function<future<rpc::sink<repair_stream_cmd>> (const rpc::client_info& cinfo, uint32_t repair_meta_id, rpc::source<repair_row_on_wire_with_cmd> source)>&& func) {
     register_handler(this, messaging_verb::REPAIR_PUT_ROW_DIFF_WITH_RPC_STREAM, std::move(func));
 }
+future<> messaging_service::unregister_repair_put_row_diff_with_rpc_stream() {
+    return unregister_handler(messaging_verb::REPAIR_PUT_ROW_DIFF_WITH_RPC_STREAM);
+}
 
 // Wrapper for REPAIR_GET_FULL_ROW_HASHES_WITH_RPC_STREAM
 future<rpc::sink<repair_stream_cmd>, rpc::source<repair_hash_with_cmd>>
@@ -800,6 +810,9 @@ rpc::sink<repair_hash_with_cmd> messaging_service::make_sink_for_repair_get_full
 void messaging_service::register_repair_get_full_row_hashes_with_rpc_stream(std::function<future<rpc::sink<repair_hash_with_cmd>> (const rpc::client_info& cinfo, uint32_t repair_meta_id, rpc::source<repair_stream_cmd> source)>&& func) {
     register_handler(this, messaging_verb::REPAIR_GET_FULL_ROW_HASHES_WITH_RPC_STREAM, std::move(func));
 }
+future<> messaging_service::unregister_repair_get_full_row_hashes_with_rpc_stream() {
+    return unregister_handler(messaging_verb::REPAIR_GET_FULL_ROW_HASHES_WITH_RPC_STREAM);
+}
 
 // Send a message for verb
 template <typename MsgIn, typename... MsgOut>
@@ -883,6 +896,9 @@ future<streaming::prepare_message> messaging_service::send_prepare_message(msg_a
     return send_message<streaming::prepare_message>(this, messaging_verb::PREPARE_MESSAGE, id,
         std::move(msg), plan_id, std::move(description), reason);
 }
+future<> messaging_service::unregister_prepare_message() {
+    return unregister_handler(messaging_verb::PREPARE_MESSAGE);
+}
 
 // PREPARE_DONE_MESSAGE
 void messaging_service::register_prepare_done_message(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, unsigned dst_cpu_id)>&& func) {
@@ -892,6 +908,9 @@ future<> messaging_service::send_prepare_done_message(msg_addr id, UUID plan_id,
     return send_message<void>(this, messaging_verb::PREPARE_DONE_MESSAGE, id,
         plan_id, dst_cpu_id);
 }
+future<> messaging_service::unregister_prepare_done_message() {
+    return unregister_handler(messaging_verb::PREPARE_DONE_MESSAGE);
+}
 
 // STREAM_MUTATION
 void messaging_service::register_stream_mutation(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, frozen_mutation fm, unsigned dst_cpu_id, rpc::optional<bool> fragmented, rpc::optional<streaming::stream_reason> reason)>&& func) {
@@ -916,6 +935,9 @@ future<> messaging_service::send_stream_mutation_done(msg_addr id, UUID plan_id,
     return send_message<void>(this, messaging_verb::STREAM_MUTATION_DONE, id,
         plan_id, std::move(ranges), cf_id, dst_cpu_id);
 }
+future<> messaging_service::unregister_stream_mutation_done() {
+    return unregister_handler(messaging_verb::STREAM_MUTATION_DONE);
+}
 
 // COMPLETE_MESSAGE
 void messaging_service::register_complete_message(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, unsigned dst_cpu_id, rpc::optional<bool> failed)>&& func) {
@@ -925,6 +947,9 @@ future<> messaging_service::send_complete_message(msg_addr id, UUID plan_id, uns
     return send_message<void>(this, messaging_verb::COMPLETE_MESSAGE, id,
         plan_id, dst_cpu_id, failed);
 }
+future<> messaging_service::unregister_complete_message() {
+    return unregister_handler(messaging_verb::COMPLETE_MESSAGE);
+}
 
 void messaging_service::register_gossip_echo(std::function<future<> ()>&& func) {
     register_handler(this, messaging_verb::GOSSIP_ECHO, std::move(func));
@@ -1139,14 +1164,14 @@ future<partition_checksum> messaging_service::send_repair_checksum_range(
 }
 
 // Wrapper for REPAIR_GET_FULL_ROW_HASHES
-void messaging_service::register_repair_get_full_row_hashes(std::function<future<std::unordered_set<repair_hash>> (const rpc::client_info& cinfo, uint32_t repair_meta_id)>&& func) {
+void messaging_service::register_repair_get_full_row_hashes(std::function<future<repair_hash_set> (const rpc::client_info& cinfo, uint32_t repair_meta_id)>&& func) {
     register_handler(this, messaging_verb::REPAIR_GET_FULL_ROW_HASHES, std::move(func));
 }
 future<> messaging_service::unregister_repair_get_full_row_hashes() {
     return unregister_handler(messaging_verb::REPAIR_GET_FULL_ROW_HASHES);
 }
-future<std::unordered_set<repair_hash>> messaging_service::send_repair_get_full_row_hashes(msg_addr id, uint32_t repair_meta_id) {
-    return send_message<future<std::unordered_set<repair_hash>>>(this, messaging_verb::REPAIR_GET_FULL_ROW_HASHES, std::move(id), repair_meta_id);
+future<repair_hash_set> messaging_service::send_repair_get_full_row_hashes(msg_addr id, uint32_t repair_meta_id) {
+    return send_message<future<repair_hash_set>>(this, messaging_verb::REPAIR_GET_FULL_ROW_HASHES, std::move(id), repair_meta_id);
 }
 
 // Wrapper for REPAIR_GET_COMBINED_ROW_HASH
@@ -1171,13 +1196,13 @@ future<get_sync_boundary_response> messaging_service::send_repair_get_sync_bound
 }
 
 // Wrapper for REPAIR_GET_ROW_DIFF
-void messaging_service::register_repair_get_row_diff(std::function<future<repair_rows_on_wire> (const rpc::client_info& cinfo, uint32_t repair_meta_id, std::unordered_set<repair_hash> set_diff, bool needs_all_rows)>&& func) {
+void messaging_service::register_repair_get_row_diff(std::function<future<repair_rows_on_wire> (const rpc::client_info& cinfo, uint32_t repair_meta_id, repair_hash_set set_diff, bool needs_all_rows)>&& func) {
     register_handler(this, messaging_verb::REPAIR_GET_ROW_DIFF, std::move(func));
 }
 future<> messaging_service::unregister_repair_get_row_diff() {
     return unregister_handler(messaging_verb::REPAIR_GET_ROW_DIFF);
 }
-future<repair_rows_on_wire> messaging_service::send_repair_get_row_diff(msg_addr id, uint32_t repair_meta_id, std::unordered_set<repair_hash> set_diff, bool needs_all_rows) {
+future<repair_rows_on_wire> messaging_service::send_repair_get_row_diff(msg_addr id, uint32_t repair_meta_id, repair_hash_set set_diff, bool needs_all_rows) {
     return send_message<future<repair_rows_on_wire>>(this, messaging_verb::REPAIR_GET_ROW_DIFF, std::move(id), repair_meta_id, std::move(set_diff), needs_all_rows);
 }
 

message/messaging_service.hh

@@ -276,10 +276,12 @@ public:
             streaming::prepare_message msg, UUID plan_id, sstring description, rpc::optional<streaming::stream_reason> reason)>&& func);
     future<streaming::prepare_message> send_prepare_message(msg_addr id, streaming::prepare_message msg, UUID plan_id,
             sstring description, streaming::stream_reason);
+    future<> unregister_prepare_message();
 
     // Wrapper for PREPARE_DONE_MESSAGE verb
     void register_prepare_done_message(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, unsigned dst_cpu_id)>&& func);
     future<> send_prepare_done_message(msg_addr id, UUID plan_id, unsigned dst_cpu_id);
+    future<> unregister_prepare_done_message();
 
     // Wrapper for STREAM_MUTATION verb
     void register_stream_mutation(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, frozen_mutation fm, unsigned dst_cpu_id, rpc::optional<bool>, rpc::optional<streaming::stream_reason>)>&& func);
@@ -288,6 +290,7 @@ public:
     // Wrapper for STREAM_MUTATION_FRAGMENTS
     // The receiver of STREAM_MUTATION_FRAGMENTS sends status code to the sender to notify any error on the receiver side. The status code is of type int32_t. 0 means successful, -1 means error, other status code value are reserved for future use.
     void register_stream_mutation_fragments(std::function<future<rpc::sink<int32_t>> (const rpc::client_info& cinfo, UUID plan_id, UUID schema_id, UUID cf_id, uint64_t estimated_partitions, rpc::optional<streaming::stream_reason> reason_opt, rpc::source<frozen_mutation_fragment, rpc::optional<streaming::stream_mutation_fragments_cmd>> source)>&& func);
+    future<> unregister_stream_mutation_fragments();
     rpc::sink<int32_t> make_sink_for_stream_mutation_fragments(rpc::source<frozen_mutation_fragment, rpc::optional<streaming::stream_mutation_fragments_cmd>>& source);
     future<rpc::sink<frozen_mutation_fragment, streaming::stream_mutation_fragments_cmd>, rpc::source<int32_t>> make_sink_and_source_for_stream_mutation_fragments(utils::UUID schema_id, utils::UUID plan_id, utils::UUID cf_id, uint64_t estimated_partitions, streaming::stream_reason reason, msg_addr id);
 
@@ -295,22 +298,27 @@ public:
     future<rpc::sink<repair_hash_with_cmd>, rpc::source<repair_row_on_wire_with_cmd>> make_sink_and_source_for_repair_get_row_diff_with_rpc_stream(uint32_t repair_meta_id, msg_addr id);
     rpc::sink<repair_row_on_wire_with_cmd> make_sink_for_repair_get_row_diff_with_rpc_stream(rpc::source<repair_hash_with_cmd>& source);
     void register_repair_get_row_diff_with_rpc_stream(std::function<future<rpc::sink<repair_row_on_wire_with_cmd>> (const rpc::client_info& cinfo, uint32_t repair_meta_id, rpc::source<repair_hash_with_cmd> source)>&& func);
+    future<> unregister_repair_get_row_diff_with_rpc_stream();
 
