Commit Graph

833 Commits

Author SHA1 Message Date
Patryk Jędrzejczak
d5c205194b Merge 'topology: Make removenode use left_token_ring state for global barrier' from Emil Maskovsky
Make the removenode operation go through the `left_token_ring` state, similar to decommission. This ensures that when removenode completes, all nodes in the cluster are aware of the topology change through a global token metadata barrier.

Previously, removenode would skip the `left_token_ring` state and go directly from `write_both_read_new` to `left` state. This meant that when the operation completed, some nodes might not yet know about the topology change, potentially causing issues with subsequent data plane requests.

Key changes:
- Both decommission and removenode now transition to `left_token_ring` state in the `write_both_read_new` handler
- In `left_token_ring` state, only decommissioning nodes receive the shutdown RPC (removed nodes are already dead)
- Updated documentation to reflect that both operations use this state

This change improves consistency guarantees for removenode operations by ensuring cluster-wide awareness before completion.

The change is protected by "REMOVENODE_WITH_LEFT_TOKEN_RING" feature flag to also support mixed clusters during e.g. upgrade.

Fixes:  scylladb/scylladb#25530

No backport: This fixes and issue found in tests. It can theoretically happen in production too, but wasn't reported in any customer issue, so a backport is not needed.

Closes scylladb/scylladb#26931

* https://github.com/scylladb/scylladb:
  topology: make removenode use left_token_ring state for global barrier
  topology: allow removing nodes not having tokens
  features: add feature flag for removenode via left token ring
2025-12-18 09:34:38 +01:00
Emil Maskovsky
9431826c52 topology: allow removing nodes not having tokens
For the changes to go through the left_token_ring state when
REMOVENODE_WITH_LEFT_TOKEN_RING feature is enabled, we need to allow
removing nodes to not have any tokens (similarly to decommissioning
nodes, which use the same sequence of states).

This means the tests also need to change to allow for this new behavior
- it can temporarily happen that a removing node has no tokens but is
still part of Raft group 0 (so there may be a temporary mismatch between
the token ring and group 0 membership).

Therefore, the `check_token_ring_and_group0_consistency` function is
replaced by `wait_for_token_ring_and_group0_consistency`, which waits
up to 30 seconds for consistency to be reached.
2025-12-17 13:31:11 +01:00
Tomasz Grabiec
c077283352 Merge 'service: support conversion of tablet keyspaces to rack-list using ALTER KEYSPACE' from Aleksandra Martyniuk
If a keyspace has a numeric replication factor in a DC and rf < #racks,
then the replicas of tablets in this keyspace can be distributed among
all racks in the DC (different for each tablet). With rack list, we need all
tablet replicas to be placed on the same racks. Hence, the conversion
requires tablet co-location.

After this series, the conversion can be done using ALTER KEYSPACE
statement. The statement that does this conversion in any DC is not
allowed to change a rf in any DC. So, if we have dc1 and dc2 with 3 racks
each and a keyspace ks then with a single ALTER KEYSPACE we can do:
- {dc1 : 2} -> {dc1 : [r1, r2]};
- {dc1 : 2, dc2: 2} ->  {dc1 : [r1, r2], dc2: [r2,r3]};
- {dc1 : 2, dc2: 2} -> {dc1 : [r1, r2], dc2: 2}
- {dc1 : 2} -> {dc1 : 2, dc2 : [r1]}
But we cannot do:
- {dc1 : 2} -> {dc1 : [r1, r2, r3]};
- {dc1 : 1, dc2 : [r1, r2] → dc1: [r1], dc2: [r1].

In order to do the co-locations rf change request is paused. Tablet
load balancer examines the paused rf change requests and schedules
necessary tablet migrations. During the process of co-location, no other
cross-rack migration is allowed.

Load balancer checks whether any paused rf change request is
ready to be resumed. If so, it puts the request back to global topology
request queue.

While an rf change request for a keyspace is running, any other rf change
of this keyspace will fail.

Fixes: #26398.

New feature, no backport

Closes scylladb/scylladb#27279

* github.com:scylladb/scylladb:
  test: add est_rack_list_conversion_with_two_replicas_in_rack
  test: test creating tablet_rack_list_colocation_plan
  test: add test_numeric_rf_to_rack_list_conversion test
  tasks: service: add global_topology_request_virtual_task
  cql3: statements: allow altering from numeric rf to rack list
  service: topology_coordinator: pause keyspace_rf_change request
  service: implement make_rack_list_colocation_plan
  service: add tablet_rack_list_colocation_plan
  cql3: reject concurrent alter of the same keyspace
  test: check paused rf change requests persistence
  db: service: add paused_rf_change_requests to system.topology
  service: pass topology and system_keyspace to load_balancer ctor
  service: tablet_allocator: extract load updates
  service: tablet_allocator: extract ensure_node
  tasks, system_keyspace: Introduce get_topology_request_entry_opt()
  node_ops: Drop get_pending_ids()
  node_ops: Drop redundant get_status_helper()
2025-12-17 10:05:06 +01:00
Aleksandra Martyniuk
9039dfa4a5 tasks: service: add global_topology_request_virtual_task
Add a service::topo::global_topology_request_virtual_task, which
covers the replication factor changes.

Currently, the global_topology_request_virtual_task can be aborted
only if it is paused.

The progress of the rf change isn't counted.
2025-12-16 13:31:22 +01:00
Aleksandra Martyniuk
08e5f35527 db: service: add paused_rf_change_requests to system.topology
In the following changes, we allow to alter from numeric rf to rack list.
Before the alter, two tablets of the same keyspace can have replicas
on different racks. To switch to rack list, we need to co-locate
the replicas. It will be achieved by pausing the keyspace_rf_change
and scheduling migrations.

We need to persist the ids of requests that are paused. A new column -
paused_rf_change_requests is added to system.topology table.

In this commit no data is kept in the new column.
2025-12-16 13:25:38 +01:00
Tomasz Grabiec
71e6ef90f4 tasks, system_keyspace: Introduce get_topology_request_entry_opt()
It's a cleanup. Better to return std::nullopt than faking an entry
with an id when require_entry == false.
2025-12-16 13:25:34 +01:00
Patryk Jędrzejczak
73db5c94de Merge 'db: api: service: introduce system.client_routes table and related API endpoints' from Andrzej Jackowski
`system.client_routes` is a system table that sets the target address and ports for each `host_id`, for one or more connection (e.g., Private Link) represented by `connection_id`. Cloud will write the table via REST, and drivers will read it via CQL to override values obtained from `system.local` and `system.peers`.

