Commit Graph

51320 Commits

Author SHA1 Message Date
Andrei Chekun
e074e21490 test.py: introduce new environment variable TESTPY_PREPARED_ENVIRONMENT
Introduce the new environment variable that will be used to signalize to the pytest runner that environment war already prepared by test.py. This needed to be able to run the test with pytest and test.py(that actually will run pytest underneath).
2026-01-09 11:59:25 +01:00
Patryk Jędrzejczak
eee2b6c7af Merge 'tablets: Make balancing disabling RPC preempt tablet transitions' from Tomasz Grabiec
Disabling of balancing waits for topology state machine to become idle, to guarantee that no migrations are happening or will happen after the call returns. But it doesn't interrupt the scheduler, which means the call can take arbitrary amount of time. It may wait for tablet repair to be finished, which can take many hours.

We should do it via topology request, which will interrupt the tablet scheduler.

Enabling of balancing can be immediate.

Fixes https://github.com/scylladb/scylladb/issues/27647
Fixes #27210

Closes scylladb/scylladb#27736

* https://github.com/scylladb/scylladb:
  test: Verify that repair doesn't block disabling of tablet load balancing
  tablets: Make balancing disabling call preempt tablet transitions
2026-01-08 21:55:19 +02:00
Piotr Dulikowski
8e3e39a64a Merge 'service/storage_service: update service levels cache after upgrade to v2' from Michał Jadwiszczak
Service levels cache is empty after upgrade to consistent topology
if no mutations are commited to `system.service_levels_v2` or rolling
restart is not done.

To fix the bug, this patch adds service levels cache reloading after
upgrading the SL data accessor to v2 in `storage_service::topology_state_load()`.

Fixes [SCYLLADB-90](https://scylladb.atlassian.net/browse/SCYLLADB-90)

This fix should be backported to all versions containing service levels on Raft.

[SCYLLADB-90]: https://scylladb.atlassian.net/browse/SCYLLADB-90?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Closes scylladb/scylladb#27585

* github.com:scylladb/scylladb:
  service/storage_service: update service levels cache after upgrade to v2
  service/storage_service: check if service levels were already upgraded before doing migration to raft
2026-01-08 21:55:19 +02:00
Michał Hudobski
e2e479f20d auth: fix cdc vector search indexing permission bug
VECTOR_SEARCH_INDEXING permission didn't work on cdc tables as we mistakenly checked for vector indexes on the cdc table insted of the base.
This patch fixes that and adds a test that validates this behavior.

Fixes: VECTOR-476

Closes scylladb/scylladb#28050
2026-01-08 21:55:19 +02:00
Ernest Zaslavsky
19fe630c0e Update seastar submodule
seastar 4dcd4df..dd46b6fe
```
dd46b6fe net: expose DNS TTL via net::hostent
b94f81b0 test: Extend statat() test to check ENOENT exception reporting
```

Closes scylladb/scylladb#28006
2026-01-08 21:55:19 +02:00
Michael Litvak
8f15c7a874 db/view/view_update_generator: move discover_staging_sstables to start
Call discover_staging_sstables in view_update_generator::start() instead
of in the constructor, because the constructor is called during
initialization before sstables are loaded.

The initialization order was changed in 5d1f74b86a and caused this
regression. It means the view update generator won't discover staging
sstables on startup and view updates won't be generated for them. It
also causes issues in sstable cleanup.

view_update_generator::start() is called in a later stage of the
initialization, after sstable loading, so do the discovery of staging
sstables there.

Fixes scylladb/scylladb#27956

Closes scylladb/scylladb#27970
2026-01-08 21:55:19 +02:00
Botond Dénes
8c72dcc1ec Merge 'database: truncate_table_on_all_shards: consider can_flush on all shards' from Benny Halevy
Currently, database::truncate_table_on_all_shards calls the table::can_flush only on the coordinator shard
and therefore it may miss shards with dirty data if the coordinator shard happens to have empty memtables, leading to clearing the memtables with dirty data rather than flushing them.

This change fixes that by making flush safe to be called, even if the memtable list is empty, and calling it on every shard that can flush (i.e. seal_immediate_fn is engaged).

Also, change database_test::do_with_some_data is use random keys instead of hard-coded key names, to reproduce this issue with `snapshot_list_contains_dropped_tables`.