     // Wrapper for REPAIR_PUT_ROW_DIFF_WITH_RPC_STREAM
     future<rpc::sink<repair_row_on_wire_with_cmd>, rpc::source<repair_stream_cmd>> make_sink_and_source_for_repair_put_row_diff_with_rpc_stream(uint32_t repair_meta_id, msg_addr id);
     rpc::sink<repair_stream_cmd> make_sink_for_repair_put_row_diff_with_rpc_stream(rpc::source<repair_row_on_wire_with_cmd>& source);
     void register_repair_put_row_diff_with_rpc_stream(std::function<future<rpc::sink<repair_stream_cmd>> (const rpc::client_info& cinfo, uint32_t repair_meta_id, rpc::source<repair_row_on_wire_with_cmd> source)>&& func);
+    future<> unregister_repair_put_row_diff_with_rpc_stream();
 
     // Wrapper for REPAIR_GET_FULL_ROW_HASHES_WITH_RPC_STREAM
     future<rpc::sink<repair_stream_cmd>, rpc::source<repair_hash_with_cmd>> make_sink_and_source_for_repair_get_full_row_hashes_with_rpc_stream(uint32_t repair_meta_id, msg_addr id);
     rpc::sink<repair_hash_with_cmd> make_sink_for_repair_get_full_row_hashes_with_rpc_stream(rpc::source<repair_stream_cmd>& source);
     void register_repair_get_full_row_hashes_with_rpc_stream(std::function<future<rpc::sink<repair_hash_with_cmd>> (const rpc::client_info& cinfo, uint32_t repair_meta_id, rpc::source<repair_stream_cmd> source)>&& func);
+    future<> unregister_repair_get_full_row_hashes_with_rpc_stream();
 
     void register_stream_mutation_done(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, dht::token_range_vector ranges, UUID cf_id, unsigned dst_cpu_id)>&& func);
     future<> send_stream_mutation_done(msg_addr id, UUID plan_id, dht::token_range_vector ranges, UUID cf_id, unsigned dst_cpu_id);
+    future<> unregister_stream_mutation_done();
 
     void register_complete_message(std::function<future<> (const rpc::client_info& cinfo, UUID plan_id, unsigned dst_cpu_id, rpc::optional<bool> failed)>&& func);
     future<> send_complete_message(msg_addr id, UUID plan_id, unsigned dst_cpu_id, bool failed = false);
+    future<> unregister_complete_message();
 
     // Wrapper for REPAIR_CHECKSUM_RANGE verb
     void register_repair_checksum_range(std::function<future<partition_checksum> (sstring keyspace, sstring cf, dht::token_range range, rpc::optional<repair_checksum> hash_version)>&& func);
@@ -318,9 +326,9 @@ public:
     future<partition_checksum> send_repair_checksum_range(msg_addr id, sstring keyspace, sstring cf, dht::token_range range, repair_checksum hash_version);
 
     // Wrapper for REPAIR_GET_FULL_ROW_HASHES
-    void register_repair_get_full_row_hashes(std::function<future<std::unordered_set<repair_hash>> (const rpc::client_info& cinfo, uint32_t repair_meta_id)>&& func);
+    void register_repair_get_full_row_hashes(std::function<future<repair_hash_set> (const rpc::client_info& cinfo, uint32_t repair_meta_id)>&& func);
     future<> unregister_repair_get_full_row_hashes();
-    future<std::unordered_set<repair_hash>> send_repair_get_full_row_hashes(msg_addr id, uint32_t repair_meta_id);
+    future<repair_hash_set> send_repair_get_full_row_hashes(msg_addr id, uint32_t repair_meta_id);
 
     // Wrapper for REPAIR_GET_COMBINED_ROW_HASH
     void register_repair_get_combined_row_hash(std::function<future<get_combined_row_hash_response> (const rpc::client_info& cinfo, uint32_t repair_meta_id, std::optional<repair_sync_boundary> common_sync_boundary)>&& func);
@@ -333,9 +341,9 @@ public:
     future<get_sync_boundary_response> send_repair_get_sync_boundary(msg_addr id, uint32_t repair_meta_id, std::optional<repair_sync_boundary> skipped_sync_boundary);
 
     // Wrapper for REPAIR_GET_ROW_DIFF
-    void register_repair_get_row_diff(std::function<future<repair_rows_on_wire> (const rpc::client_info& cinfo, uint32_t repair_meta_id, std::unordered_set<repair_hash> set_diff, bool needs_all_rows)>&& func);
+    void register_repair_get_row_diff(std::function<future<repair_rows_on_wire> (const rpc::client_info& cinfo, uint32_t repair_meta_id, repair_hash_set set_diff, bool needs_all_rows)>&& func);
     future<> unregister_repair_get_row_diff();
-    future<repair_rows_on_wire> send_repair_get_row_diff(msg_addr id, uint32_t repair_meta_id, std::unordered_set<repair_hash> set_diff, bool needs_all_rows);
+    future<repair_rows_on_wire> send_repair_get_row_diff(msg_addr id, uint32_t repair_meta_id, repair_hash_set set_diff, bool needs_all_rows);
 
     // Wrapper for REPAIR_PUT_ROW_DIFF
     void register_repair_put_row_diff(std::function<future<> (const rpc::client_info& cinfo, uint32_t repair_meta_id, repair_rows_on_wire row_diff)>&& func);

multishard_mutation_query.cc

@@ -195,6 +195,7 @@ class read_context : public reader_lifecycle_policy {
 
     // One for each shard. Index is shard id.
     std::vector<reader_meta> _readers;
+    std::vector<reader_concurrency_semaphore*> _semaphores;
 
     gate _dismantling_gate;
 
@@ -211,7 +212,8 @@ public:
             , _schema(std::move(s))
             , _cmd(cmd)
             , _ranges(ranges)
-            , _trace_state(std::move(trace_state)) {
+            , _trace_state(std::move(trace_state))
+            , _semaphores(smp::count, nullptr) {
         _readers.resize(smp::count);
     }
 
@@ -236,7 +238,12 @@ public:
     virtual void destroy_reader(shard_id shard, future<stopped_reader> reader_fut) noexcept override;
 
     virtual reader_concurrency_semaphore& semaphore() override {
-        return _readers[this_shard_id()].rparts->semaphore;
+        const auto shard = this_shard_id();
+        if (!_semaphores[shard]) {
+            auto& table = _db.local().find_column_family(_schema);
+            _semaphores[shard] = &table.read_concurrency_semaphore();
+        }
+        return *_semaphores[shard];
     }
 
     future<> lookup_readers();

mutation_partition.cc

@@ -734,56 +734,78 @@ void write_counter_cell(RowWriter& w, const query::partition_slice& slice, ::ato
   });
 }
 
-// Used to return the timestamp of the latest update to the row
-struct max_timestamp {
-    api::timestamp_type max = api::missing_timestamp;
-
-    void update(api::timestamp_type ts) {
-        max = std::max(max, ts);
-    }
-};
-
-template<>
-struct appending_hash<row> {
-    template<typename Hasher>
-    void operator()(Hasher& h, const row& cells, const schema& s, column_kind kind, const query::column_id_vector& columns, max_timestamp& max_ts) const {
-        for (auto id : columns) {
-            const cell_and_hash* cell_and_hash = cells.find_cell_and_hash(id);
-            if (!cell_and_hash) {
-                return;
-            }
-            auto&& def = s.column_at(kind, id);
-            if (def.is_atomic()) {
-                max_ts.update(cell_and_hash->cell.as_atomic_cell(def).timestamp());
-                if constexpr (query::using_hash_of_hash_v<Hasher>) {
-                    if (cell_and_hash->hash) {
-                        feed_hash(h, *cell_and_hash->hash);
-                    } else {
-                        query::default_hasher cellh;
-                        feed_hash(cellh, cell_and_hash->cell.as_atomic_cell(def), def);
-                        feed_hash(h, cellh.finalize_uint64());
-                    }
+template<typename Hasher>
+void appending_hash<row>::operator()(Hasher& h, const row& cells, const schema& s, column_kind kind, const query::column_id_vector& columns, max_timestamp& max_ts) const {
+    for (auto id : columns) {
+        const cell_and_hash* cell_and_hash = cells.find_cell_and_hash(id);
+        if (!cell_and_hash) {
+            feed_hash(h, appending_hash<row>::null_hash_value);
+            continue;
+        }
+        auto&& def = s.column_at(kind, id);
+        if (def.is_atomic()) {
+            max_ts.update(cell_and_hash->cell.as_atomic_cell(def).timestamp());
+            if constexpr (query::using_hash_of_hash_v<Hasher>) {
+                if (cell_and_hash->hash) {
+                    feed_hash(h, *cell_and_hash->hash);
                 } else {
-                    feed_hash(h, cell_and_hash->cell.as_atomic_cell(def), def);
+                    query::default_hasher cellh;
+                    feed_hash(cellh, cell_and_hash->cell.as_atomic_cell(def), def);
+                    feed_hash(h, cellh.finalize_uint64());
                 }
             } else {
-                auto cm = cell_and_hash->cell.as_collection_mutation();
-                max_ts.update(cm.last_update(*def.type));
-                if constexpr (query::using_hash_of_hash_v<Hasher>) {
-                    if (cell_and_hash->hash) {
-                        feed_hash(h, *cell_and_hash->hash);
-                    } else {
-                        query::default_hasher cellh;
-                        feed_hash(cellh, cm, def);
-                        feed_hash(h, cellh.finalize_uint64());
-                    }
+                feed_hash(h, cell_and_hash->cell.as_atomic_cell(def), def);
+            }
+        } else {
+            auto cm = cell_and_hash->cell.as_collection_mutation();
+            max_ts.update(cm.last_update(*def.type));
+            if constexpr (query::using_hash_of_hash_v<Hasher>) {
+                if (cell_and_hash->hash) {
+                    feed_hash(h, *cell_and_hash->hash);
                 } else {
-                    feed_hash(h, cm, def);
+                    query::default_hasher cellh;
+                    feed_hash(cellh, cm, def);
+                    feed_hash(h, cellh.finalize_uint64());
                 }
+            } else {
+                feed_hash(h, cm, def);
             }
         }
     }
-};
+}
+// Instantiation for mutation_test.cc
+template void appending_hash<row>::operator()<xx_hasher>(xx_hasher& h, const row& cells, const schema& s, column_kind kind, const query::column_id_vector& columns, max_timestamp& max_ts) const;
+
+template<>
+void appending_hash<row>::operator()<legacy_xx_hasher_without_null_digest>(legacy_xx_hasher_without_null_digest& h, const row& cells, const schema& s, column_kind kind, const query::column_id_vector& columns, max_timestamp& max_ts) const {
+    for (auto id : columns) {
+        const cell_and_hash* cell_and_hash = cells.find_cell_and_hash(id);
+        if (!cell_and_hash) {
+            return;
+        }
+        auto&& def = s.column_at(kind, id);
+        if (def.is_atomic()) {
+            max_ts.update(cell_and_hash->cell.as_atomic_cell(def).timestamp());
+            if (cell_and_hash->hash) {
+                feed_hash(h, *cell_and_hash->hash);
+            } else {
+                query::default_hasher cellh;
+                feed_hash(cellh, cell_and_hash->cell.as_atomic_cell(def), def);
+                feed_hash(h, cellh.finalize_uint64());
+            }
+        } else {
+            auto cm = cell_and_hash->cell.as_collection_mutation();
+            max_ts.update(cm.last_update(*def.type));
+            if (cell_and_hash->hash) {
+                feed_hash(h, *cell_and_hash->hash);
+            } else {
+                query::default_hasher cellh;
+                feed_hash(cellh, cm, def);
+                feed_hash(h, cellh.finalize_uint64());
+            }
+        }
+    }
+}
 