This patch series contains:
 - Introduction of `CLIENT_ROUTES` feature flag.
 - Implementation of raft-based `system.client_routes` table
 - Implementation of `v2/client-routes` POST/DELETE/GET endpoints
 - Implementation of new `CLIENT_ROUTES_CHANGE` event that is sent to drivers when `system.client_routes` is changed
 - New tests that verifies the aforementioned features

Ref: scylladb/scylla-enterprise#5699

For now, no automatic backport. However, the changes are planned to be release on `2025.4` either as a backport or a private build.

Closes scylladb/scylladb#27323

* https://github.com/scylladb/scylladb:
  docs: describe CLIENT_ROUTES_CHANGE extension
  test: add test for CLIENT_ROUTES event
  service: transport: add CLIENT_ROUTES_CHANGE event
  test: add cluster tests for client routes
  test: add API tests for client_routes endpoints
  test: add `timeout` parameter to `delete` in RESTClient
  test: allow json_body in send
  api: implement client_routes endpoints
  api: add client_routes.json
  service: main: add client_routes_service
  db: add system.client_routes table
  gms: add CLIENT_ROUTES feature
2025-12-16 10:38:27 +01:00
Andrzej Jackowski
8dde70d04c db: add system.client_routes table
Introduce `system.client_routes`, a system table that sets the target
address and ports for each `host_id`, for one or more connections
(e.g., Private Link) represented by `connection_id`. Cloud will write
the table via REST, and drivers will read it via CQL to override
values obtained from `system.local` and `system.peers`.

The table is Raft-managed to provide consistent replication across
nodes.

Schema overview: each row is identified by `(connection_id, host_id)`
and describes where clients should connect: `address` and one or more of
`port`, `tls_port`, `alternator_port`, `alternator_https_port`.
`host_id` is a UUID (just as in ScyllaDB) but `connection_id` can be
any string to accept formats of all cloud providers. `address` is
also a regular string because it can represent either an IP address or
a domain. Ports are optional in the sense that at least one of
the four must be provided.

Ref: scylladb/scylla-enterprise#5699
2025-12-15 13:08:05 +01:00
Pavel Emelyanov
3f7ee3ce5d Merge 'batchlog: make replay (flush) faster' from Botond Dénes
The batchlog table contains an entry for each logged batch that is processed by the local node as coordinator. These entries are typically very short lived, they are inserted when the batch is processed and deleted immediately after the batch is successfully applied.
When a table has `tombstone_gc = {'mode': 'repair'}` enabled, every repair has to flush all hints and batchlogs, so that we can be certain that there is no live data in any of these, older than the last repair. Since batches can contain member queries from any number of tables, the whole batchlog has to be flushed, even if repair-mode tombstone-gc is enabled for a single table.

Flushing the batchlog table happens by doing a batchlog replay. This involves reading the entire content of this table, and attempting to replay+delete any live entries (that are old enough to be replayed).  Under normal operating circumstances, 99%+ of the content of the batchlog table is partition tombstones.  Because of this, scanning the content of this table has to process thousands to millions of tombstones. This was observed to require up to 20 minutes to finish, causing repairs to slow down to a crawl, as the batchlog-flush has to be repeated at the end of the repair of each token-range.

When trying to address this problem, the first idea was that we should expedite the garbage-collection of these accumulated tombstones. This experiment failed, see https://github.com/scylladb/scylladb/pull/23752. The commitlog proved to be an impossible to bypass barrier, preventing quick garbage-collection of tombstones. So long as a single commit-log segment is alive, holding content from the batchlog table, all tombstones written after are blocked from GC.
The second approach, represented by this PR, is to not rely in tombstone GC to reduce the tombstone amount. Instead restructure the table such that a single higher-order tombstone can be used to shadow and allow for the eviction of the myriads of individual batchlog entry tombstones. This is realized by reorganizing the batchlog table such that individual batches are rows, not partitions.
This new schema is introduced by the new `system.batchlog_v2` table, introduced by this PR:

    CREATE TABLE system.batchlog_v2 (
        version int,
        stage int,
        shard int,
        written_at timestamp,
        id uuid,
        data blob,
        PRIMARY KEY ((version, stage, shard), written_at, id));

The new schema organization has the following goals:
1) Make post-replay batchlog cleanup possible with a simple range-tombstone. This allows dropping the individual dead batchlog entries, as they are shadowed by a higher level tombstone. This enables dropping tombstones without tombstone GC.
2) To make the above possible, introduce the stage key component: batchlog entries that fail the first replay attempt, are moved to the failed_replay stage, so the initial stage can be cleaned up safely.
3) Spread out the data among Scylla shards, via the batchlog shard column.
4) Make batchlog entries ordered by the batchlog create time (id). This allows for selecting batchlogs to replay, without post-filtering of batchlogs that are too young to be replayed.

Fixes: https://github.com/scylladb/scylladb/issues/23358

This is an improvement, normally not a backport-candidate. We might override this and backport to allow wider use of `tombstone_gc: {'mode': 'repair'}`.