Fixes #27639

* The issue exists since forever and might cause data loss due to wrongly clearing the memtable, so it needs backport to all live versions

Closes scylladb/scylladb#27643

* github.com:scylladb/scylladb:
  test: database_test: do_with_some_data: randomize keys
  database: truncate_table_on_all_shards: drop outdated TODO comment
  database: truncate_table_on_all_shards: consider can_flush on all shards
  memtable_list: unify can_flush and may_flush
  test: database_test: add test_flush_empty_table_waits_on_outstanding_flush
  replica: table, storage_group, compaction_group: add needs_flush
  test: database_test: do_with_some_data_in_thread: accept void callback function
2026-01-08 21:55:19 +02:00
Avi Kivity
633e6e0037 build: update toolchain generation procedure for optimized clang
Explain where to pick up existing clang archives, and how to upload new ones.

Closes scylladb/scylladb#27690
2026-01-08 21:55:18 +02:00
Evgeniy Naydanov
a9da14be19 test: dtest: reproducer for parallel rebuild failure
2-DC cluster parallel non-RBNO rebuild failure when expanding RF in DC2.

Steps to reproduce:
    1. Provision a cluster with 2 datacenters and at least 2 nodes in the second datacenter.
    2. Let’s assume datacenter names are "dc1" and "dc2".
    3. Create a keyspace ("keyspace1") with RF=0 in dc2.
    4. Populate some data into dc1.
    5. Change keyspace1 replication in dc2 to 2.
    6. On 2 nodes in dc2 run the following command in parallel:
         nodetool rebuild --source-dc dc1

Parallel execution of rebuilds is not possible with RBNO enabled.

This test is the repro for #27804

Closes scylladb/scylladb#27747
2026-01-08 21:55:18 +02:00
Botond Dénes
9b4a7f1d14 Merge 'test: cluster: object_store: test_backup: modernize do_abort_restore' from Benny Halevy
Currently the function uses a regular expression
to check the system log for a specific message.
This is tangential to the ability to cleanly abort the restore task, plus the regular expression has a syntax error:
```
test/cluster/object_store/test_backup.py:534
  /home/bhalevy/dev/scylla/test/cluster/object_store/test_backup.py:534: SyntaxWarning: "\(" is an invalid escape sequence. Such sequences will not work in the future. Did you mean "\\("? A raw string is also an option.
    await wait_for_first_completed([l.wait_for("Failed to handle STREAM_MUTATION_FRAGMENTS \(receive and distribute phase\) for .+: Streaming aborted", timeout=10) for l in logs])
```

Thsi change modernizes the implementation by:
- using auto_dc_rack for manager.servers_add
- using new_test_keyspace to generate and auto delete the keyspace
- using async gatherio and a prepared statement to insert the data
- simplifing the keys and values by NOT using os.urandom (that is notoriously slow)
- inserting fewer keys in debug mode
- removing the log check

With that, the test can be reenabled in all modes.

* No backport needed since the test was disabled

Closes scylladb/scylladb#27892

* github.com:scylladb/scylladb:
  test_backup: do_abort_restore: reduce data footprint
  test_backup: do_abort_restore: use error injection
  test_backup: do_abort_restore: use asyncio for cql
  test_backup: do_abort_restore: use new_test_keyspace
  test_backup: do_abort_restore: use logger rather than print
  test_backup: do_abort_restore: pass auto_rack_dc to servers_add
2026-01-08 21:55:18 +02:00
Anna Stuchlik
f614482e66 doc: add the patch release upgrade procedure for version 2025.4
Adds the patch upgrade guide based on previous upgrade guides.

Fixes https://github.com/scylladb/scylladb/issues/27982

Closes scylladb/scylladb#27985
2026-01-08 21:55:18 +02:00
Asias He
4f77dd058d 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#27679
2026-01-08 21:55:18 +02:00
Anna Stuchlik
3f1c7c70f5 doc: remove the link to the Download Center
... from the OS support page.

Fixes https://github.com/scylladb/scylladb/issues/28047

Closes scylladb/scylladb#28048
2026-01-08 21:55:18 +02:00
Asias He
0aabf51380 repair: Fix sstable_list_to_mark_as_repaired with multishard writer
It was obseved:

```
test_repair_disjoint_row_2nodes_diff_shard_count was spuriously failing due to
segfault.

backtrace pointed to a failure when allocating an object from the chain of
freed objects, which indicates memory corruption.

(gdb) bt
    at ./seastar/include/seastar/core/shared_ptr.hh:275
    at ./seastar/include/seastar/core/shared_ptr.hh:430
Usual suspect is use-after-free, so ran the reproducer in the sanitize mode,
which indicated shared ptr was being copied into another cpu through the
multi shard writer:

seastar - shared_ptr accessed on non-owner cpu, at: ...
--------
seastar::smp_message_queue::async_work_item<mutation_writer::multishard_writer::make_shard_writer...