 cell_hash_opt row::cell_hash_for(column_id id) const {
     if (_type == storage_type::vector) {
@@ -1721,7 +1743,7 @@ void row::apply_monotonically(const schema& s, column_kind kind, row&& other) {
 // we erase the live cells according to the shadowable_tombstone rules.
 static bool dead_marker_shadows_row(const schema& s, column_kind kind, const row_marker& marker) {
     return s.is_view()
-            && !s.view_info()->base_non_pk_columns_in_view_pk().empty()
+            && s.view_info()->has_base_non_pk_columns_in_view_pk()
             && !marker.is_live()
             && kind == column_kind::regular_column; // not applicable to static rows
 }
@@ -2505,7 +2527,8 @@ mutation_partition::fully_discontinuous(const schema& s, const position_range& r
 future<mutation_opt> counter_write_query(schema_ptr s, const mutation_source& source,
                                          const dht::decorated_key& dk,
                                          const query::partition_slice& slice,
-                                         tracing::trace_state_ptr trace_ptr)
+                                         tracing::trace_state_ptr trace_ptr,
+                                         db::timeout_clock::time_point timeout)
 {
     struct range_and_reader {
         dht::partition_range range;
@@ -2530,7 +2553,7 @@ future<mutation_opt> counter_write_query(schema_ptr s, const mutation_source& so
     auto cwqrb = counter_write_query_result_builder(*s);
     auto cfq = make_stable_flattened_mutations_consumer<compact_for_query<emit_only_live_rows::yes, counter_write_query_result_builder>>(
             *s, gc_clock::now(), slice, query::max_rows, query::max_rows, std::move(cwqrb));
-    auto f = r_a_r->reader.consume(std::move(cfq), db::no_timeout);
+    auto f = r_a_r->reader.consume(std::move(cfq), timeout);
     return f.finally([r_a_r = std::move(r_a_r)] { });
 }
 
@@ -2605,7 +2628,7 @@ void mutation_cleaner_impl::start_worker() {
 stop_iteration mutation_cleaner_impl::merge_some(partition_snapshot& snp) noexcept {
     auto&& region = snp.region();
     return with_allocator(region.allocator(), [&] {
-        return with_linearized_managed_bytes([&] {
+        {
             // Allocating sections require the region to be reclaimable
             // which means that they cannot be nested.
             // It is, however, possible, that if the snapshot is taken
@@ -2617,13 +2640,15 @@ stop_iteration mutation_cleaner_impl::merge_some(partition_snapshot& snp) noexce
             }
             try {
                 return _worker_state->alloc_section(region, [&] {
+                  return with_linearized_managed_bytes([&] {
                     return snp.merge_partition_versions(_app_stats);
+                  });
                 });
             } catch (...) {
                 // Merging failed, give up as there is no guarantee of forward progress.
                 return stop_iteration::yes;
             }
-        });
+        }
     });
 }
 

mutation_partition.hh

@@ -650,6 +650,22 @@ public:
     };
 };
 
+// Used to return the timestamp of the latest update to the row
+struct max_timestamp {
+    api::timestamp_type max = api::missing_timestamp;
+
+    void update(api::timestamp_type ts) {
+        max = std::max(max, ts);
+    }
+};
+
+template<>
+struct appending_hash<row> {
+    static constexpr int null_hash_value = 0xbeefcafe;
+    template<typename Hasher>
+    void operator()(Hasher& h, const row& cells, const schema& s, column_kind kind, const query::column_id_vector& columns, max_timestamp& max_ts) const;
+};
+
 class row_marker;
 int compare_row_marker_for_merge(const row_marker& left, const row_marker& right) noexcept;
 

mutation_query.hh

@@ -113,9 +113,6 @@ class reconcilable_result_builder {
     const schema& _schema;
     const query::partition_slice& _slice;
 
-    utils::chunked_vector<partition> _result;
-    uint32_t _live_rows{};
-
     bool _return_static_content_on_partition_with_no_rows{};
     bool _static_row_is_alive{};
     uint32_t _total_live_rows = 0;
@@ -123,6 +120,10 @@ class reconcilable_result_builder {
     stop_iteration _stop;
     bool _short_read_allowed;
     std::optional<streamed_mutation_freezer> _mutation_consumer;
+
+    uint32_t _live_rows{};
+    // make this the last member so it is destroyed first. #7240
+    utils::chunked_vector<partition> _result;
 public:
     reconcilable_result_builder(const schema& s, const query::partition_slice& slice,
                                 query::result_memory_accounter&& accounter)
@@ -206,5 +207,6 @@ public:
 future<mutation_opt> counter_write_query(schema_ptr, const mutation_source&,
                                          const dht::decorated_key& dk,
                                          const query::partition_slice& slice,
-                                         tracing::trace_state_ptr trace_ptr);
+                                         tracing::trace_state_ptr trace_ptr,
+                                         db::timeout_clock::time_point timeout);
 

mutation_reader.hh

@@ -372,6 +372,64 @@ flat_mutation_reader make_foreign_reader(schema_ptr schema,
         foreign_ptr<std::unique_ptr<flat_mutation_reader>> reader,
         streamed_mutation::forwarding fwd_sm = streamed_mutation::forwarding::no);
 
+/// Make an auto-paused evictable reader.
+///
+/// The reader is paused after each use, that is after each call to any of its
+/// members that cause actual reading to be done (`fill_buffer()` and
+/// `fast_forward_to()`). When paused, the reader is made evictable, that it is
+/// it is registered with reader concurrency semaphore as an inactive read.
+/// The reader is resumed automatically on the next use. If it was evicted, it
+/// will be recreated at the position it left off reading. This is all
+/// transparent to its user.
+/// Parameters passed by reference have to be kept alive while the reader is
+/// alive.
+flat_mutation_reader make_auto_paused_evictable_reader(
+        mutation_source ms,
+        schema_ptr schema,
+        reader_concurrency_semaphore& semaphore,
+        const dht::partition_range& pr,
+        const query::partition_slice& ps,
+        const io_priority_class& pc,
+        tracing::trace_state_ptr trace_state,
+        mutation_reader::forwarding fwd_mr);
+
+class evictable_reader;
+
+class evictable_reader_handle {
+    friend std::pair<flat_mutation_reader, evictable_reader_handle> make_manually_paused_evictable_reader(mutation_source, schema_ptr, reader_concurrency_semaphore&,
+            const dht::partition_range&, const query::partition_slice&, const io_priority_class&, tracing::trace_state_ptr, mutation_reader::forwarding);
+
+private:
+    evictable_reader* _r;
+
+private:
+    explicit evictable_reader_handle(evictable_reader& r);
+
+public:
+    void pause();
+};
+
+/// Make a manually-paused evictable reader.
+///
+/// The reader can be paused via the evictable reader handle when desired. The
+/// intended usage is subsequent reads done in bursts, after which the reader is
+/// not used for some time. When paused, the reader is made evictable, that is,
+/// it is registered with reader concurrency semaphore as an inactive read.
+/// The reader is resumed automatically on the next use. If it was evicted, it
+/// will be recreated at the position it left off reading. This is all
+/// transparent to its user.
+/// Parameters passed by reference have to be kept alive while the reader is
+/// alive.
+std::pair<flat_mutation_reader, evictable_reader_handle> make_manually_paused_evictable_reader(
+        mutation_source ms,
+        schema_ptr schema,
+        reader_concurrency_semaphore& semaphore,
+        const dht::partition_range& pr,
+        const query::partition_slice& ps,
+        const io_priority_class& pc,
+        tracing::trace_state_ptr trace_state,
+        mutation_reader::forwarding fwd_mr);
+
 /// Reader lifecycle policy for the mulitshard combining reader.
 ///
 /// This policy is expected to make sure any additional resource the readers

mutation_writer/feed_writers.hh

@@ -38,8 +38,14 @@ future<> feed_writer(flat_mutation_reader&& rd, Writer&& wr) {
                 auto f2 = rd.is_buffer_empty() ? rd.fill_buffer(db::no_timeout) : make_ready_future<>();
                 return when_all_succeed(std::move(f1), std::move(f2));
             });
-        }).finally([&wr] {
-            return wr.consume_end_of_stream();
+        }).then_wrapped([&wr] (future<> f) {
+            if (f.failed()) {
+                auto ex = f.get_exception();
+                wr.abort(ex);
+                return make_exception_future<>(ex);
+            } else {
+                return wr.consume_end_of_stream();
+            }
         });
     });
 }

mutation_writer/shard_based_splitting_writer.cc

@@ -57,6 +57,9 @@ class shard_based_splitting_mutation_writer {
             }
             return std::move(_consume_fut);
         }
+        void abort(std::exception_ptr ep) {
+            _handle.abort(ep);
+        }
     };
 
 private:
@@ -108,6 +111,13 @@ public:
             return shard->consume_end_of_stream();
         });
     }
+    void abort(std::exception_ptr ep) {
+        for (auto&& shard : _shards) {
+            if (shard) {
+                shard->abort(ep);
+            }
+        }
+    }
 };
 
 future<> segregate_by_shard(flat_mutation_reader producer, reader_consumer consumer) {

mutation_writer/timestamp_based_splitting_writer.cc

@@ -144,6 +144,9 @@ class timestamp_based_splitting_mutation_writer {
             }
             return std::move(_consume_fut);
         }
+        void abort(std::exception_ptr ep) {
+            _handle.abort(ep);
+        }
     };
 
 private:
@@ -186,6 +189,11 @@ public:
             return bucket.second.consume_end_of_stream();
         });
     }
+    void abort(std::exception_ptr ep) {
+        for (auto&& b : _buckets) {
+            b.second.abort(ep);
+        }
+    }
 };
 
 future<> timestamp_based_splitting_mutation_writer::write_to_bucket(bucket_id bucket, mutation_fragment&& mf) {

partition_version.cc

@@ -650,12 +650,12 @@ partition_snapshot_ptr partition_entry::read(logalloc::region& r,
     return partition_snapshot_ptr(std::move(snp));
 }
 