Closes scylladb/scylladb#26671

* github.com:scylladb/scylladb:
  db/config: change batchlog_replay_cleanup_after_replays default to 1
  test/boost/batchlog_manager_test: add test for batchlog cleanup
  replica/mutation_dump: always set position weight for clustering positions
  service/storage_proxy: s/batch_replay_throw/storage_proxy_fail_replay_batch/
  test/lib: introduce error_injection.hh
  utils/error_injection: add debug log to disable() and disable_all()
  test/lib/cql_test_env: forward config to batchlog
  test/lib/cql_test_env: add batch type to execute_batch()
  test/lib/cql_assertions: add with_size(predicate) overload
  test/lib/cql_assertions: add source location to fail messages
  test/lib/cql_assertions: columns_assertions: add assert_for_columns_of_each_row()
  test/lib/cql_assertions: rows_assertions::assert_for_columns_of_row(): add index bound check
  test/lib/cql_assertions: columns_assertions: add T* with_typed_column() overload
  db/batchlog_manager: config: s/write_timeout/reply_timeot/
  db,service: switch to system.batchlog_v2
  db/system_keyspace: introduce system.batchlog_v2
  service,db: extract generation of batchlog delete mutation
  service,db: extract get_batchlog_mutation_for() from storage-proxy
  db/batchlog_manager: only consider propagation delay with tombstone-gc=repair
  db/batchlog_manager: don't drop entire batch if one mutations' table was dropped
  data_dictionary: table: add get_truncation_time()
  db/batchlog_manager: batch(): replace map_reduce() with simple loop
  db/batchlog_manager: finish coroutinizing replay_all_failed_batches
  db/batchlog_manager: improve replayAllFailedBatches logs
2025-12-15 15:05:19 +03:00
Avi Kivity
24264e24bb Revert "repair: Add tablet repair progress report support"
This reverts commit faad0167d7. It causes
a regression in

test_two_tablets_concurrent_repair_and_migration_repair_writer_level

in debug mode (with ~5%-10% probability).

Fixes #27510.

Closes scylladb/scylladb#27560
2025-12-11 12:18:11 +02:00
Asias He
faad0167d7 repair: Add tablet repair progress report support
This patch adds tablet repair progress report support so that the user
could use the /task_manager/task_status API to query the progress.

In order to support this, a new system table is introduced to record the
user request related info, i.e, start of the request and end of the
request.

The progress is accurate when tablet split or merge happens in the
middle of the request, since the tokens of the tablet are recorded when
the request is started and when repair of each tablet is finished. The
original tablet repair is considered as finished when the finished
ranges cover the original tablet token ranges.

After this patch, the /task_manager/task_status API will report correct
progress_total and progress_completed.

Fixes #22564
Fixes #26896

Closes scylladb/scylladb#26924
2025-12-08 13:35:19 +02:00
Tomasz Grabiec
d4014b7970 Drop legacy schema support
We switched to using v3 schema tables (in system_schema keyspace) in
2017, in 9eb91bc30b.

So no system should have the old schema any more.

No need to run legacy_schema_migrator on boot.

Closes scylladb/scylladb#27420
2025-12-07 00:09:13 +02:00
Botond Dénes
ee851266be db/system_keyspace: introduce system.batchlog_v2
Rearranges the system.batchlog schema as follows:

    CREATE TABLE system.batchlog_v2 (
        version int,
        stage int,
        shard int,
        written_at timestamp,
        id uuid,
        data blob,
        PRIMARY KEY ((version, stage, shard), written_at, id));

With the following goals:
1) Make post-replay batchlog cleanup possible with a simple
   range-tombstone. This allows dropping the individual dead batchlog
   entries, as they are shadowed by a higher level tombstone. This
   enables dropping tombstones without tombstone GC.
2) To make the above possible, introduce the stage key component:
   batchlog entries that fail the first replay attempt, are moved to the
   failed_replay stage, so the initial stage can be cleaned up safely.
3) Spread out the data among Scylla shards, via the batchlog shard
   column.
4) Make batchlog entries ordered by the batchlog create time (id). This
   allows for selecting batchlogs to replay, without post-filtering of
   batchlogs that are too young to be replayed.
2025-12-02 14:21:25 +02:00
Michał Jadwiszczak
24d69b4005 db/view/view_building_state: replace task's state with aborted flag
After previous commits, we can drop entire task's state and replace it
with single boolean flag, which determines if a task was aborted.

Once a task was aborted, it cannot get resurrected to a normal state.
2025-11-25 12:14:04 +01:00
Gautam Menghani
939fcc0603 db/system_keyspace: Remove the FIXME related to caching of large tables
Remove the FIXME comment for re-enabling caching of the large tables
since the tables are used infrequently [1].

[1] : github.com/scylladb/scylladb/pull/26789#issuecomment-3477540364

Fixes #26032

Signed-off-by: Gautam Menghani <gautam.opensource@gmail.com>

Closes scylladb/scylladb#26789
2025-11-21 12:34:34 +02:00
Petr Gusev
82da83d0e5 topology_state_machine: add excluded_tablet_nodes field
The topology_coordinator::is_excluded() creates a temporary hash
map for each call. This is probably not a performance problem since
left_nodes_rs contains only those left nodes that are referenced
from tablet replicas, this happens temporarily while e.g. a replaced
node is being rebuilt. On the other hand, why not just have a
dedicated field in the topology_state_machine, then this code wouldn't
look suspicious.
2025-11-12 12:27:43 +01:00
Michael Litvak
e7dbccd59e cdc: use chunked_vector instead of vector for stream ids
use utils::chunked_vector instead of std::vector to store cdc stream
sets for tablets.

a cdc stream set usually represents all streams for a specific table and
timestamp, and has a stream id per each tablet of the table. each stream
id is represented by 16 bytes. thus the vector could require quite large
contiguous allocations for a table that has many tablets. change it to
chunked_vector to avoid large contiguous allocations.

Fixes scylladb/scylladb#26791

Closes scylladb/scylladb#26792
2025-10-31 13:02:34 +01:00
Michael Litvak
8743422241 cdc: improve cdc metadata loading
when loading CDC streams metadata for tablets from the tables, read only
new entries from the history table instead of reading all entries. This
improves the CDC metadata reloading, making it more efficient and
predictable.

the CDC metadata is loaded as part of group0 reload whenever the
internal CDC tables are modified. on tablet split / merge, we create a
new CDC timestamp and streams by writing them to the cdc_streams_history
table by group0 operation, and when it's applied we reload the in-memory
CDC streams map by reading from the tables and constructing the updated map.

Previously, on every update, we would read the entire
cdc_streams_history entries for the changed table, constructing all its
streams and creating a new map from scratch.

We improve this now by reading only new entries from cdc_streams_history
and append them to the existing map. we can do this because we only
append new entries to cdc_streams_history with higher timestamp than all
previous entries.

This makes this reloading more efficient and predictable, because
previously we would read a number of entries that depends on the number
of tablets splits and merges, which increases over time and is
unbounded, whereas now we read only a single stream set on each update.