```

The multishard writer itself was fine, the problem was in the streaming consumer
for repair copying a shared ptr. It could work fine with same smp setting, since
there will be only 1 shard in the consumer path, from rpc handler all the way
to the consumer. But with mixed smp setting, the ptr would be copied into the
cpus involved, and since the shared ptr is not cpu safe, the refcount change
can go wrong, causing double free, use-after-free.

To fix, we pass a generic incremental repair handler to the streaming
consumer. The handler is safe to be copied to different shards. It will
be a no op if incremental repair is not enabled or on a different shard.

A reproducer test is added. The test could reproduce the crash
consistently before the fix and work well after the fix.

Fixes #27666

Closes scylladb/scylladb#27870
2026-01-08 21:55:18 +02:00
Radosław Cybulski
5f48ab3875 storage_proxy: fix invalid assert
Change invalid `assert(true)` into `SCYLLA_ASSERT(false)`, as
the latter was clearly meant.

Closes scylladb/scylladb#27900
2026-01-08 21:55:18 +02:00
Andrei Chekun
c950c2e582 test.py: convert skip_mode function to pytest.mark
Function skip_mode works only on function and only in cluster test. This if OK
when we need to skip one test, but it's not possible to use it with pytestmark
to automatically mark all tests in the file. The goal of this PR is to migrate

skip_mode to be dynamic pytest.mark that can be used as ordinary mark.

Closes scylladb/scylladb#27853

[avi: apply to test/cluster/test_tablets.py::test_table_creation_wakes_up_balancer]
2026-01-08 21:55:16 +02:00
Tomasz Grabiec
a52de4ecdc test: cluster: test_topology_ops[_encrypted]: Fix failures due to background migrations fencing out writes
The test if flaky, with failures in:

        for server in servers:
>           await check_node_log_for_failed_mutations(manager, server)

test/cluster/test_topology_ops_encrypted.py:84:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

manager = <test.pylib.manager_client.ManagerClient object at 0xffff602e8590>
server = ServerInfo(server_id=1769, ip_addr='127.82.127.43', rpc_address='127.82.127.43', datacenter='DEFAULT_DC', rack='DEFAULT_RACK', pid=186578)

    async def check_node_log_for_failed_mutations(manager: ManagerClient, server: ServerInfo):
        logging.info(f"Checking that node {server} had no failed mutations")
        log = await manager.server_open_log(server.server_id)
        occurrences = await log.grep(expr="Failed to apply mutation from", filter_expr="(TRACE|DEBUG|INFO)")
>       assert len(occurrences) == 0
E       AssertionError

test/cluster/util.py:319: AssertionError

As diagnosed by Gleb in https://github.com/scylladb/scylladb/issues/27942#issuecomment-3710013625:

"The fencing errors here look legit given that we do not wait for all
requests to complete while shutting down the storage proxy. The
scenario is this:

Test does writes to rf=3 keyspace with cl=one. One node is shutting
down while there is a tablet migration. Tablet migration executes
barrier and drain which fails on a node that is been shutdown. The
topology coordinator proceeds fencing the old topology, but there
still can be un-handled mutation requests from the shutting down node
on other nodes and they will generate fencing errors like they should.

They way to avoid it (though it is benign) is to wait for all outgoing
storage proxy requests to complete during shutdown, but even then the
error may still happen since a request may timeout before it is
processed by the other side, so it may be completed by a storage proxy
coordinator side, but still not handled by replica side. This what we
have fencing for in the first place."

Fix by diabling background tablet migrations, so that we have no
topology barriers concurrent with node shutdown.

