Commit Graph

51930 Commits

Author SHA1 Message Date
Marcin Maliszkiewicz
741969cf4c test: boost: add auth cache tests
The cache is covered already with general auth
dtests but some cases are more tricky and easier
to express directly as calls to cache class.
For such tests boost test file was added.
2026-02-17 18:18:40 +01:00
Marcin Maliszkiewicz
c11eb73a59 auth: add cache size metrics 2026-02-17 18:18:40 +01:00
Marcin Maliszkiewicz
a059798de9 docs: conf: update permissions cache documentation 2026-02-17 18:18:40 +01:00
Marcin Maliszkiewicz
a23e503e7b auth: remove old permissions cache 2026-02-17 17:56:27 +01:00
Marcin Maliszkiewicz
9d9184e5b7 auth: use unified cache for permissions 2026-02-17 17:56:27 +01:00
Marcin Maliszkiewicz
7eedf50c12 auth: ldap: add permissions reload to unified cache
The LDAP server may change role-chain assignments without notifying
Scylla. As a result, effective permissions can change, so some form of
polling is required.

Currently, this is handled via cache expiration. However, the unified
cache is designed to be consistent and does not support expiration.
To provide an equivalent mechanism for LDAP, we will periodically
reload the permissions portion of the new cache at intervals matching
the previously configured expiration time.
2026-02-17 17:56:27 +01:00
Marcin Maliszkiewicz
10996bd0fb auth: add permissions cache to auth/cache
We want to get rid of loading cache because its periodic
refresh logic generates a lot of internal load when there
is many entries. Also our operation procedures involve tweaking
the config while new unified cache is supposed to work out
of the box.
2026-02-17 17:56:27 +01:00
Marcin Maliszkiewicz
03c4e4bb10 auth: add service::revoke_all as main entry point
In the following commit we'll need to add some
cache related logic (removing resource permissions).
This logic doesn't depend on authorizer so it should
be managed by the service itself.
2026-02-17 17:56:27 +01:00
Marcin Maliszkiewicz
070d0bfc4c auth: explicitly life-extend resource in auth_migration_listener
Otherwise it's easy to trigger use-after-free when code slightly changes.
2026-02-17 17:56:27 +01:00
Łukasz Paszkowski
f45465b9f6 test_out_of_space_prevention.py: Lower the critical disk utilization threshold
After PR https://github.com/scylladb/scylladb/pull/28396 reduced
the test volumes to 20MiB to speed up test_out_of_space_prevention.py,
keeping the original 0.8 critical disk utilization threshold can make
the tests flaky: transient disk usage (e.g. commitlog segment churn)
can push the node into ENOSPC during the run.

These tests do not write much data, so reduce the critical disk
utilization threshold to 0.5. With 20MiB volumes this leaves ~10MiB
of headroom for temporary growth during the test.

Fixes: https://github.com/scylladb/scylladb/issues/28463

Closes scylladb/scylladb#28593
2026-02-16 15:10:18 +02:00
Andrei Chekun
e26cf0b2d6 test/cluster: fix two flaky tests
test_maintenance_socket with new way of running is flaky. Looks like the
driver tries to reconnect with an old maintenance socket from previous
driver and fails. This PR adds white list for connection that stabilize
the test
test_no_removed_node_event_on_ip_change was flaky on CI, while the issue
never reproduced locally. The assumption that under load we have race
condition and trying to check the logs before message is arrived. Small
for loop to retry added to avoid such situation.

Closes scylladb/scylladb#28635
2026-02-16 14:50:54 +02:00
Patryk Jędrzejczak
0693091aff test: test_restart_leaving_replica_during_cleanup: reconnect driver after restart
The test can currently fail like this:
```
>           await cql.run_async(f"ALTER TABLE {ks}.test WITH tablets = {{'min_tablet_count': 1}}")
E           cassandra.cluster.NoHostAvailable: ('Unable to complete the operation against any hosts', {<Host: 127.158.27.9:9042 datacenter1>: <Error from server: code=0000 [Server error] message="Failed to apply group 0 change due to concurrent modification">})
```
The following happens:
- node A is restarted and becomes the group0 leader,
- the driver sends the ALTER TABLE request to node B,
- the request hits group 0 concurrent modification error 10 times and fails
  because node A performs tablet migrations at the the same time.

