Commit Graph

69 Commits

Author SHA1 Message Date
Michał Jadwiszczak
5c84cff78a test/cluster/mv/test_mv_building: add similar test for vnode-based view
In the dtest repo, the test run for both vnode and tablet based views.

Since in test.py infra we're using error injection to pause the view
building process, we need separate tests for those two cases.
2026-05-14 10:52:44 +02:00
Wojciech Mitros
f3cf20803b test: run test_mv_admission_control_exception on one shard
In the test we perform 2 consecutive writes where the first write
is supposed to increase the view update backlog above the mv
admission control threshold and the second one is expected to be
rejected because of that.

On each node/shard we have 2 types of view update backlogs:
 1. for deciding whether we should admit writes
 2. for propagating the backlog information to other nodes/shards.

For the second write to be rejected, it must be performed on a node
and shard which updated its backlog of type 1.

The view update backlog of type 2. is immediately increased on the
base table replica. For this backlog to be registered as a backlog
of type 1., it needs to be either carried by gossip (happening once
every second) or by attaching it to a replica write response. We
don't want to increase the runtime of tests unnecessarily, so we don't
wait and we rely on the second mechanism. The response to the first
base table write (the one causing increase in the backlog) carries
the increased backlog to the coordinator of this write. So for the
second write to observe the increased backlog, it needs to be coordinated
on the same node+shard as the first write.

We make sure that both writes are coordinated on the same node+shard by
using prepared statements combined with setting the host in `run_async`.
Both writes target the same partition and with prepared statements we
route them directly to the correct shard.

That was the idea, at least. In practice, for the driver to learn the
correct shard, it first needs to learn the token->shard mapping from
the server. For vnodes it can expect a shard by calculating the token
of the affected partition, but for tablets, it had no opportunity to
learn the tablet->shard mapping so the first write may route to any shard.
Additionally, we aren't guaranteed that the driver established connections
to all shards on all nodes at the point of any write. So if a connection
finishes establishing between the two writes, this may also cause us to
coordinate these 2 writes on different shards, leading to a missed view
backlog growth and not-rejected second write.

We fix this in this patch by running the test using one shard on each node.
This way, as long as we perform both writes on the same node, they'll also
be coordinated on the same shard. This also makes the prepared statement and
BoundStatement unnecessary — we can use SimpleStatement with
FallthroughRetryPolicy directly.

Fixes: SCYLLADB-1901

Closes scylladb/scylladb#29862
2026-05-12 17:34:19 +02:00
Wojciech Mitros
ab12083525 test: propagate view update backlog before partition delete
In the test_delete_partition_rows_from_table_with_mv case we perform
a deletion of a large partition to verify that the deletion will
self-throttle when generating many view updates.
Before the deletion, we first build the materialized view, which causes
the view update backlog to grow. The backlog should be back to empty
when the view building finishes, and we do wait for that to happen, but
the information about the backlog drop may not be propagated to the
delete coordinator in time - the gossip interval is 1s and we perform
no other writes between the nodes in the meantime, so we don't make use
of the "piggyback" mechanism of propagating view backlog either. If the
coordinator thinks that the backlog is high on the replica, it may reject
the delete, failing this test.
We change this in this patch - after the view is built, we perform an
extra write from the coordinator. When the write finishes, the coordinator
will have the up-to-date view backlog and can proceed with the DELETE.
Additionally, we enable the "update_backlog_immediately" injection, which
makes the node backlog (the highest backlog across shards) update immediately
after each change.

Fixes: SCYLLADB-1795

Closes scylladb/scylladb#29775
2026-05-07 11:33:13 +03:00
Michael Litvak
3468e8de8b test/mv/test_mv_staging: wait for cql after restart
Wait for cql on all hosts after restarting a server in the test.

The problem that was observed is that the test restarts servers[1] and
doesn't wait for the cql to be ready on it. On test teardown it drops
the keyspace, trying to execute it on the host that is not ready, and
fails.

Fixes SCYLLADB-1632

Closes scylladb/scylladb#29562
2026-04-23 12:40:19 +02:00
Botond Dénes
eb3326b417 Merge 'test.py: migrate all bare skips to typed skip markers' from Artsiom Mishuta
should be merged after #29235

Complete the typed skip markers migration started in the plugin PR.
Every bare `@pytest.mark.skip` decorator and `pytest.skip()` runtime call
across the test suite is replaced with a typed equivalent, making skip
reasons machine-readable in JUnit XML and Allure reports.