-std::vector<range_tombstone>
+partition_snapshot::range_tombstone_result
 partition_snapshot::range_tombstones(position_in_partition_view start, position_in_partition_view end)
 {
     partition_version* v = &*version();
     if (!v->next()) {
-        return boost::copy_range<std::vector<range_tombstone>>(
+        return boost::copy_range<range_tombstone_result>(
             v->partition().row_tombstones().slice(*_schema, start, end));
     }
     range_tombstone_list list(*_schema);
@@ -665,10 +665,10 @@ partition_snapshot::range_tombstones(position_in_partition_view start, position_
         }
         v = v->next();
     }
-    return boost::copy_range<std::vector<range_tombstone>>(list.slice(*_schema, start, end));
+    return boost::copy_range<range_tombstone_result>(list.slice(*_schema, start, end));
 }
 
-std::vector<range_tombstone>
+partition_snapshot::range_tombstone_result
 partition_snapshot::range_tombstones()
 {
     return range_tombstones(

partition_version.hh

@@ -26,6 +26,7 @@
 #include "utils/anchorless_list.hh"
 #include "utils/logalloc.hh"
 #include "utils/coroutine.hh"
+#include "utils/chunked_vector.hh"
 
 #include <boost/intrusive/parent_from_member.hpp>
 #include <boost/intrusive/slist.hpp>
@@ -400,10 +401,13 @@ public:
     ::static_row static_row(bool digest_requested) const;
     bool static_row_continuous() const;
     mutation_partition squashed() const;
+
+    using range_tombstone_result = utils::chunked_vector<range_tombstone>;
+
     // Returns range tombstones overlapping with [start, end)
-    std::vector<range_tombstone> range_tombstones(position_in_partition_view start, position_in_partition_view end);
+    range_tombstone_result range_tombstones(position_in_partition_view start, position_in_partition_view end);
     // Returns all range tombstones
-    std::vector<range_tombstone> range_tombstones();
+    range_tombstone_result range_tombstones();
 };
 
 class partition_snapshot_ptr {

position_in_partition.hh

@@ -163,6 +163,11 @@ public:
         return {partition_region::clustered, bound_weight::before_all_prefixed, &ck};
     }
 
+    // Returns a view to before_key(pos._ck) if pos.is_clustering_row() else returns pos as-is.
+    static position_in_partition_view before_key(position_in_partition_view pos) {
+        return {partition_region::clustered, pos._bound_weight == bound_weight::equal ? bound_weight::before_all_prefixed : pos._bound_weight, pos._ck};
+    }
+
     partition_region region() const { return _type; }
     bound_weight get_bound_weight() const { return _bound_weight; }
     bool is_partition_start() const { return _type == partition_region::partition_start; }

reader_concurrency_semaphore.cc

@@ -27,6 +27,7 @@
 
 
 reader_permit::impl::impl(reader_concurrency_semaphore& semaphore, reader_resources base_cost) : semaphore(semaphore), base_cost(base_cost) {
+    semaphore.consume(base_cost);
 }
 
 reader_permit::impl::~impl() {
@@ -88,7 +89,6 @@ void reader_concurrency_semaphore::signal(const resources& r) noexcept {
     _resources += r;
     while (!_wait_list.empty() && has_available_units(_wait_list.front().res)) {
         auto& x = _wait_list.front();
-        _resources -= x.res;
         try {
             x.pr.set_value(reader_permit(*this, x.res));
         } catch (...) {
@@ -160,7 +160,6 @@ future<reader_permit> reader_concurrency_semaphore::wait_admission(size_t memory
         --_inactive_read_stats.population;
     }
     if (may_proceed(r)) {
-        _resources -= r;
         return make_ready_future<reader_permit>(reader_permit(*this, r));
     }
     promise<reader_permit> pr;
@@ -170,7 +169,6 @@ future<reader_permit> reader_concurrency_semaphore::wait_admission(size_t memory
 }
 
 reader_permit reader_concurrency_semaphore::consume_resources(resources r) {
-    _resources -= r;
     return reader_permit(*this, r);
 }
 

reader_concurrency_semaphore.hh

@@ -128,6 +128,10 @@ private:
         return has_available_units(r) && _wait_list.empty();
     }
 
+    void consume(resources r) {
+        _resources -= r;
+    }
+
     void consume_memory(size_t memory) {
         _resources.memory -= memory;
     }

redis/commands.cc

@@ -63,7 +63,7 @@ shared_ptr<abstract_command> exists::prepare(service::storage_proxy& proxy, requ
 }
 
 future<redis_message> exists::execute(service::storage_proxy& proxy, redis::redis_options& options, service_permit permit) {
-    return seastar::do_for_each(_keys, [&proxy, &options, &permit, this] (bytes key) {
+    return seastar::do_for_each(_keys, [&proxy, &options, permit, this] (bytes& key) {
         return redis::read_strings(proxy, options, key, permit).then([this] (lw_shared_ptr<strings_result> result) {
             if (result->has_result()) {
                 _count++;

reloc/get-dynamic-linker.sh

@@ -12,7 +12,11 @@
 # At the end of the build we check that the build-id is indeed in the
 # first page. At install time we check that patchelf doesn't modify
 # the program headers.
+
+# gdb has a SO_NAME_MAX_PATH_SIZE of 512, so limit the path size to
+# that. The 512 includes the null at the end, hence the 511 bellow.
+
 ORIGINAL_DYNAMIC_LINKER=$(gcc -### /dev/null -o t 2>&1 | perl -n  -e '/-dynamic-linker ([^ ]*) / && print $1')
-DYNAMIC_LINKER=$(printf "%2000s$ORIGINAL_DYNAMIC_LINKER" | sed 's| |/|g')
+DYNAMIC_LINKER=$(printf "%511s$ORIGINAL_DYNAMIC_LINKER" | sed 's| |/|g')
 
 echo $DYNAMIC_LINKER

repair/repair.cc

@@ -1945,7 +1945,7 @@ future<> rebuild_with_repair(seastar::sharded<database>& db, locator::token_meta
 future<> replace_with_repair(seastar::sharded<database>& db, locator::token_metadata tm, std::unordered_set<dht::token> replacing_tokens) {
     auto op = sstring("replace_with_repair");
     auto source_dc = get_local_dc();
-    auto reason = streaming::stream_reason::bootstrap;
+    auto reason = streaming::stream_reason::replace;
     tm.update_normal_tokens(replacing_tokens, utils::fb_utilities::get_broadcast_address());
     return do_rebuild_replace_with_repair(db, std::move(tm), std::move(op), std::move(source_dc), reason);
 }

repair/repair.hh

@@ -23,6 +23,7 @@
 
 #include <unordered_map>
 #include <exception>
+#include <absl/container/btree_set.h>
 
 #include <seastar/core/sstring.hh>
 #include <seastar/core/sharded.hh>
@@ -334,6 +335,8 @@ public:
     }
 };
 
+using repair_hash_set = absl::btree_set<repair_hash>;
+
 // Return value of the REPAIR_GET_SYNC_BOUNDARY RPC verb
 struct get_sync_boundary_response {
     std::optional<repair_sync_boundary> boundary;

repair/row_level.cc

@@ -47,6 +47,7 @@
 #include "gms/gossiper.hh"
 #include "repair/row_level.hh"
 #include "mutation_source_metadata.hh"
+#include "utils/stall_free.hh"
 
 extern logging::logger rlogger;
 
@@ -372,6 +373,7 @@ private:
     std::optional<utils::phased_barrier::operation> _local_read_op;
     // Local reader or multishard reader to read the range
     flat_mutation_reader _reader;
+    std::optional<evictable_reader_handle> _reader_handle;
     // Current partition read from disk
     lw_shared_ptr<const decorated_key_with_hash> _current_dk;
 
@@ -390,32 +392,49 @@ public:
             , _sharder(remote_sharder, range, remote_shard)
             , _seed(seed)
             , _local_read_op(local_reader ? std::optional(cf.read_in_progress()) : std::nullopt)
-            , _reader(make_reader(db, cf, local_reader)) {
-    }
-
-private:
-    flat_mutation_reader
-    make_reader(seastar::sharded<database>& db,
-            column_family& cf,
-            is_local_reader local_reader) {
+            , _reader(nullptr) {
         if (local_reader) {
-            return cf.make_streaming_reader(_schema, _range);
+            auto ms = mutation_source([&cf] (
+                        schema_ptr s,
+                        reader_permit,
+                        const dht::partition_range& pr,
+                        const query::partition_slice& ps,
+                        const io_priority_class& pc,
+                        tracing::trace_state_ptr,
+                        streamed_mutation::forwarding,
+                        mutation_reader::forwarding fwd_mr) {
+                return cf.make_streaming_reader(std::move(s), pr, ps, fwd_mr);
+            });
+            std::tie(_reader, _reader_handle) = make_manually_paused_evictable_reader(
+                    std::move(ms),
+                    _schema,
+                    cf.streaming_read_concurrency_semaphore(),
+                    _range,
+                    _schema->full_slice(),
+                    service::get_local_streaming_read_priority(),
+                    {},
+                    mutation_reader::forwarding::no);
+        } else {
+            _reader = make_multishard_streaming_reader(db, _schema, [this] {
+                auto shard_range = _sharder.next();
+                if (shard_range) {
+                    return std::optional<dht::partition_range>(dht::to_partition_range(*shard_range));
+                }
+                return std::optional<dht::partition_range>();
+            });
         }
-        return make_multishard_streaming_reader(db, _schema, [this] {
-            auto shard_range = _sharder.next();
-            if (shard_range) {
-                return std::optional<dht::partition_range>(dht::to_partition_range(*shard_range));
-            }
-            return std::optional<dht::partition_range>();
-        });
     }
 
-public:
     future<mutation_fragment_opt>
     read_mutation_fragment() {
         return _reader(db::no_timeout);
     }
 
+    void on_end_of_stream() {
+        _reader = make_empty_flat_reader(_schema);
+        _reader_handle.reset();
+    }
+
     lw_shared_ptr<const decorated_key_with_hash>& get_current_dk() {
         return _current_dk;
     }
@@ -434,9 +453,14 @@ public:
         }
     }
 
+    void pause() {
+        if (_reader_handle) {
+            _reader_handle->pause();
+        }
+    }
 };
 