Fixes #27942

Closes scylladb/scylladb#28034
2026-01-08 21:53:47 +02:00
Tomasz Grabiec
34df158605 test: cluster: Fix NoHostAvailable error in test_not_enough_token_owners
The driver must see server_c before we stop server_a, otherwise
there will be no live host in the pool when we attempt to drop
the keyspace:

```
   @pytest.mark.asyncio
    async def test_not_enough_token_owners(manager: ManagerClient):
        """
        Test that:
        - the first node in the cluster cannot be a zero-token node
        - removenode and decommission of the only token owner fail in the presence of zero-token nodes
        - removenode and decommission of a token owner fail in the presence of zero-token nodes if the number of token
          owners would fall below the RF of some keyspace using tablets
        """
        logging.info('Trying to add a zero-token server as the first server in the cluster')
        await manager.server_add(config={'join_ring': False},
                                 property_file={"dc": "dc1", "rack": "rz"},
                                 expected_error='Cannot start the first node in the cluster as zero-token')

        logging.info('Adding the first server')
        server_a = await manager.server_add(property_file={"dc": "dc1", "rack": "r1"})

        logging.info('Adding two zero-token servers')
        # The second server is needed only to preserve the Raft majority.
        server_b = (await manager.servers_add(2, config={'join_ring': False}, property_file={"dc": "dc1", "rack": "rz"}))[0]

        logging.info(f'Trying to decommission the only token owner {server_a}')
        await manager.decommission_node(server_a.server_id,
                                        expected_error='Cannot decommission the last token-owning node in the cluster')

        logging.info(f'Stopping {server_a}')
        await manager.server_stop_gracefully(server_a.server_id)

        logging.info(f'Trying to remove the only token owner {server_a} by {server_b}')
        await manager.remove_node(server_b.server_id, server_a.server_id,
                                  expected_error='cannot be removed because it is the last token-owning node in the cluster')

        logging.info(f'Starting {server_a}')
        await manager.server_start(server_a.server_id)

        logging.info('Adding a normal server')
        await manager.server_add(property_file={"dc": "dc1", "rack": "r2"})

        cql = manager.get_cql()

        await wait_for_cql_and_get_hosts(cql, [server_a], time.time() + 60)

>       async with new_test_keyspace(manager, "WITH replication = {'class': 'NetworkTopologyStrategy', 'replication_factor': 2} AND tablets = { 'enabled': true }") as ks_name:

test/cluster/test_not_enough_token_owners.py:57:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/usr/lib64/python3.14/contextlib.py:221: in __aexit__
    await anext(self.gen)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

manager = <test.pylib.manager_client.ManagerClient object at 0x7f37efe00830>
opts = "WITH replication = {'class': 'NetworkTopologyStrategy', 'replication_factor': 2} AND tablets = { 'enabled': true }"
host = None

    @asynccontextmanager
    async def new_test_keyspace(manager: ManagerClient, opts, host=None):
        """
        A utility function for creating a new temporary keyspace with given
        options. It can be used in a "async with", as:
            async with new_test_keyspace(ManagerClient, '...') as keyspace:
        """
        keyspace = await create_new_test_keyspace(manager.get_cql(), opts, host)
        try:
            yield keyspace
        except:
            logger.info(f"Error happened while using keyspace '{keyspace}', the keyspace is left in place for investigation")
            raise
        else:
>           await manager.get_cql().run_async("DROP KEYSPACE " + keyspace, host=host)
E           cassandra.cluster.NoHostAvailable: ('Unable to complete the operation against any hosts', {<Host: 127.69.108.39:9042 dc1>: ConnectionException('Pool for 127.69.108.39:9042 is shutdown')})

test/cluster/util.py:544: NoHostAvailable
```

Fixes #28011

Closes scylladb/scylladb#28040
2026-01-08 21:53:47 +02:00
Andrei Chekun
ee0bf35615 test.py: add custome exit code for pytest in case maxfail reached
This PR adds custom exit code in case when maxfail reached. This is
needed for easier detection why pytest failed in CI.

Closes scylladb/scylladb#28018
2026-01-08 21:53:47 +02:00
Benny Halevy
ebd667a8e0 test: database_test: do_with_some_data: randomize keys
With randomized keys, and since we're inserting only 2 keys,
it is possible that they would end up owned only by a single shard,
reproducing #27639 in snapshot_list_contains_dropped_tables.

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:49:46 +02:00
Benny Halevy
93b827c185 database: truncate_table_on_all_shards: drop outdated TODO comment
The comment was added in 83323e155e
Since then, table::seal_active_memtable was improved to guarantee
waiting on oustanding flushes on success (See d55a2ac762), so
we can remove this TODO comment (it also not covered by any issue
so nobody is planned to ever work on it).

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:49:46 +02:00
Benny Halevy
2a803d2261 database: truncate_table_on_all_shards: consider can_flush on all shards
can_flush might return a different value for each shard
so check it right before deciding whether to flush or clear a memtable
shard.