**62 files changed** across 8 commits, covering ~127 skip sites in total.

Bare `pytest.skip` provides only a free-text reason string. CI dashboards
(JUnit, Allure) cannot distinguish between a test skipped due to a known
bug, a missing feature, a slow test, or an environment limitation. This
makes it hard to track skip debt, prioritize fixes, or filter dashboards
by skip category.

The typed markers (`skip_bug`, `skip_not_implemented`, `skip_slow`,
`skip_env`) introduced by the `skip_reason_plugin` solve this by embedding
a `skip_type` field into every skip report entry.

| Type | Count | Files | Description |
|------|-------|-------|-------------|
| `skip_bug` | 24 | 16 | Skip reason references a known bug/issue |
| `skip_not_implemented` | 10 | 5 | Feature not yet implemented in Scylla |
| `skip_slow` | 4 | 3 | Test too slow for regular CI runs |
| `skip_not_implemented` (bare) | 2 | 1 | Bare `@pytest.mark.skip` with no reason (COMPACT STORAGE, #3882) |

| Type | Count | Files | Description |
|------|-------|-------|-------------|
| `skip_env` | ~85 | 34 | Feature/config/topology not available at runtime |
| `skip_bug` | 2 | 2 | Known bugs: Streams on tablets (#23838), coroutine task not found (#22501) |

- **Comments**: 7 comments/docstrings across 5 files updated from `pytest.skip()` to `skip()`
- **Plugin hardened**: `warnings.warn()` → `pytest.UsageError` for bare `@pytest.mark.skip` at collection time — bare skips are now a hard error, not a warning
- **Guard tests**: New `test/pylib_test/test_no_bare_skips.py` with 3 tests that prevent regression:
  - AST scan for bare `@pytest.mark.skip` decorators
  - AST scan for bare `pytest.skip()` runtime calls
  - Real `pytest --collect-only` against all Python test directories

Runtime skip sites use the convenience wrappers from `test.pylib.skip_types`:
```python
from test.pylib.skip_types import skip_env
```

Usage:
```python
skip_env("Tablets not enabled")
```

1. **test: migrate @pytest.mark.skip to @pytest.mark.skip_bug for known bugs** — 24 decorator sites, 16 files
2. **test: migrate @pytest.mark.skip to @pytest.mark.skip_not_implemented** — 10 decorator sites, 5 files
3. **test: migrate @pytest.mark.skip to @pytest.mark.skip_slow** — 4 decorator sites, 3 files
4. **test: migrate bare @pytest.mark.skip to skip_not_implemented** — 2 bare decorators, 1 file
5. **test: migrate runtime pytest.skip() to typed skip_env()** — ~85 sites, 34 files
6. **test: migrate runtime pytest.skip() to typed skip_bug()** — 2 sites, 2 files
7. **test: update comments referencing pytest.skip() to skip()** — 7 comments, 5 files
8. **test/pylib: reject bare pytest.mark.skip and add codebase guards** — plugin hardening + 3 guard tests

- All 60 plugin + guard tests pass (`test/pylib_test/`)
- No bare `@pytest.mark.skip` or `pytest.skip()` calls remain in the codebase
- `pytest --collect-only` succeeds across all test directories with the hardened plugin

SCYLLADB-1349

Closes scylladb/scylladb#29305

* github.com:scylladb/scylladb:
  test/alternator: replace bare pytest.skip() with typed skip helpers
  test: migrate new bare skips introduced by upstream after rebase
  test/pylib: reject bare pytest.mark.skip and add codebase guards
  test: update comments referencing pytest.skip() to skip_env()
  test: migrate runtime pytest.skip() to typed skip_bug()
  test: migrate runtime pytest.skip() to typed skip_env()
  test: migrate bare @pytest.mark.skip to skip_not_implemented
  test: migrate @pytest.mark.skip to @pytest.mark.skip_slow
  test: migrate @pytest.mark.skip to @pytest.mark.skip_not_implemented
  test: migrate @pytest.mark.skip to @pytest.mark.skip_bug for known bugs
2026-04-22 15:48:27 +03:00
Tomasz Grabiec
cddde464ca Merge 'service: Support adding/removing a datacenter with tablets by changing RF' from Aleksandra Martyniuk
With this change, you can add or remove a DC(s) in a single ALTER KEYSPACE statement. It requires the keyspace to use rack list replication factor.