-class repair_writer {
+class repair_writer : public enable_lw_shared_from_this<repair_writer> {
     schema_ptr _schema;
     uint64_t _estimated_partitions;
     size_t _nr_peer_nodes;
@@ -450,6 +474,7 @@ class repair_writer {
     // written.
     std::vector<bool> _partition_opened;
     streaming::stream_reason _reason;
+    named_semaphore _sem{1, named_semaphore_exception_factory{"repair_writer"}};
 public:
     repair_writer(
             schema_ptr schema,
@@ -494,9 +519,10 @@ public:
             return _mq[node_idx]->pop_eventually();
         };
         table& t = db.local().find_column_family(_schema->id());
+        auto writer = shared_from_this();
         _writer_done[node_idx] = mutation_writer::distribute_reader_and_consume_on_shards(_schema,
                 make_generating_reader(_schema, std::move(get_next_mutation_fragment)),
-                [&db, reason = this->_reason, estimated_partitions = this->_estimated_partitions] (flat_mutation_reader reader) {
+                [&db, reason = this->_reason, estimated_partitions = this->_estimated_partitions, writer] (flat_mutation_reader reader) {
             auto& t = db.local().find_column_family(reader.schema());
             return db::view::check_needs_view_update_path(_sys_dist_ks->local(), t, reason).then([t = t.shared_from_this(), estimated_partitions, reader = std::move(reader)] (bool use_view_update_path) mutable {
                 //FIXME: for better estimations this should be transmitted from remote
@@ -508,7 +534,7 @@ public:
                     sstables::shared_sstable sst = use_view_update_path ? t->make_streaming_staging_sstable() : t->make_streaming_sstable_for_write();
                     schema_ptr s = reader.schema();
                     auto& pc = service::get_local_streaming_write_priority();
-                    return sst->write_components(std::move(reader), std::max(1ul, adjusted_estimated_partitions), s,
+                    return sst->write_components(std::move(reader), adjusted_estimated_partitions, s,
                                                  t->get_sstables_manager().configure_writer(),
                                                  encoding_stats{}, pc).then([sst] {
                         return sst->open_data();
@@ -524,13 +550,13 @@ public:
                 return consumer(std::move(reader));
             });
         },
-        t.stream_in_progress()).then([this, node_idx] (uint64_t partitions) {
+        t.stream_in_progress()).then([node_idx, writer] (uint64_t partitions) {
             rlogger.debug("repair_writer: keyspace={}, table={}, managed to write partitions={} to sstable",
-                _schema->ks_name(), _schema->cf_name(), partitions);
-        }).handle_exception([this, node_idx] (std::exception_ptr ep) {
+                writer->_schema->ks_name(), writer->_schema->cf_name(), partitions);
+        }).handle_exception([node_idx, writer] (std::exception_ptr ep) {
             rlogger.warn("repair_writer: keyspace={}, table={}, multishard_writer failed: {}",
-                    _schema->ks_name(), _schema->cf_name(), ep);
-            _mq[node_idx]->abort(ep);
+                    writer->_schema->ks_name(), writer->_schema->cf_name(), ep);
+            writer->_mq[node_idx]->abort(ep);
             return make_exception_future<>(std::move(ep));
         });
     }
@@ -561,11 +587,18 @@ public:
 
     future<> write_end_of_stream(unsigned node_idx) {
         if (_mq[node_idx]) {
+          return with_semaphore(_sem, 1, [this, node_idx] {
             // Partition_end is never sent on wire, so we have to write one ourselves.
             return write_partition_end(node_idx).then([this, node_idx] () mutable {
                 // Empty mutation_fragment_opt means no more data, so the writer can seal the sstables.
                 return _mq[node_idx]->push_eventually(mutation_fragment_opt());
+            }).handle_exception([this, node_idx] (std::exception_ptr ep) {
+                _mq[node_idx]->abort(ep);
+                rlogger.warn("repair_writer: keyspace={}, table={}, write_end_of_stream failed: {}",
+                        _schema->ks_name(), _schema->cf_name(), ep);
+                return make_exception_future<>(std::move(ep));
             });
+          });
         } else {
             return make_ready_future<>();
         }
@@ -588,6 +621,10 @@ public:
             return make_exception_future<>(std::move(ep));
         });
     }
+
+    named_semaphore& sem() {
+        return _sem;
+    }
 };
 
 class repair_meta {
@@ -623,7 +660,7 @@ private:
     size_t _nr_peer_nodes= 1;
     repair_stats _stats;
     repair_reader _repair_reader;
-    repair_writer _repair_writer;
+    lw_shared_ptr<repair_writer> _repair_writer;
     // Contains rows read from disk
     std::list<repair_row> _row_buf;
     // Contains rows we are working on to sync between peers
@@ -635,7 +672,7 @@ private:
     // Tracks current sync boundary
     std::optional<repair_sync_boundary> _current_sync_boundary;
     // Contains the hashes of rows in the _working_row_buffor for all peer nodes
-    std::vector<std::unordered_set<repair_hash>> _peer_row_hash_sets;
+    std::vector<repair_hash_set> _peer_row_hash_sets;
     // Gate used to make sure pending operation of meta data is done
     seastar::gate _gate;
     sink_source_for_get_full_row_hashes _sink_source_for_get_full_row_hashes;
@@ -704,7 +741,7 @@ public:
                     _seed,
                     repair_reader::is_local_reader(_repair_master || _same_sharding_config)
               )
-            , _repair_writer(_schema, _estimated_partitions, _nr_peer_nodes, _reason)
+            , _repair_writer(make_lw_shared<repair_writer>(_schema, _estimated_partitions, _nr_peer_nodes, _reason))
             , _sink_source_for_get_full_row_hashes(_repair_meta_id, _nr_peer_nodes,
                     [] (uint32_t repair_meta_id, netw::messaging_service::msg_addr addr) {
                         return netw::get_local_messaging_service().make_sink_and_source_for_repair_get_full_row_hashes_with_rpc_stream(repair_meta_id, addr);
@@ -723,11 +760,12 @@ public:
 public:
     future<> stop() {
         auto gate_future = _gate.close();
-        auto writer_future = _repair_writer.wait_for_writer_done();
         auto f1 = _sink_source_for_get_full_row_hashes.close();
         auto f2 = _sink_source_for_get_row_diff.close();
         auto f3 = _sink_source_for_put_row_diff.close();
-        return when_all_succeed(std::move(gate_future), std::move(writer_future), std::move(f1), std::move(f2), std::move(f3));
+        return when_all_succeed(std::move(gate_future), std::move(f1), std::move(f2), std::move(f3)).finally([this] {
+            return _repair_writer->wait_for_writer_done();
+        });
     }
 
     static std::unordered_map<node_repair_meta_id, lw_shared_ptr<repair_meta>>& repair_meta_map() {
@@ -855,9 +893,9 @@ public:
     }
 
     // Must run inside a seastar thread
-    static std::unordered_set<repair_hash>
-    get_set_diff(const std::unordered_set<repair_hash>& x, const std::unordered_set<repair_hash>& y) {
-        std::unordered_set<repair_hash> set_diff;
+    static repair_hash_set
+    get_set_diff(const repair_hash_set& x, const repair_hash_set& y) {
+        repair_hash_set set_diff;
         // Note std::set_difference needs x and y are sorted.
         std::copy_if(x.begin(), x.end(), std::inserter(set_diff, set_diff.end()),
                 [&y] (auto& item) { thread::maybe_yield(); return y.find(item) == y.end(); });
@@ -875,14 +913,14 @@ public:
 
     }
 
-    std::unordered_set<repair_hash>& peer_row_hash_sets(unsigned node_idx) {
+    repair_hash_set& peer_row_hash_sets(unsigned node_idx) {
         return _peer_row_hash_sets[node_idx];
     }
 
     // Get a list of row hashes in _working_row_buf
-    future<std::unordered_set<repair_hash>>
+    future<repair_hash_set>
     working_row_hashes() {
-        return do_with(std::unordered_set<repair_hash>(), [this] (std::unordered_set<repair_hash>& hashes) {
+        return do_with(repair_hash_set(), [this] (repair_hash_set& hashes) {
             return do_for_each(_working_row_buf, [&hashes] (repair_row& r) {
                 hashes.emplace(r.hash());
             }).then([&hashes] {
@@ -1007,11 +1045,7 @@ private:
         return repair_hash(h.finalize_uint64());
     }
 
-    stop_iteration handle_mutation_fragment(mutation_fragment_opt mfopt, size_t& cur_size, size_t& new_rows_size, std::list<repair_row>& cur_rows) {
-        if (!mfopt) {
-            return stop_iteration::yes;
-        }
-        mutation_fragment& mf = *mfopt;
+    stop_iteration handle_mutation_fragment(mutation_fragment& mf, size_t& cur_size, size_t& new_rows_size, std::list<repair_row>& cur_rows) {
         if (mf.is_partition_start()) {
             auto& start = mf.as_partition_start();
             _repair_reader.set_current_dk(start.key());
@@ -1046,32 +1080,49 @@ private:
                 }
                 _gate.check();
                 return _repair_reader.read_mutation_fragment().then([this, &cur_size, &new_rows_size, &cur_rows] (mutation_fragment_opt mfopt) mutable {
-                    return handle_mutation_fragment(std::move(mfopt), cur_size, new_rows_size, cur_rows);
+                    if (!mfopt) {
+                        _repair_reader.on_end_of_stream();
+                        return stop_iteration::yes;
+                    }
+                    return handle_mutation_fragment(*mfopt, cur_size, new_rows_size, cur_rows);
                 });
-            }).then([&cur_rows, &new_rows_size] () mutable {
+            }).then_wrapped([this, &cur_rows, &new_rows_size] (future<> fut) mutable {
+                if (fut.failed()) {
+                    _repair_reader.on_end_of_stream();
+                    return make_exception_future<std::list<repair_row>, size_t>(fut.get_exception());
+                }
+                _repair_reader.pause();
                 return make_ready_future<std::list<repair_row>, size_t>(std::move(cur_rows), new_rows_size);
             });
         });
     }
 