What is unexpected is that even though the driver session uses the default
retry policy, the driver doesn't retry the request on node A. The request
is guaranteed to succeed on node A because it's the only node adding group0
entries.

The driver doesn't retry the request on node A because of a missing
`wait_for_cql_and_get_hosts` call. We add it in this commit. We also reconnect
the driver just in case to prevent hitting scylladb/python-driver#295.

Moreover, we can revert the workaround from
4c9efc08d8, as the fix from this commit also
prevents DROP KEYSPACE failures.

The commit has been tested in byo with `_concurrent_ddl_retries{0}` to
verify that node A really can't hit group 0 concurrent modification error
and always receives the ALTER TABLE request from the driver. All 300 runs in
each build mode passed.

Fixes #25938

Closes scylladb/scylladb#28632
2026-02-16 12:56:18 +01:00
Marcin Maliszkiewicz
6a4aef28ae Merge 'test: explicitly set compression algorithm in test_autoretrain_dict' from Andrzej Jackowski
When `test_autoretrain_dict` was originally written, the default
`sstable_compression_user_table_options` was `LZ4Compressor`. The
test assumed (correctly) that initially the compression doesn't use
a trained dictionary, and later in the test scenario, it changed
the algorithm to one with a dictionary.

However, the default `sstable_compression_user_table_options` is now
`LZ4WithDictsCompressor`, so the old assumption is no longer correct.
As a result, the assertion that data is initially not compressed well
may or may not fail depending on dictionary training timing.

To fix this, this commit explicitly sets `ZstdCompressor`
as the initial `sstable_compression_user_table_options`, ensuring that
the assumption that initial compression is without a dictionary
is always met.

Note: `ZstdCompressor` differs from the former default `LZ4Compressor`.
However, it's a better choice — the test aims to show the benefit of
using a dictionary, not the benefit of Zstd over LZ4 (and the test uses
ZstdWithDictsCompressor as the algorithm with the dictionary).

Fixes: https://github.com/scylladb/scylladb/issues/28204
Backport: 2025.4, as test already failed there (and also backport to 2026.1 to make everything consistent).

Closes scylladb/scylladb#28625

* github.com:scylladb/scylladb:
  test: explicitly set compression algorithm in test_autoretrain_dict
  test: remove unneeded semicolons from python test
2026-02-16 11:38:24 +01:00
Ernest Zaslavsky
034c6fbd87 s3_client: limit multipart upload concurrency
Prevent launching hundreds or thousands of fibers during multipart uploads
by capping concurrent part submissions to 16.

Closes scylladb/scylladb#28554
2026-02-16 13:32:58 +03:00
Botond Dénes
9f57d6285b Merge 'test: improve error reporting and retries in get_scylla_2025_1_executable' from Marcin Maliszkiewicz
Harden get_scylla_2025_1_executable() by improving error reporting when subprocesses fail,
increasing curl's retry count for more resilient downloads, and enabling --retry-all-errors to retry on all failures.

Fixes https://github.com/scylladb/scylladb/issues/27745
Backport: no, it's not a bug fix

Closes scylladb/scylladb#28628

* github.com:scylladb/scylladb:
  test: pylib: retry on all errors in get_scylla_2025_1_executable curl's call
  test: pylib: increase curl's number of retries when downloading scylla
  test: pylib: improve error reporting in get_scylla_2025_1_executable
2026-02-16 10:09:17 +02:00
Andrei Chekun
8c5c1096c2 test: ensure that that table used it cqlpy/test_tools have at least 3 pk
One of the tests check that amount of the PK should be more than 2, but
the method that creates it can return table with less keys. This leads
to flakiness and to avoid it, this PR ensures that table will have at
least 3 PK

Closes scylladb/scylladb#28636
2026-02-16 09:50:58 +02:00
Anna Mikhlin
33cf97d688 .github/workflows: ignore quoted comments for trigger CI
prevent CI from being triggered when trigger-ci command appears inside
quoted (>) comment text

Fixes: https://scylladb.atlassian.net/browse/RELENG-271

Closes scylladb/scylladb#28604
2026-02-16 09:33:16 +02:00
Andrei Chekun
e144d5b0bb test.py: fix JUnit double test case records
Move the hook for overwriting the XML reporter to be the first, to
avoid double records.