In existing approach, during RF change all tablet replicas are rebuilt at once. This isn't the case now. In global_topology_request::keyspace_rf_change the request is added to a ongoing_rf_changes - a new column in system.topology table. In a new column in system_schema.keyspaces - next_replication - we keep the target RF.

In make_rf_change_plan, load balancer schedules necessary migrations, considering the load of nodes and other pending tablet transitions. Requests from ongoing_rf_changes are processed concurrently, independently from one another. In each request racks are processed concurrently. No tablet replica will be removed until all required replicas are added. While adding replicas to each rack we always start with base tables and won't proceed with views until they are done (while removing - the other way around). The intermediary steps aren't reflected in schema. When the Rf change is finished:
- in system_schema.keyspaces:
  - next_replication is cleared;
  - new keyspace properties are saved;
- request is removed from ongoing_rf_changes;
- the request is marked as done in system.topology_requests.

Until the request is done, DESCRIBE KEYSPACE shows the replication_v2.

If a request hasn't started to remove replicas, it can be aborted using task manager. system.topology_requests::error is set (but the request isn't marked as done) and next_replication = replication_v2. This will be interpreted by load balancer, that will start the rollback of the request. After the rollback is done, we set the relevant system.topology_requests entry as done (failed), clear the request id from system.topology::ongoing_rf_changes, and remove next_replication.

Fixes: SCYLLADB-567.

No backport needed; new feature.

Closes scylladb/scylladb#24421

* github.com:scylladb/scylladb:
  service: fix indentation
  docs: update documentation
  test: test multi RF changes
  service: tasks: allow aborting ongoing RF changes
  cql3: allow changing RF by more than one when adding or removing a DC
  service: handle multi_rf_change
  service: implement make_rf_change_plan
  service: add keyspace_rf_change_plan to migration_plan
  service: extend tablet_migration_info to handle rebuilds
  service: split update_node_load_on_migration
  service: rearrange keyspace_rf_change handler
  db: add columns to system_schema.keyspaces
  db: service: add ongoing_rf_changes to system.topology
  gms: add keyspace_multi_rf_change feature
2026-04-22 01:46:11 +02:00
Łukasz Paszkowski
d18eb9479f cql/statement: Create keyspace_metadata with correct initial_tablets count
In `ks_prop_defs::as_ks_metadata(...)` a default initial tablets count
is set to 0, when tablets are enabled and the replication strategy
is NetworkReplicationStrategy.

This effectively sets _uses_tablets = false in abstract_replication_strategy
for the remaining strategies when no `tablets = {...}` options are specified.
As a consequence, it is possible to create vnode-based keyspaces even
when tablets are enforced with `tablets_mode_for_new_keyspaces`.

The patch sets a default initial tablets count to zero regardless of
the chosen replication strategy. Then each of the replication strategy
validates the options and raises a configuration exception when tablets
are not supported.

All tests are altered in the following way:
+ whenever it was correct, SimpleStrategy was replaced with NetworkTopologyStrategy
+ otherwise, tablets were explicitly disabled with ` AND tablets = {'enabled': false}`

Fixes https://github.com/scylladb/scylladb/issues/25340

Closes scylladb/scylladb#25342
2026-04-20 17:57:38 +03:00
Artsiom Mishuta
465636bc53 test: migrate @pytest.mark.skip to @pytest.mark.skip_bug for known bugs
Migrate 24 @pytest.mark.skip decorator sites to @pytest.mark.skip_bug
across 16 test files where the reason references a known bug or issue.
2026-04-19 11:06:30 +02:00
Aleksandra Martyniuk
38bad5f316 cql3: allow changing RF by more than one when adding or removing a DC
rf_rack_valid_keyspaces relies on the fact that replicas of base
table and mv are streamed concurrently. This is no longer true
for newly introduced method of adding a DC. Disable rf_rack_valid_keyspaces
in test_mv_first_replica_in_dc to force the old method.
2026-04-17 09:58:08 +02:00
Avi Kivity
0ae22a09d4 LICENSE: Update to version 1.1
Updated terms of non-commercial use (must be a never-customer).
2026-04-12 19:46:33 +03:00
Michael Litvak
399260a6c0 test: mv: fix flaky wait for commitlog sync
Previously the test test_interrupt_view_build_shard_registration stopped
the node ungracefully and used commitlog periodic mode to persist the
view build progress in a not very reliable way.