+    future<> clear_row_buf() {
+        return utils::clear_gently(_row_buf);
+    }
+
+    future<> clear_working_row_buf() {
+        return utils::clear_gently(_working_row_buf).then([this] {
+            _working_row_buf_combined_hash.clear();
+        });
+    }
+
     // Read rows from disk until _max_row_buf_size of rows are filled into _row_buf.
     // Calculate the combined checksum of the rows
     // Calculate the total size of the rows in _row_buf
     future<get_sync_boundary_response>
     get_sync_boundary(std::optional<repair_sync_boundary> skipped_sync_boundary) {
+        auto f = make_ready_future<>();
         if (skipped_sync_boundary) {
             _current_sync_boundary = skipped_sync_boundary;
-            _row_buf.clear();
-            _working_row_buf.clear();
-            _working_row_buf_combined_hash.clear();
-        } else {
-            _working_row_buf.clear();
-            _working_row_buf_combined_hash.clear();
+            f = clear_row_buf();
         }
         // Here is the place we update _last_sync_boundary
         rlogger.trace("SET _last_sync_boundary from {} to {}", _last_sync_boundary, _current_sync_boundary);
         _last_sync_boundary = _current_sync_boundary;
-        return row_buf_size().then([this, sb = std::move(skipped_sync_boundary)] (size_t cur_size) {
+      return f.then([this, sb = std::move(skipped_sync_boundary)] () mutable {
+       return clear_working_row_buf().then([this, sb = sb] () mutable {
+        return row_buf_size().then([this, sb = std::move(sb)] (size_t cur_size) {
             return read_rows_from_disk(cur_size).then([this, sb = std::move(sb)] (std::list<repair_row> new_rows, size_t new_rows_size) mutable {
                 size_t new_rows_nr = new_rows.size();
                 _row_buf.splice(_row_buf.end(), new_rows);
@@ -1088,6 +1139,8 @@ private:
                 });
             });
         });
+       });
+      });
     }
 
     future<> move_row_buf_to_working_row_buf() {
@@ -1163,9 +1216,9 @@ private:
     }
 
     future<std::list<repair_row>>
-    copy_rows_from_working_row_buf_within_set_diff(std::unordered_set<repair_hash> set_diff) {
+    copy_rows_from_working_row_buf_within_set_diff(repair_hash_set set_diff) {
         return do_with(std::list<repair_row>(), std::move(set_diff),
-                [this] (std::list<repair_row>& rows, std::unordered_set<repair_hash>& set_diff) {
+                [this] (std::list<repair_row>& rows, repair_hash_set& set_diff) {
             return do_for_each(_working_row_buf, [this, &set_diff, &rows] (const repair_row& r) {
                 if (set_diff.count(r.hash()) > 0) {
                     rows.push_back(r);
@@ -1180,7 +1233,7 @@ private:
     // Give a set of row hashes, return the corresponding rows
     // If needs_all_rows is set, return all the rows in _working_row_buf, ignore the set_diff
     future<std::list<repair_row>>
-    get_row_diff(std::unordered_set<repair_hash> set_diff, needs_all_rows_t needs_all_rows = needs_all_rows_t::no) {
+    get_row_diff(repair_hash_set set_diff, needs_all_rows_t needs_all_rows = needs_all_rows_t::no) {
         if (needs_all_rows) {
             if (!_repair_master || _nr_peer_nodes == 1) {
                 return make_ready_future<std::list<repair_row>>(std::move(_working_row_buf));
@@ -1191,6 +1244,32 @@ private:
         }
     }
 
+    future<> do_apply_rows(std::list<repair_row>&& row_diff, unsigned node_idx, update_working_row_buf update_buf) {
+        return do_with(std::move(row_diff), [this, node_idx, update_buf] (std::list<repair_row>& row_diff) {
+            return with_semaphore(_repair_writer->sem(), 1, [this, node_idx, update_buf, &row_diff] {
+                _repair_writer->create_writer(_db, node_idx);
+                return repeat([this, node_idx, update_buf, &row_diff] () mutable {
+                    if (row_diff.empty()) {
+                        return make_ready_future<stop_iteration>(stop_iteration::yes);
+                    }
+                    repair_row& r = row_diff.front();
+                    if (update_buf) {
+                        _working_row_buf_combined_hash.add(r.hash());
+                    }
+                    // The repair_row here is supposed to have
+                    // mutation_fragment attached because we have stored it in
+                    // to_repair_rows_list above where the repair_row is created.
+                    mutation_fragment mf = std::move(r.get_mutation_fragment());
+                    auto dk_with_hash = r.get_dk_with_hash();
+                    return _repair_writer->do_write(node_idx, std::move(dk_with_hash), std::move(mf)).then([&row_diff] {
+                        row_diff.pop_front();
+                        return make_ready_future<stop_iteration>(stop_iteration::no);
+                    });
+                });
+            });
+        });
+    }
+
     // Give a list of rows, apply the rows to disk and update the _working_row_buf and _peer_row_hash_sets if requested
     // Must run inside a seastar thread
     void apply_rows_on_master_in_thread(repair_rows_on_wire rows, gms::inet_address from, update_working_row_buf update_buf,
@@ -1204,30 +1283,17 @@ private:
         stats().rx_row_nr += row_diff.size();
         stats().rx_row_nr_peer[from] += row_diff.size();
         if (update_buf) {
-            std::list<repair_row> tmp;
-            tmp.swap(_working_row_buf);
             // Both row_diff and _working_row_buf and are ordered, merging
             // two sored list to make sure the combination of row_diff
             // and _working_row_buf are ordered.
-            std::merge(tmp.begin(), tmp.end(), row_diff.begin(), row_diff.end(), std::back_inserter(_working_row_buf),
-                [this] (const repair_row& x, const repair_row& y) { thread::maybe_yield(); return _cmp(x.boundary(), y.boundary()) < 0; });
+            utils::merge_to_gently(_working_row_buf, row_diff,
+                 [this] (const repair_row& x, const repair_row& y) { return _cmp(x.boundary(), y.boundary()) < 0; });
         }
         if (update_hash_set) {
-            _peer_row_hash_sets[node_idx] = boost::copy_range<std::unordered_set<repair_hash>>(row_diff |
+            _peer_row_hash_sets[node_idx] = boost::copy_range<repair_hash_set>(row_diff |
                     boost::adaptors::transformed([] (repair_row& r) { thread::maybe_yield(); return r.hash(); }));
         }
-        _repair_writer.create_writer(_db, node_idx);
-        for (auto& r : row_diff) {
-            if (update_buf) {
-                _working_row_buf_combined_hash.add(r.hash());
-            }
-            // The repair_row here is supposed to have
-            // mutation_fragment attached because we have stored it in
-            // to_repair_rows_list above where the repair_row is created.
-            mutation_fragment mf = std::move(r.get_mutation_fragment());
-            auto dk_with_hash = r.get_dk_with_hash();
-            _repair_writer.do_write(node_idx, std::move(dk_with_hash), std::move(mf)).get();
-        }
+        do_apply_rows(std::move(row_diff), node_idx, update_buf).get();
     }
 
     future<>
@@ -1235,19 +1301,9 @@ private:
         if (rows.empty()) {
             return make_ready_future<>();
         }
-        return to_repair_rows_list(rows).then([this] (std::list<repair_row> row_diff) {
-            return do_with(std::move(row_diff), [this] (std::list<repair_row>& row_diff) {
-                unsigned node_idx = 0;
-                _repair_writer.create_writer(_db, node_idx);
-                return do_for_each(row_diff, [this, node_idx] (repair_row& r) {
-                    // The repair_row here is supposed to have
-                    // mutation_fragment attached because we have stored it in
-                    // to_repair_rows_list above where the repair_row is created.
-                    mutation_fragment mf = std::move(r.get_mutation_fragment());
-                    auto dk_with_hash = r.get_dk_with_hash();
-                    return _repair_writer.do_write(node_idx, std::move(dk_with_hash), std::move(mf));
-                });
-            });
+        return to_repair_rows_list(std::move(rows)).then([this] (std::list<repair_row> row_diff) {
+            unsigned node_idx = 0;
+            return do_apply_rows(std::move(row_diff), node_idx, update_working_row_buf::no);
         });
     }
 
@@ -1326,13 +1382,13 @@ private:
 public:
     // RPC API
     // Return the hashes of the rows in _working_row_buf
-    future<std::unordered_set<repair_hash>>
+    future<repair_hash_set>
     get_full_row_hashes(gms::inet_address remote_node) {
         if (remote_node == _myip) {
             return get_full_row_hashes_handler();
         }
         return netw::get_local_messaging_service().send_repair_get_full_row_hashes(msg_addr(remote_node),
-                _repair_meta_id).then([this, remote_node] (std::unordered_set<repair_hash> hashes) {
+                _repair_meta_id).then([this, remote_node] (repair_hash_set hashes) {
             rlogger.debug("Got full hashes from peer={}, nr_hashes={}", remote_node, hashes.size());
             _metrics.rx_hashes_nr += hashes.size();
             stats().rx_hashes_nr += hashes.size();
@@ -1343,7 +1399,7 @@ public:
 
 private:
     future<> get_full_row_hashes_source_op(
-            lw_shared_ptr<std::unordered_set<repair_hash>> current_hashes,
+            lw_shared_ptr<repair_hash_set> current_hashes,
             gms::inet_address remote_node,
             unsigned node_idx,
             rpc::source<repair_hash_with_cmd>& source) {
@@ -1381,12 +1437,12 @@ private:
     }
 
 public:
-    future<std::unordered_set<repair_hash>>
+    future<repair_hash_set>
     get_full_row_hashes_with_rpc_stream(gms::inet_address remote_node, unsigned node_idx) {
         if (remote_node == _myip) {
             return get_full_row_hashes_handler();
         }
-        auto current_hashes = make_lw_shared<std::unordered_set<repair_hash>>();
+        auto current_hashes = make_lw_shared<repair_hash_set>();
         return _sink_source_for_get_full_row_hashes.get_sink_source(remote_node, node_idx).then(
                 [this, current_hashes, remote_node, node_idx]
                 (rpc::sink<repair_stream_cmd>& sink, rpc::source<repair_hash_with_cmd>& source) mutable {
@@ -1401,7 +1457,7 @@ public:
     }
 