Fixes scylladb/scylladb#26732
2025-10-28 08:54:09 +01:00
Andrzej Jackowski
8953f96609 system_keyspace: add service_level_driver_created
This commit extends sytem.scylla_local table with an additional
key/value pair that can be used later in this patch series to
keep an information that `sl:driver` was already created. The purpose
of storing this information is to ensure that `sl:driver` is
not recreated after being intentionally removed.

A new mutation is included in `register_raft_pull_snapshot` to keep
`service_level_driver_created` in state machine shapshot, which is
required for proper propagation of the value when a new node is added
to the cluster.

Refs: scylladb/scylladb#24411
2025-10-08 08:24:23 +02:00
Nadav Har'El
926089746b message: move RPC compression from utils/ to message/
The directory utils/ is supposed to contain general-purpose utility
classes and functions, which are either already used across the project,
or are designed to be used across the project.

This patch moves 8 files out of utils/:

    utils/advanced_rpc_compressor.hh
    utils/advanced_rpc_compressor.cc
    utils/advanced_rpc_compressor_protocol.hh
    utils/stream_compressor.hh
    utils/stream_compressor.cc
    utils/dict_trainer.cc
    utils/dict_trainer.hh
    utils/shared_dict.hh

These 8 files together implement the compression feature of RPC.
None of them are used by any other Scylla component (e.g., sstables have
a different compression), or are ready to be used by another component,
so this patch moves all of them into message/, where RPC is implemented.

Theoretically, we may want in the future to use this cluster of classes
for some other component, but even then, we shouldn't just have these
files individually in utils/ - these are not useful stand-alone
utilities. One cannot use "shared_dict.hh" assuming it is some sort of
general-purpose shared hash table or something - it is completely
specific to compression and zstd, and specifically to its use in those
other classes.

Beyond moving these 8 files, this patch also contains changes to:
1. Fix includes to the 5 moved header files (.hh).
2. Fix configure.py, utils/CMakeLists.txt and message/CMakeLists.txt
   for the three moved source files (.cc).
3. In the moved files, change from the "utils::" namespace, to the
   "netw::" namespace used by RPC. Also needed to change a bunch
   of callers for the new namespace. Also, had to add "utils::"
   explicitly in several places which previously assumed the
   current namespace is "utils::".

Signed-off-by: Nadav Har'El <nyh@scylladb.com>

Closes scylladb/scylladb#25149
2025-09-30 17:03:09 +03:00
Botond Dénes
86ed627fc4 compaction: move code to namespace compaction
The namespace usage in this directory is very inconsistent, with files
and classes scattered in:
* global namespace
* namespace compaction
* namespace sstables

With cases, where all three used in the same file. This code used to
live in sstables/ and some of it still retains namespace sstables as a
heritage of that time. The mismatch between the dir (future module) and
the namespace used is confusing, so finish the migration and move all
code in compaction/ to namespace compaction too.

This patch, although large, is mechanic and only the following kind of
changes are made:
* replace namespace sstable {} with namespace compaction {}
* add namespace compaction {}
* drop/add sstables::
* drop/add compaction::
* move around forward-declarations so they are in the correct namespace
  context

This refactoring revealed some awkward leftover coupling between
sstables and compaction, in sstables/sstable_set.cc, where the
make_sstable_set() methods of compaction strategies are implemented.
2025-09-25 15:03:56 +03:00
Ernest Zaslavsky
5ba5aec1f8 treewide: Move mutation related files to a mutation directory
As requested in #22104, moved the files and fixed other includes and build system.

Moved files:
 - combine.hh
 - collection_mutation.hh
 - collection_mutation.cc
 - converting_mutation_partition_applier.hh
 - converting_mutation_partition_applier.cc
 - counters.hh
 - counters.cc
 - timestamp.hh

Fixes: #22104

This is a cleanup, no need to backport

Closes scylladb/scylladb#25085
2025-09-24 13:23:38 +03:00
Avi Kivity
1258e7c165 Revert "Merge 'transport: service_level_controller: create and use driver service level' from Andrzej Jackowski"
This reverts commit fe7e63f109, reversing
changes made to b5f3f2f4c5. It is causing
test.py failures around cqlpy.

Fixes #26163

Closes scylladb/scylladb#26174
2025-09-22 09:32:46 +03:00
Michael Litvak
6043409c31 view_builder: register view on all shards atomically
When the view builder starts to build a new view, each shard registers
itself by writing the shard id and current token to the
scylla_views_builds_in_progress table.

Previously, this happened independently by each shard. We change it now
to register all shards "atomically" - when a shard registers itself, it
also registers all other shards with an empty status, if they aren't
registered yet. This ensures that we don't have a partial state in the
table where only some of the shards are registered, but we always have a
status for all shards.

The reason we want to register all shards atomically is that if it
happens that only some of the shards were registered, then we restart
and load the status from table, this doesn't work well for multiple
reasons.

One example is that to know how many shards we had previously, we take
the maximum shard id we see in the table. If it's different than the
current shard count, we will execute the reshard code. But of course, if
the last shard is missing from the table because it didn't register
itself, this calculation will be wrong, and we can't know the previous
number of shards.

This is a problem because suppose we have two shards, and shard 0
finished building the view but shard 1 didn't start. When we come up, we
will think that previously we had only a single shard and it completed
building everything, when in fact we built only half the view
approximately. The problem is that we don't have enough information in
the tables to know that.

There are additional problems related to reshard. In the reshard
function, whether it is executed because we actually do node reshard or
because we calculated the wrong number of previous shards, if the status
of some shard is missing then the calculation of new ranges will be
wrong. When some shard didn't make progress we should start building the
view from scratch. However, this doesn't happen if we don't have a
status for the shard, because the code looks only for shards that have a
status. In effect, this shard is considered complete even though it
didn't start. This could cause the view building to get stuck or
complete without building all tokens ranges.

By registering all shards atomically, this should solve the above
problems because we will always have statuses for all shards.

Fixes scylladb/scylladb#22989
2025-09-21 10:39:05 +02:00
Pavel Emelyanov
a1ea553fe1 code: Replace distributed<> with sharded<>
The latter is recommended in seastar, and the former was left as
compatibility alias. Latest seastar explicitly marks it as deprecated so
once the submodule is updated, compilation logs will explode.