It can happen that due to timing issues, the view build progress is not
persisted, or some of it is persisted in a different ordering than
expected.

To make the test more reliable we change it to stop the node gracefully,
so the commitlog is persisted in a graceful and consistent way, without
using the periodic mode delay. We need to also change the injection for
the shutdown to not get stuck.

Fixes SCYLLADB-1005

Closes scylladb/scylladb#29008
2026-03-19 10:41:21 +01:00
Piotr Dulikowski
a2669e9983 test: test_mv_merge_allowed: add mistakenly omitted awaits
The test test_mv_merge_allowed asserts in two places that the tablet
count is 2. It does so by calling an async function but, mistakenly, the
returned coroutine was not awaited. The coroutine is, apparently, truthy
so the assertions always passed.

Fix the test to properly await the coroutines in the assertions.

Fixes: SCYLLADB-905

Closes scylladb/scylladb#28875
2026-03-05 11:29:23 +01:00
Michael Litvak
8c4bc33e51 test: remove test_view_building_with_tablet_move
remove the test since it's not relevant anymore, it's not testing what
it's supposed to test and it's unstable.

the purpose of the test was to reproduce an issue in the legacy view
builder where a view starts to build at token T2 and then all tokens
[T1, end) with T1<T2 migrate to another node while it's still building,
exposing an issue when the view builder wraparounds the token ring.

this is not relevant anymore because now view building with tablets is
done via the view building coordinator for tablets, and all views start
to build from the first token with no wraparound.

besides, the test is unstable due to relying too much on specific
timing, which was useful for investigating and fixing the original issue
but not anymore.

Fixes SCYLLADB-842

Closes scylladb/scylladb#28842
2026-03-02 07:42:08 +01:00
Alex
5557770b59 test_mv_build_during_shutdown started two async CREATE MATERIALIZED VIEW operations and never awaited them (asyncio.gather(...) without await).
This pr adds await for each one of the tasks to wait for the MV schema to be added successfully
and then to start the server shutdown
With this change we dont need will not get the shutdown races.

Closes scylladb/scylladb#28774
2026-02-24 17:25:05 +01:00
Botond Dénes
b637e17b19 db/config: don't use RBNO for scaling
Remove bootstrap and decomission from allowed_repair_based_node_ops.
Using RBNO over streaming for these operations has no benefits, as they
are not exposed to the out-of-date replica problem that replace,
removenode and rebuild are.
On top of that, RBNO is known to have problems with empty user tables.
Using streaming for boostrap and decomission is safe and faster
than RBNO in all condition, especially when the table is small.

One test needs adjustment as it relies on RBNO being used for all node
ops.

Fixes: SCYLLADB-105

Closes scylladb/scylladb#28080
2026-02-19 09:51:09 +01:00
Gleb Natapov
08268eee3f topology: disable force-gossip-topology-changes option
The patch marks force-gossip-topology-changes as deprecated and removes
tests that use it. There is one test (test_different_group0_ids) which
is marked as xfail instead since it looks like gossiper mode was used
there as a way to easily achieve a certain state, so more investigation
is needed if the tests can be fixed to use raft mode instead.

Closes scylladb/scylladb#28383
2026-02-02 09:56:32 +01:00
Andrei Chekun
cc5ac75d73 test.py: remove deprecated skip_mode decorator
Finishing the deprecation of the skip_mode function in favor of
pytest.mark.skip_mode. This PR is only cleaning and migrating leftover tests
that are still used and old way of skip_mode.

Closes scylladb/scylladb#28299
2026-01-25 18:17:27 +02:00
Tomasz Grabiec
d3ee82ea51 topology_coordinator, storage_service: Validate node removal/decommission at request submission time
After parallel tablet draining, the validation at the time request
starts executing is too late, tablets will be already drained.

This trips tests which expect validation failure, but get tablet
draining failure instead.

Also, in case of decommission, it's a waste to go through draining
only to discover that the operation has to be rolled back due to
validation.