Closes scylladb/scylladb#28627
2026-02-15 19:02:24 +02:00
Jenkins Promoter
69249671a7 Update pgo profiles - aarch64 2026-02-15 05:22:17 +02:00
Jenkins Promoter
27aaafb8aa Update pgo profiles - x86_64 2026-02-15 04:26:36 +02:00
Piotr Dulikowski
9c1e310b0d Merge 'vector_search: Fix flaky vector_store_client_https_rewrite_ca_cert' from Karol Nowacki
Most likely, the root cause of the flaky test was that the TLS handshake hung for an extended period (60s). This caused
the test case to fail because the ANN request duration exceeded the test case timeout.

The PR introduces two changes:

* Mitigation of the hanging TLS handshake: This issue likely occurred because the test performed certificate rewrites
simultaneously with ANN requests that utilize those certificates.
* Production code fix: This addresses a bug where the TLS handshake itself was not covered by the connection timeout.
Since tls::connect does not perform the handshake immediately, the handshake only occurs during the first write
operation, potentially bypassing connect timeout.

Fixes: #28012

Backport to 2026.01 and 2025.04 is needed, as these branches are also affected and may experience CI flakiness due to this test.

Closes scylladb/scylladb#28617

* github.com:scylladb/scylladb:
  vector_search: Fix missing timeout on TLS handshake
  vector_search: test: Fix flaky cert rewrite test
2026-02-13 19:03:50 +01:00
Marcin Maliszkiewicz
1b0a68d1de test: pylib: retry on all errors in get_scylla_2025_1_executable curl's call
It's difficult to say if our download backend would always return
transient error correctly so that the curl could retry. Instead it's
more robust to always retry on error.
2026-02-12 16:18:52 +01:00
Marcin Maliszkiewicz
8ca834d4a4 test: pylib: increase curl's number of retries when downloading scylla
By default curl does exponential backoff, and we want to keep that
but there is time cap of 10 minutes, so with 40 retries we'd wait
long time, instead we set the cap to 60 seconds.

Total waiting time (excluding receiving request time):
before - 17m
after - 35m
2026-02-12 16:18:52 +01:00
Marcin Maliszkiewicz
70366168aa test: pylib: improve error reporting in get_scylla_2025_1_executable
Curl or other tools this function calls will now log error
in the place they fail instead of doing plain assert.
2026-02-12 16:18:52 +01:00
Andrzej Jackowski
9ffa62a986 test: explicitly set compression algorithm in test_autoretrain_dict
When `test_autoretrain_dict` was originally written, the default
`sstable_compression_user_table_options` was `LZ4Compressor`. The
test assumed (correctly) that initially the compression doesn't use
a trained dictionary, and later in the test scenario, it changed
the algorithm to one with a dictionary.

However, the default `sstable_compression_user_table_options` is now
`LZ4WithDictsCompressor`, so the old assumption is no longer correct.
As a result, the assertion that data is initially not compressed well
may or may not fail depending on dictionary training timing.

To fix this, this commit explicitly sets `ZstdCompressor`
as the initial `sstable_compression_user_table_options`, ensuring that
the assumption that initial compression is without a dictionary
is always met.

Note: `ZstdCompressor` differs from the former default `LZ4Compressor`.
However, it's a better choice — the test aims to show the benefit of
using a dictionary, not the benefit of Zstd over LZ4 (and the test uses
ZstdWithDictsCompressor as the algorithm with the dictionary).