Most of the patch is generated with

    for f in $(git grep -l '\<distributed<[A-Za-z0-9:_]*>') ; do sed -e 's/\<distributed<\([A-Za-z0-9:_]*\)>/sharded<\1>/g' -i $f; done
    for f in $(git grep -l distributed.hh); do sed -e 's/distributed.hh/sharded.hh/' -i $f ; done

and a small manual change in test/perf/perf.hh

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

Closes scylladb/scylladb#26136
2025-09-19 12:22:51 +02:00
Avi Kivity
fe7e63f109 Merge 'transport: service_level_controller: create and use driver service level' from Andrzej Jackowski
This patch series:
 - Increases the number of allowed scheduling groups to allow creation of `sl:driver`
 - Implements `create_driver_service_level` that creates `sl:driver` with shares=200 if it wasn't already created
 - Implements creation of `sl:driver` for new systems and tests in `raft_initialize_discovery_leader`
 - Modifies `topology_coordinator` to use  create `sl:driver` after upgrades.
 - Implements using `sl:driver` for new connections in `transport/server`
 - Adds to `transport/server` recognition of driver's control connections and forcing them to keep using `sl:driver`.
 - Adds tests to verify the new functionality
 - Modifies existing tests to let them pass after `sl:driver` is added
 - Modifies the documentation to contain new `sl:driver`

The changes were evaluated by a test with the following scenario ([test_connections-sl-driver.py](https://github.com/user-attachments/files/22021273/test_connections-sl-driver.py)):
 - Start ScyllaDB with one node
 - Create 1000 keyspaces, 1 table in each keyspace
 - Start `cassandra-stress` (`-rate threads=50  -mode native cql3`)
 - Run connection storm with 1000 session (100 python processes, 10 sessions each)

The maximum latency during connection storm dropped **from 224.94ms to 41.43ms** (those numbers are average from 20 test executions, were max latency was in [140ms, 361ms] before change and [31.4ms, 61.5ms] after).

The snippet of cassandra-stress output from the moment of connection storm:
Before:
```
type       total ops,    op/s,    pk/s,   row/s,    mean,     med,     .95,     .99,    .999,     max,   time,   stderr, errors,  gc: #,  max ms,  sum ms,  sdv ms,      mb
...
total,        789206,   85887,   85887,   85887,     0.6,     0.3,     2.0,     2.0,     2.5,     5.0,    9.0,  0.09679,      0,      0,       0,       0,       0,       0
total,        909322,  120116,  120116,  120116,     0.4,     0.2,     1.9,     2.0,     2.1,     3.1,   10.0,  0.09053,      0,      0,       0,       0,       0,       0
total,        964392,   55070,   55070,   55070,     0.9,     0.4,     2.0,     4.5,     7.7,    18.9,   11.0,  0.09203,      0,      0,       0,       0,       0,       0
total,        975705,   11313,   11313,   11313,     4.4,     3.5,     6.5,    24.5,    82.7,    83.0,   12.0,  0.11713,      0,      0,       0,       0,       0,       0
total,        987548,   11843,   11843,   11843,     4.2,     3.5,     6.5,    33.7,    48.6,    51.5,   13.0,  0.13366,      0,      0,       0,       0,       0,       0
total,        995422,    7874,    7874,    7874,     6.3,     4.0,     7.7,    85.6,   112.9,   113.5,   14.0,  0.14753,      0,      0,       0,       0,       0,       0
total,       1007228,   11806,   11806,   11806,     4.3,     3.5,     6.5,    29.1,    43.8,    87.1,   15.0,  0.15598,      0,      0,       0,       0,       0,       0
total,       1012840,    5612,    5612,    5612,     8.2,     5.0,    11.5,   121.8,   166.6,   170.1,   16.0,  0.16535,      0,      0,       0,       0,       0,       0
total,       1016186,    3346,    3346,    3346,    13.4,     7.4,    20.1,   204.9,   207.6,   210.4,   17.0,  0.17405,      0,      0,       0,       0,       0,       0
total,       1025462,    9276,    9276,    9276,     6.3,     3.9,     9.6,    74.6,   206.8,   210.0,   18.0,  0.17800,      0,      0,       0,       0,       0,       0
total,       1035979,   10517,   10517,   10517,     4.8,     3.5,     6.7,    38.5,    82.6,    83.0,   19.0,  0.18120,      0,      0,       0,       0,       0,       0
total,       1047488,   11509,   11509,   11509,     4.3,     3.5,     6.0,    32.6,    72.3,    74.0,   20.0,  0.18334,      0,      0,       0,       0,       0,       0
total,       1077456,   29968,   29968,   29968,     1.7,     1.6,     2.9,     3.6,     7.0,     8.2,   21.0,  0.17943,      0,      0,       0,       0,       0,       0
total,       1105490,   28034,   28034,   28034,     1.8,     1.8,     3.5,     4.6,     5.3,    13.8,   22.0,  0.17609,      0,      0,       0,       0,       0,       0
total,       1132221,   26731,   26731,   26731,     1.9,     1.8,     3.8,     5.2,     8.4,    11.1,   23.0,  0.17314,      0,      0,       0,       0,       0,       0
total,       1162149,   29928,   29928,   29928,     1.7,     1.7,     3.0,     4.5,     8.0,     9.1,   24.0,  0.16950,      0,      0,       0,       0,       0,       0
...
```