So avoid submitting a request altogether if it's invalid.
The validation at request execution start remains, for extra sefety.

validate_removing_node() was extracted out of topology_coordinator,
so that it can be called by storage_service on non-coordinator.

Some tests need adjusting for the fact that after failed removenode
the node may still not be marked as excluded, so we need to explicitly
exclude it or add to the list of ignored nodes in the next removenode
operation.
2026-01-18 15:36:04 +01:00
Tomasz Grabiec
5e6935f276 test: Use ManagerClient.{disable,enable}_tablet_balancing() 2026-01-13 00:38:00 +01:00
Botond Dénes
60570d7114 Merge 'topology coordinator: restrict node join/remove to preserve RF-rack validity' from Michael Litvak
Allow creating materialized views and secondary indexes in a tablets keyspace only if it's RF-rack-valid, and enforce RF-rack-validity while the keyspace has views by restricting some operations:
* Altering a keyspace's RF if it would make the keyspace RF-rack-invalid
* Adding a node in a new rack
* Removing / Decommissioning the last node in a rack

Previously the config option `rf_rack_valid_keyspaces` was required for creating views. We now remove this restriction - it's not needed because we always maintain RF-rack-validity for keyspaces with views.

The restrictions are relevant only for keyspaces with numerical RF. Keyspace with rack-list-based RF are always RF-rack-valid.

Fixes scylladb/scylladb#23345
Fixes https://github.com/scylladb/scylladb/issues/26820

backport to relevant versions for materialized views with tablets since it depends on rf-rack validity

Closes scylladb/scylladb#26354

* github.com:scylladb/scylladb:
  docs: update RF-rack restrictions
  cql3: don't apply RF-rack restrictions on vector indexes
  cql3: add warning when creating mv/index with tablets about rf-rack
  service/tablet_allocator: always allow tablet merge of tables with views
  locator: extend rf-rack validation for rack lists
  test: test rf-rack validity when creating keyspace during node ops
  locator: fix rf-rack validation during node join/remove
  test: test topology restrictions for views with tablets
  test: add test_topology_ops_with_rf_rack_valid
  topology coordinator: restrict node join/remove to preserve RF-rack validity
  topology coordinator: add validation to node remove
  locator: extend rf-rack validation functions
  view: change validate_view_keyspace to allow MVs if RF=Racks
  db: enforce rf-rack-validity for keyspaces with views
  replica/db: add enforce_rf_rack_validity_for_keyspace helper
  db: remove enforce parameter from check_rf_rack_validity
  test: adjust test to not break rf-rack validity
2026-01-09 10:01:23 +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
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
Michael Litvak
75b5285cdf cql3: don't apply RF-rack restrictions on vector indexes
When creating an index we validate that the keyspace is RF-rack-valid
and print a warning that the keyspace must remain RF-rack-valid.

This should apply only to indexes that are based on materialized views
for which there are consistency concerns when the keyspace is not
RF-rack-valid.

vector indexes are not based on materialized views, hence these
restrictions should not apply to them.
2025-12-22 09:21:07 +01:00
Michael Litvak
06343b58a2 cql3: add warning when creating mv/index with tablets about rf-rack
Creating a MV or index in a tablets-based keyspace now forces additional
restrictions on the keyspace. The keyspace must be RF-rack-valid and it
must remain RF-rack-valid while the view exists.

Add a CQL warning about these restrictions.
2025-12-22 09:21:06 +01:00
Michael Litvak
9940dcefa7 test: test topology restrictions for views with tablets
Add tests that verify the restrictions on topology operations when there
are keyspaces with tablets and materialized views.

For such keyspaces, RF=Racks must be enforced while they have
materialized views, therefore adding a node in a new rack or removing a
node that would eliminate a rack should be rejected.
2025-12-22 09:14:30 +01:00
Michael Litvak
8df61f6d99 view: change validate_view_keyspace to allow MVs if RF=Racks
The function validate_view_keyspace checks if a keyspace is eligible for
having materialized views, and it is used for validation when creating a
MV or a MV-based index.

Previously, it was required that the rf_rack_valid_keyspaces option is
set in order for tablets-based keyspaces to be considered eligible, and
the RF-rack condition was enforced when the option is set.