Note that under normal condition can_flush would always return true
now that it checks only the presence of the seal memtable function
rather than check memtable_list::empty().

Fixes #27639

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:49:46 +02:00
Benny Halevy
02ee341a03 memtable_list: unify can_flush and may_flush
Now that we have a unit test proving that it's safe to flush an
empty memtable list there is no need to distinguish between
may_flush and can_flush.

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:49:46 +02:00
Benny Halevy
0342a24ee0 test: database_test: add test_flush_empty_table_waits_on_outstanding_flush
Test that table::flush waits on outstanding flushes, even if the active memtable is empty

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:49:45 +02:00
Benny Halevy
5be6b80936 replica: table, storage_group, compaction_group: add needs_flush
Table needs flush if not all its memtable lists are empty.
To be used in the next patch for a unit test.

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:41:22 +02:00
Benny Halevy
ec4069246d test: database_test: do_with_some_data_in_thread: accept void callback function
Many test cases already assume `func` is being called a seastar
thread and although the function they pass returns a (ready) future,
it serves no purpose other than to conform to the interface.

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-08 09:41:22 +02:00
Patryk Jędrzejczak
946a2bb988 storage_service: do not call raft_topology_update_ip for left nodes
This `raft_topology_update_ip` call always returns after `t.find(raft_id)`
returns `nullptr`, so it effectively does nothing. It's not a bug, since
there is no reason to update `system.peers` for left nodes anyway. We
delete the rows corresponding to left nodes in `process_left_node` (called
just above).

Closes scylladb/scylladb#27899
2026-01-07 16:52:13 +01:00
Michał Jadwiszczak
be16e42cb0 service/storage_service: update service levels cache after upgrade to v2
Service levels cache is empty after upgrade to consistent topology
if no mutations are commited to `system.service_levels_v2` or rolling
restart is not done.

To fix the bug, this commit adds service levels cache reloading after
upgrading the SL data accessor to v2 in `storage_service::topology_state_load()`.

Fixes SCYLLADB-90
2026-01-07 14:06:13 +01:00
Michał Jadwiszczak
53d0a2b5dc service/storage_service: check if service levels were already upgraded
before doing migration to raft

There is no need to call `service_level_controller::upgrade_to_v2()`
on every topology state load, we only need to do it once.
2026-01-07 14:06:13 +01:00
Patryk Jędrzejczak
f0d159abb0 Merge 'test/raft: use valid sentinel in liveness check to prevent digest errors' from Emil Maskovsky
Replace -1 with 0 for the liveness check operation to avoid triggering digest validation failures. This prevents rare fatal errors when the cluster is recovering and ensures the test does not violate append_seq invariants.

The value -1 was causing invalid digest results in the append_seq structure, leading to assertion failures. This could happen when the sentinel value was the first (or only) element being appended, resulting in a digest that did not match the expected value.

By using 0 instead, we ensure that the digest calculations remain valid and consistent with the expected behavior of the test.

The specific value of the sentinel is not important, as long as it is a valid elem_t that does not violate the invariants of the append_seq structure. In particular, the sentinel value is typically used only when no valid result is received from any server in the current loop iteration, in which case the loop will retry.

Fixes: scylladb/scylladb#27307

Backporting to active branches - this is a test-only fix (low risk) for a flaky test that exists in older branches (thus affects the CI of active branches).

Closes scylladb/scylladb#28010

* https://github.com/scylladb/scylladb:
  test/raft: use valid sentinel in liveness check to prevent digest errors
  test/raft: improve debugging in randomized_nemesis_test
2026-01-07 12:31:21 +01:00
Łukasz Paszkowski
62313a6264 load_sketch: Allow populating load_sketch with normalized current load
Currently, tablet allocation intentionally ignores current load (
introduced by the commit #1e407ab) which could cause identical shard
selection when allocating a small number of tablets in the same topology.
When a tablet allocator is asked to allocate N tablets (where N is smaller
than the number of shards on a node), it selects the first N lowest shards.
If multiple such tables are created, each allocator run picks the same
shards, leading to tablet imbalance across shards.

This change initializes the load sketch with the current shard load,
scaled into the [0,1] range, ensuring allocation still remains even
while starting from globally least-loaded shards.