After:
```
type       total ops,    op/s,    pk/s,   row/s,    mean,     med,     .95,     .99,    .999,     max,   time,   stderr, errors,  gc: #,  max ms,  sum ms,  sdv ms,      mb
...
total,        822863,   94379,   94379,   94379,     0.5,     0.3,     2.0,     2.0,     2.1,     3.7,    9.0,  0.06669,      0,      0,       0,       0,       0,       0
total,        937337,  114474,  114474,  114474,     0.4,     0.2,     2.0,     2.0,     2.1,     3.4,   10.0,  0.06301,      0,      0,       0,       0,       0,       0
total,        986630,   49293,   49293,   49293,     1.0,     1.0,     2.0,     2.1,    17.9,    19.0,   11.0,  0.07318,      0,      0,       0,       0,       0,       0
total,       1026734,   40104,   40104,   40104,     1.2,     1.0,     2.0,     2.2,     6.3,     7.1,   12.0,  0.08410,      0,      0,       0,       0,       0,       0
total,       1066124,   39390,   39390,   39390,     1.3,     1.0,     2.0,     2.2,     2.6,     3.4,   13.0,  0.09108,      0,      0,       0,       0,       0,       0
total,       1103082,   36958,   36958,   36958,     1.3,     1.1,     2.1,     2.5,     3.1,     4.2,   14.0,  0.09643,      0,      0,       0,       0,       0,       0
total,       1141987,   38905,   38905,   38905,     1.3,     1.0,     2.0,     2.4,    11.4,    12.7,   15.0,  0.09894,      0,      0,       0,       0,       0,       0
total,       1180023,   38036,   38036,   38036,     1.3,     1.0,     2.0,     3.7,     5.6,     7.1,   16.0,  0.10070,      0,      0,       0,       0,       0,       0
total,       1216481,   36458,   36458,   36458,     1.4,     1.0,     2.1,     3.6,     4.7,     5.0,   17.0,  0.10210,      0,      0,       0,       0,       0,       0
total,       1256819,   40338,   40338,   40338,     1.2,     1.0,     2.0,     2.2,     3.5,     5.4,   18.0,  0.10173,      0,      0,       0,       0,       0,       0
total,       1295122,   38303,   38303,   38303,     1.3,     1.0,     2.0,     2.4,    21.0,    21.1,   19.0,  0.10136,      0,      0,       0,       0,       0,       0
total,       1334743,   39621,   39621,   39621,     1.3,     1.0,     2.0,     2.3,     3.3,     4.0,   20.0,  0.10055,      0,      0,       0,       0,       0,       0
total,       1375579,   40836,   40836,   40836,     1.2,     1.0,     2.0,     2.1,     3.4,     5.7,   21.0,  0.09927,      0,      0,       0,       0,       0,       0
total,       1415576,   39997,   39997,   39997,     1.2,     1.0,     2.0,     2.3,     3.2,     4.1,   22.0,  0.09807,      0,      0,       0,       0,       0,       0
total,       1449268,   33692,   33692,   33692,     1.5,     1.4,     2.5,     3.2,     4.2,     5.6,   23.0,  0.09800,      0,      0,       0,       0,       0,       0
total,       1471873,   22605,   22605,   22605,     2.2,     2.0,     4.8,     5.9,     7.0,     7.9,   24.0,  0.10015,      0,      0,       0,       0,       0,       0
...
```

Fixes: https://github.com/scylladb/scylladb/issues/24411

This is a new feature, so no backport needed.

Closes scylladb/scylladb#25412

* github.com:scylladb/scylladb:
  docs: workload-prioritization: add driver service level
  test: add test to verify use of `sl:driver`
  transport: use `sl:driver` to handle driver's control connections
  transport: whitespace only change in update_scheduling_group
  transport: call update_scheduling_group for non-auth connections
  generic_server: transport: start using `sl:driver` for new connections
  test: add test_desc_* for driver service level
  test: service_levels: add tests for sl:driver creation and removal
  test: add reload_raft_topology_state() to ScyllaRESTAPIClient
  service_level_controller: automatically create `sl:driver`
  service_level_controller: methods to create driver service level
  service_level_controller: handle special sl:driver in DESC output
  topology_coordinator: add service_level_controller reference
  system_keyspace: add service_level_driver_created
  test: add MAX_USER_SERVICE_LEVELS
2025-09-18 19:45:17 +03:00
Andrzej Jackowski
dd9b4c64d2 system_keyspace: add service_level_driver_created
This commit extends sytem.scylla_local table with an additional
key/value pair that can be used later in this patch series to
keep an information that `sl:driver` was already created. The purpose
of storing this information is to ensure that `sl:driver` is
not recreated after being intentionally removed.

A new mutation is included in `register_raft_pull_snapshot` to keep
`service_level_driver_created` in state machine shapshot, which is
required for proper propagation of the value when a new node is added
to the cluster.

Refs: scylladb/scylladb#24411
2025-09-18 09:28:32 +02:00
Michael Litvak
aa61f074b5 cdc: helper functions for reading metadata from tables
Define functions in system_keyspace that read from the internal cdc
tables and construct the data into internal cdc data structures.
2025-09-17 14:47:12 +02:00
Michael Litvak
b9ee28eaab cdc: add internal tables for cdc with tablets
Add new group0-based tables in system keyspace to be used for cdc with tablets:
* cdc_streams_state - describing "base" state of CDC streams for each
  table - an initial timestamp and a stream set.
* cdc_streams_history - describing following committed stream sets by
  diffs (opened / closed streams) from the previous set.
2025-09-17 14:47:11 +02:00
Ernest Zaslavsky
d624413ddd treewide: Move query related files to a new query directory
As requested in #22120, moved the files and fixed other includes and build system.

Moved files:
- query.cc
- query-request.hh
- query-result.hh
- query-result-reader.hh
- query-result-set.cc
- query-result-set.hh
- query-result-writer.hh
- query_id.hh
- query_result_merger.hh

Fixes: #22120

This is a cleanup, no need to backport

Closes scylladb/scylladb#25105
2025-09-16 23:40:47 +03:00
Sergey Zolotukhin
2640b288c2 raft: disable caching for raft log.
This change disables caching for raft log table due to the following reasons:
* Immediate reason is a deficiency in handling emerging range tombstones in the cache, which causes stalls.
* Long-term reason is that sequential reads from the raft log do not benefit from the cache, making it better to bypass it to free up space and avoid stalls.

Fixes scylladb/scylladb#26027

Closes scylladb/scylladb#26031
2025-09-16 23:40:47 +03:00
Calle Wilund
bc20861afb system_keyspace: Prune dropped tables from truncation on start/drop
Fixes #25683

Once a table drop is complete, there should be no reason to retain
truncation records for it, as any replay should skip mutations
anyway (no CF), and iff we somehow resurrect a dropped table,
this replay-resurrected data is the least problem anyway.

Adds a prune phase to the startup drop_truncation_rp_records run,
which ignores updating, and instead deletes records for non-existant
tables (which should patch any existing servers with lingering data
as well).