Fixes: scylladb/scylladb#28204
2026-02-12 14:58:39 +01:00
Andrzej Jackowski
e63cfc38b3 test: remove unneeded semicolons from python test 2026-02-12 14:49:17 +01:00
Aleksandra Martyniuk
f955a90309 test: fix test_remove_node_violating_rf_rack_with_rack_list
test_remove_node_violating_rf_rack_with_rack_list creates a cluster
with four nodes. One of the nodes is excluded, then another one is
stopped, excluded, and removed. If the two stopped nodes were both
voters, the majority is lost and the cluster loses its raft leader.
As a result, the node cannot be removed and the operation times out.

Add the 5th node to the cluster. This way the majority is always up.

Fixes: https://github.com/scylladb/scylladb/issues/28596.

Closes scylladb/scylladb#28610
2026-02-12 12:58:48 +02:00
Ferenc Szili
4ca40929ef test: add read barrier to test_balance_empty_tablets
The test creates a single node cluster, then creates 3 tables which
remain empty. Then it adds another node with half the disk capacity of
the first one, and then it waits for the balancer to migrate tablets to
the newly added node by calling the quiesce topology API. The number of
tablets on the smaller node should be exactly half the number of tablets
on the larger node.

After waiting for quiesce topology, we could have a situation where we
query the number of tablets from the node which still hasn't processed
the last tablet migrations and updated system.tablets.

This patch adds a read barrier so that both nodes see the same tablets
metadata before we query the number of tablets.

Fixes: SCYLLADB-603

Closes scylladb/scylladb#28598
2026-02-12 11:16:34 +02:00
Karol Nowacki
079fe17e8b vector_search: Fix missing timeout on TLS handshake
Currently the TLS handshake in the vector search client does not have a timeout.
This is because tls::connect does not perform handshake itself; the handshake
is deferred until the first read/write operation is performed. This can lead to long
hangs on ANN requests.

This commit calls tls::check_session_is_resumed() after tls::connect
to force the handshake to happen immediately and to run under with_timeout.
2026-02-12 10:08:37 +01:00
Karol Nowacki
aef5ff7491 vector_search: test: Fix flaky cert rewrite test
The test is flaky most likely because when TLS certificate rewrite
happens simultaneously with an ANN request, the handshake can hang for a
long time (~60s). This leads to a timeout in the test case.

This change introduces a checkpoint in the test so that it will
wait for the certificate rewrite to happen before sending an ANN request,
which should prevent the handshake from hanging and make the test more reliable.

Fixes: #28012
2026-02-12 09:58:54 +01:00
Piotr Dulikowski
38c4a14a5b Merge 'test: cluster: Fix test_sync_point' from Dawid Mędrek
The test `test_sync_point` had a few shortcomings that made it flaky
or simply wrong:

1. We were verifying that hints were written by checking the size of
   in-flight hints. However, that could potentially lead to problems
   in rare situations.

   For instance, if all of the hints failed to be written to disk, the
   size of in-flight hints would drop to zero, but creating a sync point
   would correspond to the empty state.

   In such a situation, we should fail immediately and indicate what
   the cause was.

2. A sync point corresponds to the hints that have already been written
   to disk. The number of those is tracked by the metric `written`.
   It's a much more reliable way to make sure that hints have been
   written to the commitlog. That ensures that the sync point we'll
   create will really correspond to those hints.

3. The auxiliary function `wait_for` used in the test works like this:
   it executes the passed callback and looks at the result. If it's
   `None`, it retries it. Otherwise, the callback is deemed to have
   finished its execution and no further retries will be attempted.

   Before this commit, we simply returned a bool, and so the code was
   wrong. We improve it.

---

Note that this fixes scylladb/scylladb#28203, which was a manifestation
of scylladb/scylladb#25879. We created a sync point that corresponded
to the empty state, and so it immediately resolved, even when node 3
was still dead.

As a bonus, we rewrite the auxiliary code responsible for fetching
metrics and manipulating sync points. Now it's asynchronous and
uses the existing standard mechanisms available to developers.

Furthermore, we reduce the time needed for executing
`test_sync_point` by 27 seconds.

---

The total difference in time needed to execute the whole test file
(on my local machine, in dev mode):

Before:

    CPU utilization: 0.9%

    real    2m7.811s
    user    0m25.446s
    sys     0m16.733s

After:

    CPU utilization: 1.1%

    real    1m40.288s
    user    0m25.218s
    sys     0m16.566s

---

Refs scylladb/scylladb#25879
Fixes scylladb/scylladb#28203

Backport: This improves the stability of our CI, so let's
          backport it to all supported versions.