Fixes https://github.com/scylladb/scylladb/issues/27620

Closes scylladb/scylladb#27802
2026-01-07 11:49:01 +01:00
Avi Kivity
2642636ada build: avoid ccache masquarading when choosing ccache too
In 12dcf79c60, we avoid the ccache masquarate directory
when choosing sccache, as that would give us a double-caching
effect: first sccache is called, then clang++ is looked up
finding ccache masquarading as clang++. We solved that by
converting the name clang++ to the absolute path /usr/bin/clang++
(or whatever), skipping over the masquarade directory in $PATH.

It turns out that we need to do the same for ccache. That commit
changed the compile command to 'ccache clang++', and ccache will
look up clang++ in $PATH, finding itself in the masquarade directory.

Fix that by avoiding the masquarade directory if a compiler cache is
specified explicitly or is found with --compiler-cache=auto.

Closes scylladb/scylladb#27996
2026-01-06 17:47:09 +02:00
Nadav Har'El
5f79d93102 Merge 'Alternator response compression' from Szymon Malewski
This pull request introduces HTTP response compression to Alternator, allowing responses (both string and chunked) to be compressed using `gzip` or `deflate` when requested by clients and when the response size exceeds configurable thresholds.

* Added new source files `http_compression.cc` and `http_compression.hh` implementing compression logic, including parsing client `Accept-Encoding` headers, selecting compression algorithms, and compressing response bodies using zlib.

* Added two new configuration options to `db::config` (`alternator_response_gzip_compression_level` and `alternator_response_gzip_compression_threshold_in_bytes`) to control compression level (and optionally disable compression with level 0 - no compression) and minimum response size for compression.

* Added tests showing compliance with DynamoDB behavior.

Fixes #27246

New feature - no backporting

Closes scylladb/scylladb#27454

* github.com:scylladb/scylladb:
  alternator/http_compression: Add compression of streamed response
  alternator/http_compression: Add implementation od gzip/deflate of string response
  alternator/http_compression: Add handling of Accept-Encoding header
  test/alternator: add tests for compressed responses
2026-01-06 16:47:11 +02:00
Emil Maskovsky
4ba3e90f33 test/raft: use valid sentinel in liveness check to prevent digest errors
Replace -1 with 0 for the liveness check operation to avoid triggering
digest validation failures. This prevents rare fatal errors when the
cluster is recovering and ensures the test does not violate append_seq
invariants.

The value -1 was causing invalid digest results in the append_seq
structure, leading to assertion failures. This could happen when the
sentinel value was the first (or only) element being appended, resulting
in a digest that did not match the expected value.

By using 0 instead, we ensure that the digest calculations remain valid
and consistent with the expected behavior of the test.

The specific value of the sentinel is not important, as long as it is
a valid elem_t that does not violate the invariants of the append_seq
structure. In particular, the sentinel value is typically used only
when no valid result is received from any server in the current loop
iteration, in which case the loop will retry.

Fixes: scylladb/scylladb#27307
2026-01-06 14:34:02 +01:00
Emil Maskovsky
3af5183633 test/raft: improve debugging in randomized_nemesis_test
Move the post-condition check before the assertion to ensure it is
always executed first. Before, the wrong value could be passed to the
digest_remove assertion, making the pre-check trigger there instead of
the post-check as expected.

Also, add a check in the append_seq constructor to ensure that the
digest value is valid when creating an append_seq object.
2026-01-06 14:32:46 +01:00
Ferenc Szili
a51cb3dad9 test: fix flaky test_update_load_stats_after_migration
Disable load balancing to avoid the balancer moving the tablet from a
node with less to a node with more available disk space. Otherwise, the
move_tablet API can fail (if the tablet is already in transisiton) or
be a no-op (in case the tablet has already been migrated)

Fixes: #27980

Closes scylladb/scylladb#27993
2026-01-06 11:57:35 +02:00
Andrei Chekun
b546315edf test.py: fix race condition in initizlization of cqlpy tests
Fix the race condition when the process finished, while test is trying
to checks its descriptors. Now instead of failing the whole loop, it
will continue to iterate the rest of the process to find the needed
process.

Closes scylladb/scylladb#27994
2026-01-06 10:40:25 +02:00
Avi Kivity
4c9c3aae23 tools: toolchain: add dockerfile for future toolchain
To avoid surprises when libstdc++, clang, or other components
in the toolchain introduce regressions, we introduce a "future
toolchain". This builds on the Fedora version under active
development, and the development branches of gcc and llvm.