Also does an explicit delete of records on actual table DROP, to
ensure we don't grow this table more than needed even in long
uptime nodes.

Small unit test included.

Closes scylladb/scylladb#25699
2025-09-03 07:25:34 +03:00
Avi Kivity
1f4c9b1528 Merge 'system_keyspace: add peers cache to get_ip_from_peers_table' from Petr Gusev
The gossiper can call `storage_service::on_change` frequently (see  scylladb/scylla-enterprise#5613), which may cause high CPU load and even trigger OOMs or related issues.

This PR adds a temporary cache for `system.peers` to resolve host_id -> ip without hitting storage on every call. The cache is short-lived to handle the unlikely case where `system.peers` is updated directly via CQL.

This is a temporary fix; a more thorough solution is tracked in https://github.com/scylladb/scylladb/issues/25620.

Fixes scylladb/scylladb#25660

backport: this patch needs to be backported to all supported versions (2025.1/2/3).

Closes scylladb/scylladb#25658

* github.com:scylladb/scylladb:
  storage_service: move get_host_id_to_ip_map to system_keyspace
  system_keyspace: use peers cache in get_ip_from_peers_table
  storage_service: move get_ip_from_peers_table to system_keyspace
2025-08-31 15:34:35 +03:00
Piotr Dulikowski
7ccb50514d Merge 'Introduce view building coordinator' from Michał Jadwiszczak
This patch introduces `view_building_coordinator`, a single entity within whole cluster responsible for building tablet-based views.

The view building coordinator takes slightly different approach than the existing node-local view builder. The whole process is split into smaller view building tasks, one per each tablet replica of the base table.
The coordinator builds one base table at a time and it can choose another when all views of currently processing base table are built.
The tasks are started by setting `STARTED` state and they are executed by node-local view building worker. The tasks are scheduled in a way, that each shard processes only one tablet at a time (multiple tasks can be started for a shard on a node because a table can have multiple views but then all tasks have the same base table and tablet (last_token)). Once the coordinator starts the tasks, it sends `work_on_view_building_tasks` RPC to start the tasks and receive their results.
This RPC is resilient to RPC failure or raft leader change, meaning if one RPC call started a batch of tasks but then failed (for instance the raft leader was changed and caller aborted waiting for the response), next RPC call will attach itself to the already started batch.

The coordinator plugs into handling tablet operations (migration/resize/RF change) and adjusts its tasks accordingly. At the start of each tablet operation, the coordinator aborts necessary view building tasks to prevent https://github.com/scylladb/scylladb/issues/21564. Then, new adjusted tasks are created at the end of the operation.
If the operation fails at any moment, aborted tasks are rollback.

The view building coordinator can also handle staging sstables using process_staging view building tasks. We do this because we don't want to start generating view updates from a staging sstable prematurely, before the writes are directed to the new replica (https://github.com/scylladb/scylladb/issues/19149).

For detailed description check: `docs/dev/view-building-coordinator.md`

Fixes https://github.com/scylladb/scylladb/issues/22288
Fixes https://github.com/scylladb/scylladb/issues/19149
Fixes https://github.com/scylladb/scylladb/issues/21564
Fixes https://github.com/scylladb/scylladb/issues/17603
Fixes https://github.com/scylladb/scylladb/issues/22586
Fixes https://github.com/scylladb/scylladb/issues/18826
Fixes https://github.com/scylladb/scylladb/issues/23930

---

This PR is reimplementation of https://github.com/scylladb/scylladb/pull/21942

Closes scylladb/scylladb#23760

* github.com:scylladb/scylladb:
  test/cluster: add view build status tests
  test/cluster: add view building coordinator tests
  utils/error_injection: allow to abort `injection_handler::wait_for_message()`
  test: adjust existing tests
  utils/error_injection: add injection with `sleep_abortable()`
  db/view/view_builder: ignore `no_such_keyspace` exception
  docs/dev: add view building coordinator documentation
  db/view/view_building_worker: work on `process_staging` tasks
  db/view/view_building_worker: register staging sstable to view building coordinator when needed
  db/view/view_building_worker: discover staging sstables
  db/view/view_building_worker: add method to register staging sstable
  db/view/view_update_generator: add method to process staging sstables instantly
  db/view/view_update_generator: extract generating updates from staging sstables to a method
  db/view/view_update_generator: ignore tablet-based sstables
  db/view/view_building_coordinator: update view build status on node join/left
  db/view/view_building_coordinator: handle tablet operations
  db/view: add view building task mutation builder
  service/topology_coordinator: run view building coordinator
  db/view: introduce `view_building_coordinator`
  db/view/view_building_worker: update built views locally
  db/view: introduce `view_building_worker`
  db/view: extract common view building functionalities
  db/view: prepare to create abstract `view_consumer`
  message/messaging_service: add `work_on_view_building_tasks` RPC
  service/topology_coordinator: make `term_changed_error` public
  db/schema_tables: create/cleanup tasks when an index is created/dropped
  service/migration_manager: cleanup view building state on drop keyspace
  service/migration_manager: cleanup view building state on drop view
  service/migration_manager: create view building tasks on create view
  test/boost: enable proxy remote in some tests
  service/migration_manager: pass `storage_proxy` to `prepare_keyspace_drop_announcement()`
  service/migration_manager: coroutinize `prepare_new_view_announcement()`
  service/storage_proxy: expose references to `system_keyspace` and `view_building_state_machine`
  service: reload `view_building_state_machine` on group0 apply()
  service/vb_coordinator: add currently processing base
  db/system_keyspace: move `get_scylla_local_mutation()` up
  db/system_keyspace: add `view_building_tasks` table
  db/view: add view_building_state and views_state
  db/system_keyspace: add method to get view build status map
  db/view: extract `system.view_build_status_v2` cql statements to system_keyspace
  db/system_keyspace: move `internal_system_query_state()` function earlier
  db/view: ignore tablet-based views in `view_builder`
  gms/feature_service: add VIEW_BUILDING_COORDINATOR feature
2025-08-29 17:28:44 +02:00
Petr Gusev
4b907c7711 storage_service: move get_host_id_to_ip_map to system_keyspace
Reimplemented the function to use the peers cache. It could be replaced
with get_ip_from_peers_table, but that would create a coroutine frame for
each call.
2025-08-28 12:48:46 +02:00
Petr Gusev
de5dc4c362 system_keyspace: use peers cache in get_ip_from_peers_table
The storage_service::on_change method can be called quite often
by the gossiper, see scylladb/scylla-enterprise#5613. In this commit
we introduce a temporal cache for system.peers so that we don't have
to go to the storage each time we need to resolve host_id -> ip.
We keep the cache only for a small amount of time to handle the
(unlikely) scenario when the user wants to update system.peers table
from CQL.