Closes scylladb/scylladb#28602

* github.com:scylladb/scylladb:
  test: cluster: Reduce wait time in test_sync_point
  test: cluster: Fix test_sync_point
  test: cluster: Await sync points asynchronously
  test: cluster: Create sync points asynchronously
  test: cluster: Fetch hint metrics asynchronously
2026-02-12 09:34:09 +01:00
Dawid Mędrek
f83f911bae test: cluster: Reduce wait time in test_sync_point
If everything is OK, the sync point will not resolve with node 3 dead.
As a result, the waiting will use all of the time we allocate for it,
i.e. 30 seconds. That's a lot of time.

There's no easy way to verify that the sync point will NOT resolve, but
let's at least reduce the waiting to 3 seconds. If there's a bug, it
should be enough to trigger it at some point, while reducing the average
time needed for CI.
2026-02-10 17:05:02 +01:00
Dawid Mędrek
a256ba7de0 test: cluster: Fix test_sync_point
The test had a few shortcomings that made it flaky or simply wrong:

1. We were verifying that hints were written by checking the size of
   in-flight hints. However, that could potentially lead to problems
   in rare situations.

   For instance, if all of the hints failed to be written to disk, the
   size of in-flight hints would drop to zero, but creating a sync point
   would correspond to the empty state.

   In such a situation, we should fail immediately and indicate what
   the cause was.

2. A sync point corresponds to the hints that have already been written
   to disk. The number of those is tracked by the metric `written`.
   It's a much more reliable way to make sure that hints have been
   written to the commitlog. That ensures that the sync point we'll
   create will really correspond to those hints.

3. The auxiliary function `wait_for` used in the test works like this:
   it executes the passed callback and looks at the result. If it's
   `None`, it retries it. Otherwise, the callback is deemed to have
   finished its execution and no further retries will be attempted.

   Before this commit, we simply returned a bool, and so the code was
   wrong. We improve it.

Note that this fixes scylladb/scylladb#28203, which was a manifestation
of scylladb/scylladb#25879. We created a sync point that corresponded
to the empty state, and so it immediately resolved, even when node 3
was still dead.

Refs scylladb/scylladb#25879
Fixes scylladb/scylladb#28203
2026-02-10 17:05:02 +01:00
Dawid Mędrek
c5239edf2a test: cluster: Await sync points asynchronously
There's a dedicated HTTP API for communicating with the cluster, so
let's use it instead of yet another custom solution.
2026-02-10 17:05:02 +01:00
Dawid Mędrek
ac4af5f461 test: cluster: Create sync points asynchronously
There's a dedicated HTTP API for communicating with the nodes, so let's
use it instead of yet another custom solution.
2026-02-10 17:05:01 +01:00
Dawid Mędrek
628e74f157 test: cluster: Fetch hint metrics asynchronously
There's a dedicated API for fetching metrics now. Let's use it instead
of developing yet another solution that's also worse.
2026-02-10 17:04:59 +01:00
Pawel Pery
81d11a23ce Revert "Merge 'vector_search: add validator tests' from Pawel Pery"
This reverts commit bcd1758911, reversing
changes made to b2c2a99741.

There is a design decision to not introduce additional test
orchestration tool for scylladb.git (see comments for #27499). One
commit has already been reverted in 55c7bc7. Last CI runs made validator
test flaky, so it is a time to remove all remaining validator tests.

It needs a backport to 2026.1 to remove remaining validator tests from there.

Fixes: VECTOR-497

Closes scylladb/scylladb#28568
2026-02-08 16:29:58 +02:00
Avi Kivity
bb99bfe815 test: scylla_gdb: tighten check for Error output from gdb
When running a gdb command, we check that the string 'Error'
does not appear within the output. However, if the command output
includes the string 'Error' as part of its normal operation, this
generates a false positive. In fact the task_histogram can include
the string 'error::Error' from the Rust core::error module.