     // RPC handler
-    future<std::unordered_set<repair_hash>>
+    future<repair_hash_set>
     get_full_row_hashes_handler() {
         return with_gate(_gate, [this] {
             return working_row_hashes();
@@ -1541,7 +1597,7 @@ public:
     // RPC API
     // Return rows in the _working_row_buf with hash within the given sef_diff
     // Must run inside a seastar thread
-    void get_row_diff(std::unordered_set<repair_hash> set_diff, needs_all_rows_t needs_all_rows, gms::inet_address remote_node, unsigned node_idx) {
+    void get_row_diff(repair_hash_set set_diff, needs_all_rows_t needs_all_rows, gms::inet_address remote_node, unsigned node_idx) {
         if (needs_all_rows || !set_diff.empty()) {
             if (remote_node == _myip) {
                 return;
@@ -1610,11 +1666,11 @@ private:
     }
 
     future<> get_row_diff_sink_op(
-            std::unordered_set<repair_hash> set_diff,
+            repair_hash_set set_diff,
             needs_all_rows_t needs_all_rows,
             rpc::sink<repair_hash_with_cmd>& sink,
             gms::inet_address remote_node) {
-        return do_with(std::move(set_diff), [needs_all_rows, remote_node, &sink] (std::unordered_set<repair_hash>& set_diff) mutable {
+        return do_with(std::move(set_diff), [needs_all_rows, remote_node, &sink] (repair_hash_set& set_diff) mutable {
             if (inject_rpc_stream_error) {
                 return make_exception_future<>(std::runtime_error("get_row_diff: Inject sender error in sink loop"));
             }
@@ -1641,7 +1697,7 @@ private:
 public:
     // Must run inside a seastar thread
     void get_row_diff_with_rpc_stream(
-            std::unordered_set<repair_hash> set_diff,
+            repair_hash_set set_diff,
             needs_all_rows_t needs_all_rows,
             update_peer_row_hash_sets update_hash_set,
             gms::inet_address remote_node,
@@ -1667,7 +1723,7 @@ public:
     }
 
     // RPC handler
-    future<repair_rows_on_wire> get_row_diff_handler(std::unordered_set<repair_hash> set_diff, needs_all_rows_t needs_all_rows) {
+    future<repair_rows_on_wire> get_row_diff_handler(repair_hash_set set_diff, needs_all_rows_t needs_all_rows) {
         return with_gate(_gate, [this, set_diff = std::move(set_diff), needs_all_rows] () mutable {
             return get_row_diff(std::move(set_diff), needs_all_rows).then([this] (std::list<repair_row> row_diff) {
                 return to_repair_rows_on_wire(std::move(row_diff));
@@ -1677,15 +1733,16 @@ public:
 
     // RPC API
     // Send rows in the _working_row_buf with hash within the given sef_diff
-    future<> put_row_diff(std::unordered_set<repair_hash> set_diff, needs_all_rows_t needs_all_rows, gms::inet_address remote_node) {
+    future<> put_row_diff(repair_hash_set set_diff, needs_all_rows_t needs_all_rows, gms::inet_address remote_node) {
         if (!set_diff.empty()) {
             if (remote_node == _myip) {
                 return make_ready_future<>();
             }
-            auto sz = set_diff.size();
+            size_t sz = set_diff.size();
             return get_row_diff(std::move(set_diff), needs_all_rows).then([this, remote_node, sz] (std::list<repair_row> row_diff) {
                 if (row_diff.size() != sz) {
-                    throw std::runtime_error("row_diff.size() != set_diff.size()");
+                    rlogger.warn("Hash conflict detected, keyspace={}, table={}, range={}, row_diff.size={}, set_diff.size={}. It is recommended to compact the table and rerun repair for the range.",
+                            _schema->ks_name(), _schema->cf_name(), _range, row_diff.size(), sz);
                 }
                 return do_with(std::move(row_diff), [this, remote_node] (std::list<repair_row>& row_diff) {
                     return get_repair_rows_size(row_diff).then([this, remote_node, &row_diff] (size_t row_bytes) mutable {
@@ -1752,17 +1809,18 @@ private:
 
 public:
     future<> put_row_diff_with_rpc_stream(
-            std::unordered_set<repair_hash> set_diff,
+            repair_hash_set set_diff,
             needs_all_rows_t needs_all_rows,
             gms::inet_address remote_node, unsigned node_idx) {
         if (!set_diff.empty()) {
             if (remote_node == _myip) {
                 return make_ready_future<>();
             }
-            auto sz = set_diff.size();
+            size_t sz = set_diff.size();
             return get_row_diff(std::move(set_diff), needs_all_rows).then([this, remote_node, node_idx, sz] (std::list<repair_row> row_diff) {
                 if (row_diff.size() != sz) {
-                    throw std::runtime_error("row_diff.size() != set_diff.size()");
+                    rlogger.warn("Hash conflict detected, keyspace={}, table={}, range={}, row_diff.size={}, set_diff.size={}. It is recommended to compact the table and rerun repair for the range.",
+                            _schema->ks_name(), _schema->cf_name(), _range, row_diff.size(), sz);
                 }
                 return do_with(std::move(row_diff), [this, remote_node, node_idx] (std::list<repair_row>& row_diff) {
                     return get_repair_rows_size(row_diff).then([this, remote_node, node_idx, &row_diff] (size_t row_bytes) mutable {
@@ -1801,7 +1859,7 @@ static future<stop_iteration> repair_get_row_diff_with_rpc_stream_process_op(
         rpc::sink<repair_row_on_wire_with_cmd> sink,
         rpc::source<repair_hash_with_cmd> source,
         bool &error,
-        std::unordered_set<repair_hash>& current_set_diff,
+        repair_hash_set& current_set_diff,
         std::optional<std::tuple<repair_hash_with_cmd>> hash_cmd_opt) {
     repair_hash_with_cmd hash_cmd = std::get<0>(hash_cmd_opt.value());
     rlogger.trace("Got repair_hash_with_cmd from peer={}, hash={}, cmd={}", from, hash_cmd.hash, int(hash_cmd.cmd));
@@ -1814,7 +1872,7 @@ static future<stop_iteration> repair_get_row_diff_with_rpc_stream_process_op(
         }
         bool needs_all_rows = hash_cmd.cmd == repair_stream_cmd::needs_all_rows;
         _metrics.rx_hashes_nr += current_set_diff.size();
-        auto fp = make_foreign(std::make_unique<std::unordered_set<repair_hash>>(std::move(current_set_diff)));
+        auto fp = make_foreign(std::make_unique<repair_hash_set>(std::move(current_set_diff)));
         return smp::submit_to(src_cpu_id % smp::count, [from, repair_meta_id, needs_all_rows, fp = std::move(fp)] {
             auto rm = repair_meta::get_repair_meta(from, repair_meta_id);
             if (fp.get_owner_shard() == this_shard_id()) {
@@ -1892,12 +1950,12 @@ static future<stop_iteration> repair_get_full_row_hashes_with_rpc_stream_process
     if (status == repair_stream_cmd::get_full_row_hashes) {
         return smp::submit_to(src_cpu_id % smp::count, [from, repair_meta_id] {
             auto rm = repair_meta::get_repair_meta(from, repair_meta_id);
-            return rm->get_full_row_hashes_handler().then([] (std::unordered_set<repair_hash> hashes) {
+            return rm->get_full_row_hashes_handler().then([] (repair_hash_set hashes) {
                 _metrics.tx_hashes_nr += hashes.size();
                 return hashes;
             });
-        }).then([sink] (std::unordered_set<repair_hash> hashes) mutable {
-            return do_with(std::move(hashes), [sink] (std::unordered_set<repair_hash>& hashes) mutable {
+        }).then([sink] (repair_hash_set hashes) mutable {
+            return do_with(std::move(hashes), [sink] (repair_hash_set& hashes) mutable {
                 return do_for_each(hashes, [sink] (const repair_hash& hash) mutable {
                     return sink(repair_hash_with_cmd{repair_stream_cmd::hash_data, hash});
                 }).then([sink] () mutable {
@@ -1920,7 +1978,7 @@ static future<> repair_get_row_diff_with_rpc_stream_handler(
         uint32_t repair_meta_id,
         rpc::sink<repair_row_on_wire_with_cmd> sink,
         rpc::source<repair_hash_with_cmd> source) {
-    return do_with(false, std::unordered_set<repair_hash>(), [from, src_cpu_id, repair_meta_id, sink, source] (bool& error, std::unordered_set<repair_hash>& current_set_diff) mutable {
+    return do_with(false, repair_hash_set(), [from, src_cpu_id, repair_meta_id, sink, source] (bool& error, repair_hash_set& current_set_diff) mutable {
         return repeat([from, src_cpu_id, repair_meta_id, sink, source, &error, &current_set_diff] () mutable {
             return source().then([from, src_cpu_id, repair_meta_id, sink, source, &error, &current_set_diff] (std::optional<std::tuple<repair_hash_with_cmd>> hash_cmd_opt) mutable {
                 if (hash_cmd_opt) {
@@ -1936,22 +1994,17 @@ static future<> repair_get_row_diff_with_rpc_stream_handler(
                             current_set_diff,
                             std::move(hash_cmd_opt)).handle_exception([sink, &error] (std::exception_ptr ep) mutable {
                         error = true;
-                        return sink(repair_row_on_wire_with_cmd{repair_stream_cmd::error, repair_row_on_wire()}).then([sink] ()  mutable {
-                            return sink.close();
-                        }).then([sink] {
+                        return sink(repair_row_on_wire_with_cmd{repair_stream_cmd::error, repair_row_on_wire()}).then([] {
                             return make_ready_future<stop_iteration>(stop_iteration::no);
                         });
                     });
                 } else {
-                    if (error) {
-                        return make_ready_future<stop_iteration>(stop_iteration::yes);
-                    }
-                    return sink.close().then([sink] {
-                        return make_ready_future<stop_iteration>(stop_iteration::yes);
-                    });
+                    return make_ready_future<stop_iteration>(stop_iteration::yes);
                 }
             });
         });
+    }).finally([sink] () mutable {
+        return sink.close().finally([sink] { });
     });
 }
 
@@ -1977,22 +2030,17 @@ static future<> repair_put_row_diff_with_rpc_stream_handler(
                             current_rows,
                             std::move(row_opt)).handle_exception([sink, &error] (std::exception_ptr ep) mutable {
                         error = true;
-                        return sink(repair_stream_cmd::error).then([sink] ()  mutable {
-                            return sink.close();
-                        }).then([sink] {
+                        return sink(repair_stream_cmd::error).then([] {
                             return make_ready_future<stop_iteration>(stop_iteration::no);
                         });
                     });
                 } else {
-                    if (error) {
-                        return make_ready_future<stop_iteration>(stop_iteration::yes);
-                    }
-                    return sink.close().then([sink] {
-                        return make_ready_future<stop_iteration>(stop_iteration::yes);
-                    });
+                    return make_ready_future<stop_iteration>(stop_iteration::yes);
                 }
             });
         });
+    }).finally([sink] () mutable {
+        return sink.close().finally([sink] { });
     });
 }
 