Fixes scylladb/scylladb#25660
2025-08-28 12:48:39 +02:00
Petr Gusev
91c633371e storage_service: move get_ip_from_peers_table to system_keyspace
We plan to add a cache to get_ip_from_peers_table in upcoming commits.
It's more convenient to do this from system_keyspace, since the only two
methods that mutate system.peers (remove_endpoint and update_peers_info)
are already there.
2025-08-28 12:30:41 +02:00
Calle Wilund
2eccd17e70 system_keyspace: Limit parallelism in drop_truncation_records
Fixes #25682
Refs scylla-enterprise#5580

If the truncation table is large in entries, we might create a
huge parallel execution, quite possibly consuming loads of resources
doing something quite trivial.
Limit concurrency to a small-ish number

Closes scylladb/scylladb#25678
2025-08-28 12:50:00 +03:00
Michał Jadwiszczak
d5d81591db service/vb_coordinator: add currently processing base
The view building coordinator will be building all views
of one base table at a time.
Select first available base table as currently processing base
and save this information to `system.scylla_local`.
2025-08-27 08:55:47 +02:00
Michał Jadwiszczak
e0184377ca db/system_keyspace: move get_scylla_local_mutation() up
So it can be used by all helper functions, keeping the logical order from
the header file.
2025-08-27 08:55:47 +02:00
Michał Jadwiszczak
46a24d960d db/system_keyspace: add view_building_tasks table
The table is managed by group0 and uses schema commitlog.
The commit also includes helper functions.
2025-08-27 08:55:47 +02:00
Michał Jadwiszczak
ce1890e512 db/system_keyspace: add method to get view build status map 2025-08-27 08:55:47 +02:00
Michał Jadwiszczak
f90dd522df db/view: extract system.view_build_status_v2 cql statements to system_keyspace
Until now, all changes to `system.view_build_status_v2` were made from
view.cc and the file contained all of the helper methods.

This commit introduces a `build_status` enum class to avoid using
hardcoded strings and extracts the helper methods to `system_keyspace`
class, so they can be later used by the view building coordinator.
2025-08-27 08:55:46 +02:00
Michał Jadwiszczak
18609adfce db/system_keyspace: move internal_system_query_state() function earlier
So it can be used in all system keyspace proxy methods while maintaining
the same order as in the header file.
2025-08-27 08:55:46 +02:00
Piotr Dulikowski
ec7832cc84 Merge 'Raft-based recovery procedure: simplify rolling restart with recovery_leader' from Patryk Jędrzejczak
The following steps are performed in sequence as part of the
Raft-based recovery procedure:
- set `recovery_leader` to the host ID of the recovery leader in
  `scylla.yaml` on all live nodes,
- send the `SIGHUP` signal to all Scylla processes to reload the config,
- perform a rolling restart (with the recovery leader being restarted
  first).

These steps are not intuitive and more complicated than they could be.

In this PR, we simplify these steps. From now on, we will be able to
simply set `recovery_leader` on each node just before restarting it.

Apart from making necessary changes in the code, we also update all
tests of the Raft-based recovery procedure and the user-facing
documentation.

Fixes scylladb/scylladb#25015

The Raft-based procedure was added in 2025.2. This PR makes the
procedure simpler and less error-prone, so it should be backported
to 2025.2 and 2025.3.

Closes scylladb/scylladb#25032

* github.com:scylladb/scylladb:
  docs: document the option to set recovery_leader later
  test: delay setting recovery_leader in the recovery procedure tests
  gossip: add recovery_leader to gossip_digest_syn
  db: system_keyspace: peers_table_read_fixup: remove rows with null host_id
  db/config, gms/gossiper: change recovery_leader to UUID
  db/config, utils: allow using UUID as a config option
2025-08-04 08:29:32 +02:00
Petr Gusev
8292ecf2e1 paxos_state: inline system_keyspace functions into paxos_store
Prepares for reusing the same functions to access either
system.paxos or a co-located table.
2025-07-24 16:39:50 +02:00
Patryk Jędrzejczak
23f59483b6 db: system_keyspace: peers_table_read_fixup: remove rows with null host_id
Currently, `peers_table_read_fixup` removes rows with no `host_id`, but
not with null `host_id`. Null host IDs are known to appear in system
tables, for example in `system.cluster_status` after a failed bootstrap.
We better make sure we handle them properly if they ever appear in
`system.peers`.

This commit guarantees that null UUID cannot belong to
`loaded_endpoints` in `storage_service::join_cluster`, which in
particular ensures that we throw a runtime error when a user sets
`recovery_leader` to null UUID during the recovery procedure. This is
handled by the code verifying that `recovery_leader` belongs to
`loaded_endpoints`.
2025-07-23 15:36:56 +02:00
Botond Dénes
0753643606 db/system_keyspace: add apply_mutation()
Allow applying writes in the form of mutations directly to the keyspace.
Allows lower-level mutation API to build writes. Advantageous if writes
can contain large cells that would otherwise possibly cause large
allocation warnings if used via the internal CQL API.
2025-06-24 11:05:30 +03:00
Botond Dénes
92b5fe8983 db/system_keyspace: introduce the corrupt_data table
To serve as a place to store corrupt mutation fragments. These fragments
cannot be written to sstables, as they would be spread around by
compaction and/or repair. They even might make parsing the sstable
impossible. So they are stored in this special table instead, kept
around to be inspected later and possibly restored if possible.
2025-06-24 11:05:30 +03:00
Gleb Natapov
a0a3a034e0 topology coordinator: Implement global topology request queue
Requests, together with their parameters, are added to the
topology_request tables and the queue of active global requests is
kept in topology state. Thy are processed one by one by the topology
state machine.

Fixes: #16822
2025-06-11 11:29:33 +03:00