Instead of this, we change the validation to allow MVs in a keyspace if
the RF-rack condition is satisfied for the keyspace - regardless of the
config option.

We remove the config validation for views on startup that validates the
option `rf_rack_valid_keyspaces` is set if there are any views with
tablets, since this is not required anymore.

We can do this without worrying about upgrades because this change will
be effective from 2025.4 where MVs with tablets are first out of
experimental phase.

We update the test for MV and index restrictions in tablets keyspaces
according to the new requirements.

* Create MV/index: previously the test checked that it's allowed only if
  the config option `rf_rack_valid_keyspaces` is set. This is changed
  now so it's always allowed to create MV/index if the keyspace is
  RF-rack-valid. Update the test to verify that we can create MV/index
  when the keyspace is RF-rack-valid, even if the rf_rack option is not
  set, and verify that it fails when the keyspace is RF-rack-invalid.
* Alter: Add a new test to verify that while a keyspace has views, it
  can't be altered to become RF-rack-invalid.
2025-12-22 09:14:29 +01:00
Dawid Mędrek
58dc414912 test/cluster/mv: Rewrite test_view_building_scheduling_group
We rewrite the test to avoid flakiness. Instead of looking at the
metrics, we make a trade-off and start depending on a less reliable
mechanism -- logs. We grep all relevant messages printed by Scylla
in TRACE mode and make sure that they were all printed from a context
using the streaming scheduling group.

Although it's a "less proper" way of testing, it should be much more
dependable and avoid flakiness.

Fixes scylladb/scylladb#25957

Closes scylladb/scylladb#26656
2025-12-08 14:24:25 +02:00
Aleksandra Martyniuk
76174d1f7a cql3: reject ALTER KEYSPACE if rf of datacenter with tablets is omitted
In ALTER KEYSPACE, when a datacenter name is omitted, its replication
factor is implicitly set to zero with vnodes, while with tablets,
it remains unchanged.

ALTER KEYSPACE should behave the same way for tablets as it does
for vnodes. However, this can be dangerous as we may mistakenly
drop the whole datacenter.

Reject ALTER KEYSPACE if it changes replication factor, but omits
a datacenter that currently contains tablet replicas.

Fixes: https://github.com/scylladb/scylladb/issues/25549.

Closes scylladb/scylladb#25731
2025-11-24 06:36:51 +02:00
Botond Dénes
2ca66133a4 Revert "db/config: don't use RBNO for scaling"
This reverts commit 43738298be.

This commit causes instability in dtests. Several non-gating dtests
started failing, as well as some gating ones, see #27047.

Closes scylladb/scylladb#27067

Fixes #27047
2025-11-18 08:17:17 +02:00
Piotr Dulikowski
2ccc94c496 Merge 'topology_coordinator: include joining node in barrier' from Michael Litvak
Previously, only nodes in the 'normal' state and decommissioning nodes
were included in the set of nodes participating in barrier and
barrier_and_drain commands. Joining nodes are not included because they
don't coordinate requests, given their cql port is closed.

However, joining nodes may receive mutations from other nodes, for which
they may generate and coordinate materialized view updates. If their
group0 state is not synchronized it could cause lost view updates.
For example:

1. On the topology coordinator, the join completes and the joining node
   becomes normal, but the joining node's state lags behind. Since it's
   not synchronized by the barrier, it could be in an old state such as
   `write_both_read_old`.
2. A normal node coordinates a write and sends it to the new node as the
   new replica.
3. The new node applies the base mutation but doesn't generate a view
   update for it, because it calculates the base-view pairing according
   to its own state and replication map, and determines that it doesn't
   participate in the base-view pairing.

Therefore, since the joining node participates as a coordinator for view
updates, it should be included in these barriers as well. This ensures
that before the join completes, the joining node's state is
`write_both_read_new`, where it does generate view updates.

Fixes https://github.com/scylladb/scylladb/issues/26976

backport to previous versions since it fixes a bug in MV with vnodes

Closes scylladb/scylladb#27008

* github.com:scylladb/scylladb:
  test: add mv write during node join test
  topology_coordinator: include joining node in barrier
2025-11-14 12:41:16 +01:00
Botond Dénes
43738298be db/config: don't use RBNO for scaling
Remove bootstrap and decomission from allowed_repair_based_node_ops.
Using RBNO over streaming for these operations has no benefits, as they
are not exposed to the out-of-date replica problem that replace,
removenode and rebuild are.
On top of that, RBNO is known to have problems with empty user tables.
Using streaming for boostrap and decomission is safe and faster
than RBNO in all condition, especially when the table is small.