The future toolchain is not intended to be frozen. Rather,
periodically we will build the future toolchain, then build
ScyllaDB and run its unit tests under that toolchain, then
discard it. Any problems will then have be be tracked down
by a developer and either reported to the source repository,
or fixed in ScyllaDB.

Closes scylladb/scylladb#27964
2026-01-05 19:38:58 +02:00
Nadav Har'El
384e394ff0 Merge 'Add similarity functions to calculate similarity of given vectors' from Dawid Pawlik
It should be possible to return the similarity of vectors in CQL statements following the [Cassandra compatible syntax](https://cassandra.apache.org/doc/latest/cassandra/getting-started/vector-search-quickstart.html#query-vector-data-with-cql):

```
SELECT comment, similarity_cosine(comment_vector, [0.1, 0.15, 0.3, 0.12, 0.05])
    FROM cycling.comments_vs;
```

Although the calculations are slow, and we already have calculated results returned via Vector Store API,
we need the functionality as it allows us to calculate similarity of vectors not stored in vector indexes.

It will be needed for [quantization and rescoring](https://scylladb.atlassian.net/wiki/spaces/RND/pages/195985800/Quantization+and+Rescoring).

The feature is also a nice-to-have in testing as requested many times by testing and CX teams.

The optimized version utilizing already calculated distances from Vector Store without a need of rescoring will be coming soon after via https://github.com/scylladb/scylladb/pull/27991.

---

The patch adds functions:
- `similarity_cosine(<vector>, <vector>)`,
- `similarity_euclidean(<vector>, <vector>)`,
- `similarity_dot_product(<vector>, <vector>)`

Where `<vector>` is either a column of type `VECTOR<FLOAT, N>` or a vector of floats literal.

These functions can be called with every `SELECT` query, not only ANN vector queries as opposed to https://github.com/scylladb/scylladb/pull/25993.

The similarity calculations are implemented inspired by [USearch's implementation](
a2f1759910/include/usearch/index_plugins.hpp (L1304-L1385)) and made compatible with [Cassandra's documentation](https://cassandra.apache.org/doc/5.0/cassandra/developing/cql/functions.html#vector-similarity-functions).
That would guarantee the results in ScyllaDB are calculated using the exact same algorithms as used in Vector Store indexes.

---

Fixes: SCYLLADB-88
Fixes: SCYLLADB-89

New feature, should land into 2026.1

Closes scylladb/scylladb#27524

* github.com:scylladb/scylladb:
  docs: add vector similarity functions documentation
  test/cqlpy: add similarity functions correctness tests
  test/cqlpy: add similarity functions invalid call tests
  cql3: introduce similarity functions syntax
  vector_similarity_fcts: introduce similarity functions
  vector_similarity_fcts: retrieve similarity function argument types
  vector_similarity_fcts: add calculating similarity between vectors
2026-01-05 18:28:10 +02:00
Tomasz Grabiec
ffa11d6a2d test: Verify that repair doesn't block disabling of tablet load balancing
Refs #27647
2026-01-05 13:22:15 +01:00
Tomasz Grabiec
ccdb301731 tablets: Make balancing disabling call preempt tablet transitions
This patch modifies RESTful API handler which disables tablet
balancing to use topology request to wait for already running tablet
transitions. Before, it was just waiting for topology to be idle, so
it could wait much longer than necessary, also for operations which
are not affected by the flag, like repair. And repair can take hours.

New request type is introduced for this synchronization: noop_request.
It will preempt the tablet scheduler, and when the request executes,
we know all later tablet transitions will respect the "balancing
disabled" flag, and only things which are unuaffected by the flag,
like repair, will be scheduled.

Fixes #27647
2026-01-05 13:22:08 +01:00
Botond Dénes
e4da0afb8d reader_concurrency_semaphore: add protection against negative count resource leaks
The semaphore has detection and protection against regular resource
leaks, where some resources go unaccounted for and are not released by
the time the semaphore is destroyed. There is no detection or protection
against negative leaks: where resources are "made up" of thin air. This
kind of leaks looks benign at first sight, a few extra resources won't
hurt anyone so long as this is a small amount. But turns out that even a
single extra count resource can defeat a very important anti-deadlock
protection in can_admit_read(): the special case which admits a new
permit regardless of memory resources, when all original count resources
all available. This check uses ==, so if resource > original, the
protection is defeated indefinitely. Instead of just changing == to >=,
we add detection of such negative leaks to signal(), via
on_internal_error_noexcept().
At this time I still don't now how this negative leak happens (the code
doesn't confess), with this detection, hopefully we'll get a clue from
tests or the field. Note that on_internal_error_noexcept() will not
generate a coredump, unless ScyllaDB is explicitely configured to do so.
In production, it will just generate an error log with a backtrace.
The detection also clams the _resources to _initial_resources, to
prevent any damage from the negativae leak.