@@ -2017,22 +2065,17 @@ static future<> repair_get_full_row_hashes_with_rpc_stream_handler(
                             error,
                             std::move(status_opt)).handle_exception([sink, &error] (std::exception_ptr ep) mutable {
                         error = true;
-                        return sink(repair_hash_with_cmd{repair_stream_cmd::error, repair_hash()}).then([sink] ()  mutable {
-                            return sink.close();
-                        }).then([sink] {
+                        return sink(repair_hash_with_cmd{repair_stream_cmd::error, repair_hash()}).then([] () {
                             return make_ready_future<stop_iteration>(stop_iteration::no);
                         });
                     });
                 } else {
-                    if (error) {
-                        return make_ready_future<stop_iteration>(stop_iteration::yes);
-                    }
-                    return sink.close().then([sink] {
-                        return make_ready_future<stop_iteration>(stop_iteration::yes);
-                    });
+                    return make_ready_future<stop_iteration>(stop_iteration::yes);
                 }
             });
         });
+    }).finally([sink] () mutable {
+        return sink.close().finally([sink] { });
     });
 }
 
@@ -2078,7 +2121,7 @@ future<> repair_init_messaging_service_handler(repair_service& rs, distributed<d
             auto from = cinfo.retrieve_auxiliary<gms::inet_address>("baddr");
             return smp::submit_to(src_cpu_id % smp::count, [from, repair_meta_id] {
                 auto rm = repair_meta::get_repair_meta(from, repair_meta_id);
-                return rm->get_full_row_hashes_handler().then([] (std::unordered_set<repair_hash> hashes) {
+                return rm->get_full_row_hashes_handler().then([] (repair_hash_set hashes) {
                     _metrics.tx_hashes_nr += hashes.size();
                     return hashes;
                 });
@@ -2106,11 +2149,11 @@ future<> repair_init_messaging_service_handler(repair_service& rs, distributed<d
             });
         });
         ms.register_repair_get_row_diff([] (const rpc::client_info& cinfo, uint32_t repair_meta_id,
-                std::unordered_set<repair_hash> set_diff, bool needs_all_rows) {
+                repair_hash_set set_diff, bool needs_all_rows) {
             auto src_cpu_id = cinfo.retrieve_auxiliary<uint32_t>("src_cpu_id");
             auto from = cinfo.retrieve_auxiliary<gms::inet_address>("baddr");
             _metrics.rx_hashes_nr += set_diff.size();
-            auto fp = make_foreign(std::make_unique<std::unordered_set<repair_hash>>(std::move(set_diff)));
+            auto fp = make_foreign(std::make_unique<repair_hash_set>(std::move(set_diff)));
             return smp::submit_to(src_cpu_id % smp::count, [from, repair_meta_id, fp = std::move(fp), needs_all_rows] () mutable {
                 auto rm = repair_meta::get_repair_meta(from, repair_meta_id);
                 if (fp.get_owner_shard() == this_shard_id()) {
@@ -2178,6 +2221,25 @@ future<> repair_init_messaging_service_handler(repair_service& rs, distributed<d
     });
 }
 
+future<> repair_uninit_messaging_service_handler() {
+    return netw::get_messaging_service().invoke_on_all([] (auto& ms) {
+        return when_all_succeed(
+            ms.unregister_repair_get_row_diff_with_rpc_stream(),
+            ms.unregister_repair_put_row_diff_with_rpc_stream(),
+            ms.unregister_repair_get_full_row_hashes_with_rpc_stream(),
+            ms.unregister_repair_get_full_row_hashes(),
+            ms.unregister_repair_get_combined_row_hash(),
+            ms.unregister_repair_get_sync_boundary(),
+            ms.unregister_repair_get_row_diff(),
+            ms.unregister_repair_put_row_diff(),
+            ms.unregister_repair_row_level_start(),
+            ms.unregister_repair_row_level_stop(),
+            ms.unregister_repair_get_estimated_partitions(),
+            ms.unregister_repair_set_estimated_partitions(),
+            ms.unregister_repair_get_diff_algorithms()).discard_result();
+    });
+}
+
 class row_level_repair {
     repair_info& _ri;
     sstring _cf_name;
@@ -2407,7 +2469,7 @@ private:
             // sequentially because the rows from repair follower 1 to
             // repair master might reduce the amount of missing data
             // between repair master and repair follower 2.
-            std::unordered_set<repair_hash> set_diff = repair_meta::get_set_diff(master.peer_row_hash_sets(node_idx), master.working_row_hashes().get0());
+            repair_hash_set set_diff = repair_meta::get_set_diff(master.peer_row_hash_sets(node_idx), master.working_row_hashes().get0());
             // Request missing sets from peer node
             rlogger.debug("Before get_row_diff to node {}, local={}, peer={}, set_diff={}",
                     node, master.working_row_hashes().get0().size(), master.peer_row_hash_sets(node_idx).size(), set_diff.size());
@@ -2430,9 +2492,9 @@ private:
         // So we can figure out which rows peer node are missing and send the missing rows to them
         check_in_shutdown();
         _ri.check_in_abort();
-        std::unordered_set<repair_hash> local_row_hash_sets = master.working_row_hashes().get0();
+        repair_hash_set local_row_hash_sets = master.working_row_hashes().get0();
         auto sz = _all_live_peer_nodes.size();
-        std::vector<std::unordered_set<repair_hash>> set_diffs(sz);
+        std::vector<repair_hash_set> set_diffs(sz);
         for (size_t idx : boost::irange(size_t(0), sz)) {
             set_diffs[idx] = repair_meta::get_set_diff(local_row_hash_sets, master.peer_row_hash_sets(idx));
         }

repair/row_level.hh

@@ -45,6 +45,7 @@ private:
 };
 
 future<> repair_init_messaging_service_handler(repair_service& rs, distributed<db::system_distributed_keyspace>& sys_dist_ks, distributed<db::view::view_update_generator>& view_update_generator);
+future<> repair_uninit_messaging_service_handler();
 
 class repair_info;
 

row_cache.cc

@@ -528,8 +528,12 @@ public:
         return _reader.move_to_next_partition(timeout).then([this] (auto&& mfopt) mutable {
             {
                 if (!mfopt) {
-                    this->handle_end_of_stream();
-                    return make_ready_future<flat_mutation_reader_opt, mutation_fragment_opt>(std::nullopt, std::nullopt);
+                    return _cache._read_section(_cache._tracker.region(), [&] {
+                        return with_linearized_managed_bytes([&] {
+                            this->handle_end_of_stream();
+                            return make_ready_future<flat_mutation_reader_opt, mutation_fragment_opt>(std::nullopt, std::nullopt);
+                        });
+                    });
                 }
                 _cache.on_partition_miss();
                 const partition_start& ps = mfopt->as_partition_start();
@@ -952,13 +956,15 @@ future<> row_cache::do_update(external_updater eu, memtable& m, Updater updater)
                         // expensive and we need to amortize it somehow.
                         do {
                           STAP_PROBE(scylla, row_cache_update_partition_start);
-                          with_linearized_managed_bytes([&] {
+                          {
                             if (!update) {
                                 _update_section(_tracker.region(), [&] {
+                                  with_linearized_managed_bytes([&] {
                                     memtable_entry& mem_e = *m.partitions.begin();
                                     size_entry = mem_e.size_in_allocator_without_rows(_tracker.allocator());
                                     auto cache_i = _partitions.lower_bound(mem_e.key(), cmp);
                                     update = updater(_update_section, cache_i, mem_e, is_present, real_dirty_acc);
+                                  });
                                 });
                             }
                             // We use cooperative deferring instead of futures so that
@@ -970,14 +976,16 @@ future<> row_cache::do_update(external_updater eu, memtable& m, Updater updater)
                             update = {};
                             real_dirty_acc.unpin_memory(size_entry);
                             _update_section(_tracker.region(), [&] {
+                              with_linearized_managed_bytes([&] {
                                 auto i = m.partitions.begin();
                                 memtable_entry& mem_e = *i;
                                 m.partitions.erase(i);
                                 mem_e.partition().evict(_tracker.memtable_cleaner());
                                 current_allocator().destroy(&mem_e);
+                              });
                             });
                             ++partition_count;
-                          });
+                          }
                           STAP_PROBE(scylla, row_cache_update_partition_end);
                         } while (!m.partitions.empty() && !need_preempt());
                         with_allocator(standard_allocator(), [&] {
@@ -1124,8 +1132,8 @@ future<> row_cache::invalidate(external_updater eu, dht::partition_range_vector&
                 seastar::thread::maybe_yield();
 
                 while (true) {
-                    auto done = with_linearized_managed_bytes([&] {
-                        return _update_section(_tracker.region(), [&] {
+                    auto done = _update_section(_tracker.region(), [&] {
+                        return with_linearized_managed_bytes([&] {
                             auto cmp = cache_entry::compare(_schema);
                             auto it = _partitions.lower_bound(*_prev_snapshot_pos, cmp);
                             auto end = _partitions.lower_bound(dht::ring_position_view::for_range_end(range), cmp);

schema.cc

@@ -43,6 +43,8 @@
 
 constexpr int32_t schema::NAME_LENGTH;
 
+extern logging::logger dblog;
+
 sstring to_sstring(column_kind k) {
     switch (k) {
     case column_kind::partition_key:  return "PARTITION_KEY";
@@ -592,11 +594,15 @@ schema::get_column_definition(const bytes& name) const {
 
 const column_definition&
 schema::column_at(column_kind kind, column_id id) const {
-    return _raw._columns.at(column_offset(kind) + id);
+    return column_at(static_cast<ordinal_column_id>(column_offset(kind) + id));
 }
 
 const column_definition&
 schema::column_at(ordinal_column_id ordinal_id) const {
+    if (size_t(ordinal_id) >= _raw._columns.size()) {
+        on_internal_error(dblog, format("{}.{}@{}: column id {:d} >= {:d}",
+            ks_name(), cf_name(), version(), size_t(ordinal_id), _raw._columns.size()));
+    }
     return _raw._columns.at(static_cast<column_count_type>(ordinal_id));
 }
 

scripts/create-relocatable-package.py

@@ -79,7 +79,8 @@ executables = ['build/{}/scylla'.format(args.mode),
                '/usr/sbin/ethtool',
                '/usr/bin/netstat',
                '/usr/bin/hwloc-distrib',
-               '/usr/bin/hwloc-calc']
+               '/usr/bin/hwloc-calc',
+               '/usr/bin/lsblk']
 
 output = args.dest
 

scylla-gdb.py

@@ -597,7 +597,7 @@ def current_shard():
 
 
 def find_db(shard=None):
-    if not shard:
+    if shard is None:
         shard = current_shard()
     return gdb.parse_and_eval('::debug::db')['_instances']['_M_impl']['_M_start'][shard]['service']['_p']