Allow for that and only match 'Error' that isn't 'error::Error'.

Fixes #28516.

Closes scylladb/scylladb#28574
2026-02-08 09:48:23 +02:00
Anna Stuchlik
dc8f7c9d62 doc: replace the OS Support page with a link to the new location
We've moved that page to another place; see https://github.com/scylladb/scylladb/issues/28561.
This commit replaces the page with the link to the new location
and adds a redirection.

Fixes https://github.com/scylladb/scylladb/issues/28561

Closes scylladb/scylladb#28562
2026-02-06 11:38:21 +02:00
Avi Kivity
7a3ce5f91e test: minio: disable web console
minio starts a web console on a random port. This was seen to interfere
with the nodetool tests when the web console port clashed with the mock
API port.

Fix by disabling the web console.

Fixes https://scylladb.atlassian.net/browse/SCYLLADB-496

Closes scylladb/scylladb#28492
2026-02-05 20:11:32 +02:00
Nikos Dragazis
5d1e6243af test/cluster: Remove short_tablet_stats_refresh_interval injection
The test `test_size_based_load_balancing.py::test_balance_empty_tablets`
waits for tablet load stats to be refreshed and uses the
`short_tablet_stats_refresh_interval` injection to speed up the refresh
interval.

This injection has no effect; it was replaced by the
`tablet_load_stats_refresh_interval_in_seconds` config option (patch: 1d6808aec4),
so the test currently waits for 60 seconds (default refresh interval).

Use the config option. This reduces the execution time to ~8 seconds.

Fixes SCYLLADB-556.

Signed-off-by: Nikos Dragazis <nikolaos.dragazis@scylladb.com>

Closes scylladb/scylladb#28536
2026-02-05 20:11:32 +02:00
Pavel Emelyanov
10c278fff7 database: Remove _flush_sg member from replica::database
This field is only used to initialize the following _memtable_controller
one. It's simpler just to do the initialization with whatever value the
field itself is initialized and drop the field itself.

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

Closes scylladb/scylladb#28539
2026-02-05 13:02:35 +02:00
Petr Hála
a04dbac369 open-coredump: Change to use new backtrace
* This is a breaking change, which removes compatibility with the old backtrace
    - See https://staging.backtrace.scylladb.com/api/docs#/default/search_by_build_id_search_build_id_post for the APIDoc
* Add timestamp field to log
* Tested locally

Closes scylladb/scylladb#28325
2026-02-05 11:50:47 +02:00
Marcin Maliszkiewicz
0753d9fae5 Merge 'test: remove xfail marker from a few passing tests' from Nadav Har'El
This patch fixes the few remaining cases of XPASS in test/cqlpy and test/alternator.
These are tests which, when written, reproduced a bug and therefore were marked "xfail", but some time later the bug was fixed and we either did not notice it was ever fixed, or just forgot to remove the xfail marker.

Removing the no-longer-needed xfail markers is good for test hygiene, but more importantly is needed to avoid regressions in those already-fixed areas (if a test is already marked xfail, it can start to fail in a new way and we wouldn't notice).

Backport not needed, xpass doesn't bother anyone.

Closes scylladb/scylladb#28441

* github.com:scylladb/scylladb:
  test/cqlpy: remove xfail from tests for fixed issue 7972
  test/cqlpy: remove xfail from tests for fixed issue 10358
  test/cqlpy: remove xfail from passing test testInvalidNonFrozenUDTRelation
  test/alternator: remove xfail from passing test_update_item_increases_metrics_for_new_item_size_only
2026-02-05 10:10:43 +01:00
Marcin Maliszkiewicz
6eca74b7bb Merge 'More Alternator tests for BatchWriteItem' from Nadav Har'El
The goal of this small pull request is to reproduce issue #28439, which found a bug in the Alternator Streams output when BatchWriteItem is called to write multiple items in the same partition, and always_use_lwt write isolation mode is used.

* The first patch reproduces this specific bug in Alternator Streams.
* The second patch adds missing (Fixes #28171) tests for BatchWriteItem in different write modes, and shows that BatchWriteItem itself works correctly - the bug is just in Alternator Streams' reporting of this write.