I just noticed that there is no unit test for the deadlock protection
described above, so one is added in this PR, even if only loosely
related to the rest of the patch.

Fixes: SCYLLADB-163

Closes scylladb/scylladb#27764
2026-01-05 12:45:15 +02:00
Anna Stuchlik
375479d96c doc: fix the syntax of internal links
Some internal links had the wrong syntax: they were formatted as external links.
As a result, they redirected the user to the outdated Open Source documentation.
This commit fixes that bug.

Fixes https://github.com/scylladb/scylladb/issues/25899

Closes scylladb/scylladb#27905
2026-01-05 10:44:58 +01:00
Szymon Malewski
1f658bb2e2 alternator/http_compression: Add compression of streamed response
This patch adds compression of chunked responses.
It adds intermediate stream to compress chunks of data that are provided to http sink.

Fixes #27246
2026-01-05 10:14:42 +01:00
Szymon Malewski
b8afb173a6 alternator/http_compression: Add implementation od gzip/deflate of string response
Previous commit added means to decide whether client asks for compression and with which algorithm.
This patch adds actual compression of responses based on zlib library.
For now only string (not chunked) responses are compressed.
Several previously defined tests start to pass.
2026-01-05 10:14:42 +01:00
Szymon Malewski
ec329f85b0 alternator/http_compression: Add handling of Accept-Encoding header
This is an initial patch to add support of Alternator's compressed responses.
The actual compression (gzip,deflate) will be added in the following commits.
The main functionality added in this commmit is parsing of Accept-Encoding header,
that indicates compression algorithms supported by the client.
In this commit we add also configuration parameters of response gzip/deflate compression.
They allow to enable/disable compression, set level and a size threshold below which a response is not compressed.
With current implementation it is possible to decide a compression for each response, but it is not used yet.
2026-01-05 10:14:40 +01:00
Szymon Malewski
08386ea959 test/alternator: add tests for compressed responses
Adds set of tests that:
1. Show how DynamoDB handles response compression.
It supports 'gzip' and 'deflate' compression, which can be selected by providing 'Accept-Encoding` header. It only encodes response above 4096B.
- `test_compressed_response`, `test_compressed_response_large` show compression for various response sizes.
- `test_accept_encoding_header` focuses on testing various values of Accept-Encoding header.
- `test_multiple_accept_encoding_headers` verifies behaviour with repeted Accept-Encoding headers.

2. Will confirm implementation of response compression in Alternator (#27246)
Additonally to above test, we check Altenator specific expectations:
- `test_chunked_response_compression` makes sure that compression will work also for chunked responses.
- `test_set_compression_options` checks config options to set response size threshold for compression and compression level

3. `test_signature_trims_accept_encoding_spaces` reveals Alternator's bug in signature verification (#27775)
2026-01-05 10:13:40 +01:00
Avi Kivity
0df85c8ae8 Revert "Merge 'Unify configuration of object storage endpoints' from Pavel Emelyanov"
This reverts commit 1bb897c7ca, reversing
changes made to 954f2cbd2f. It makes
incompatible changes to the object storage configuration format, breaking
tests [1]. It's likely that it doesn't break any production configuration,
but we can't be sure.

Fixes #27966

Closes scylladb/scylladb#27969
2026-01-05 08:53:41 +02:00
Benny Halevy
a8114f9bcc test_backup: do_abort_restore: reduce data footprint
To make the test fast, in particular in debug mode
insert fewer keys and do not rely on os.urandom
which is notoriously slow

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-05 08:04:08 +02:00
Benny Halevy
c0dd662144 test_backup: do_abort_restore: use error injection
Currently the test depends on timing and enough inserted
data to abort the restore tasks at exactly the right time.
This is flaky in nature, so instead, use error injection
to synchronize the abort with mutation streaming.

Note that with that we no longer get the STREAM_MUTATION_FRAGMENTS
log message, so waiting for it is dropped from the test.
The most imporant thing is that some restore tasks must fail.
(We cannot guarantee all would fail unfortunately)

Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
2026-01-05 08:03:53 +02:00