Closes scylladb/scylladb#28528

* github.com:scylladb/scylladb:
  test/alternator: add test for BatchWriteItem with different write isolations
  test/alternator: reproducer for Alternator Streams bug
2026-02-05 10:07:29 +01:00
Yaron Kaikov
b30ecb72d5 ci: fix PR number extraction for unlabeled events
When the workflow is triggered by removing the 'conflicts' label
(pull_request_target unlabeled event), github.event.issue.number is
not available. Use github.event.pull_request.number as fallback.

Fixes: https://scylladb.atlassian.net/browse/RELENG-245

Closes scylladb/scylladb#28543
2026-02-05 08:41:43 +02:00
Michał Hudobski
6b9fcc6ca3 auth: add CDC streams and timestamps to vector search permissions
It turns out that the cdc driver requires permissions to two additional system tables. This patch adds them to VECTOR_SEARCH_INDEXING and modifies the unit tests. The integration with vector store was tested manually, integration tests will be added in vector-store repository in a follow up PR.

Fixes: SCYLLADB-522

Closes scylladb/scylladb#28519
2026-02-04 09:10:08 +01:00
Nadav Har'El
47e827262f test/alternator: add test for BatchWriteItem with different write isolations
Alternator's various write operations have different code paths for the
different write isolation modes. Because most of the test suite runs in
only a single write mode (currently - only_rmw_uses_lwt), we already
introduced a test file test/alternator/test_write_isolation.py for
checking the different write operations in *all* four write isolation
modes.

But we missed testing one write operation - BatchWriteItem. This
operation isn't very "interesting" because it doesn't support *any*
read-modify-option option (it doesn't support UpdateExpression,
ConditionExpression or ReturnValues), but even without those, the
pure write code still has different code paths with and without LWT,
and should be tested. So we add the missing test here - and it passes.

In issue #28439 we discovered a bug that can be seen in Alternator
Streams in the case of BatchWriteItem with multiple writes to the
same partition and always_use_lwt mode. The fact that the test added
here passes shows that the bug is NOT in BatchWriteItem itself, which
works correctly in this case - but only in the Alternator Streams layer.

Fixes #28171

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
2026-02-04 09:24:29 +02:00
Nadav Har'El
c63f43975f test/alternator: reproducer for Alternator Streams bug
This patch adds a reproducer for an Alternator Streams bug described in
issue #28439, where the stream returns the wrong events (and fewer of
them) in the following specific combination of the following circumstances:

1. A BatchWriteItem operation writing multiple items to the *same*
   partition.

2. The "always_use_lwt" write isolation mode is used. (the bug doesn't
   occur in other write isolation modes).

We didn't catch this bug earlier because the Alternator Streams test
we had for BatchWriteItem had multiple items in multiple partitions,
and we missed the multiple-items-in-one-partition case. Moreover,
today we run all the tests in only_rmw_uses_lwt mode (in the past,
we did use always_use_lwt, but changed recently in commit e7257b1393
following commit 76a766c that changed test.py).

As issue #28439 explains, the underlying cause of the bug is that the
always_use_lwt causes the multiple items to be written with the same
timestamp, which confused the Alternator Streams code reading the CDC
log. The bug is not in BatchWriteItem itself, or in ScyllaDB CDC, but
just in the Alternator Streams layer.

The test in this patch is parameterized to run on each of the four
write isolation modes, and currently fails (and so marked xfail) just
for the one mode 'always_use_lwt'. The test is scylla_only, as its
purpose is to checks the different write isolation mode - which don't
exist in AWS DynamoDB.

Refs #28439

Signed-off-by: Nadav Har'El <nyh@scylladb.com>
2026-02-04 09:17:48 +02:00
Radosław Cybulski
03ff091bee alternator: improve events output when test failed
Improve events printing, when test in test_streams.py failed.
New code will print both expected and received events (keys, previous
image, new image and type).
New code will explicitly mark, at which output event comparison failed.

Fixes #28455

Closes scylladb/scylladb#28476
2026-02-03 21:55:07 +02:00