One test needs adjustment as it relies on RBNO being used for all node
ops.

Fixes: #24664

Closes scylladb/scylladb#26330
2025-11-14 13:03:50 +03:00
Dawid Mędrek
393f1ca6e6 tet/cluster/mv: Clean up test_backoff_when_node_fails_task_rpc
After the changes in the test, we clean up its syntax. It boils
down to very simple modifications.
2025-11-13 17:57:33 +01:00
Dawid Mędrek
acd9120181 db/view/view_building_coordinator: Rate limit logging failed RPC
The view building coordinator sends tasks in form of RPC messages
to other nodes in the cluster. If processing that RPC fails, the
coordinator logs the error.

However, since tasks are per replica (so per shard), it may happen
that we end up with a large number of similar messages, e.g. if the
target node has died, because every shard will fail to process its
RPC message. It might become even worse in the case of a network
partition.

To mitigate that, we rate limit the logging by 1 seconds.

We extend the test `test_backoff_when_node_fails_task_rpc` so that
it allows the view building coordinator to have multiple tablet
replica targets. If not for rate limiting the warning messages,
we should start getting more of them, potentially leading to
a test failure.
2025-11-13 17:57:23 +01:00
Dawid Mędrek
4a5b1ab40a db/view: Add backoff when RPC fails
The view building coordinator manages the process of view building
by sending RPC requests to all nodes in the cluster, instructing them
what to do. If processing that message fails, the coordinator decides
if it wants to retry it or (temporarily) abandon the work.

An example of the latter scenario could be if one of the target nodes
dies and any attempts to communicate with it would fail.

Unfortunately, the current approach to it is not perfect and may result
in a storm of warnings, effectively clogging the logs. As an example,
take a look at scylladb/scylladb#26686: the gossiper failed to mark
one of the dead nodes as DOWN fast enough, and it resulted in a warning storm.

To prevent situations like that, we implement a form of backoff.
If processing an RPC message fails, we postpone finishing the task for
a second. That should reduce the number of messages in the logs and avoid
retries that are likely to fail as well.

We provide a reproducer test: it fails before this commit and succeeds
with it.

Fixes scylladb/scylladb#26686
2025-11-13 17:55:41 +01:00
Michael Litvak
b925e047be test: add mv write during node join test
Add a test that reproduces the issue scylladb/scylladb#26976.

The test adds a new node with delayed group0 apply, and does writes with
MV updates right after the join completes on the coordinator and while
the joining node's state is behind.

The test fails before fixing the issue and passes after.
2025-11-13 12:24:32 +01:00
Piotr Szymaniak
63897370cb alternator: Fix tag name to request vnodes
The tag was lately renamed from `experimental:initial_tablets` to
`system::initial_tablets`. This commit fixes both the tests as well as
the exceptions sent to the user instructing how to create table with
vnodes.
2025-11-09 12:52:29 +02:00
Wojciech Mitros
0a22ac3c9e mv: don't mark the view as built if the reader produced no partitions
When we build a materialized view we read the entire base table from start to
end to generate all required view udpates. If a view is created while another view
is being built on the same base table, this is optimized - we start generating
view udpates for the new view from the base table rows that we're currently
reading, and we read the missed initial range again after the previous view
finishes building.
The view building progress is only updated after generating view updates for
some read partitions. However, there are scenarios where we'll generate no
view updates for the entire read range. If this was not handled we could
end up in an infinite view building loop like we did in https://github.com/scylladb/scylladb/issues/17293
To handle this, we mark the view as built if the reader generated no partitions.
However, this is not always the correct conclusion. Another scenario where
the reader won't encounter any partitions is when view building is interrupted,
and then we perform a reshard. In this scenario, we set the reader for all
shards to the last unbuilt token for an existing partition before the reshard.
However, this partition may not exist on a shard after reshard, and if there
are also no partitions with higher tokens, the reader will generate no partitions
even though it hasn't finished view building.
Additionally, we already have a check that prevents infinite view building loops
without taking the partitions generated by the reader into account. At the end
of stream, before looping back to the start, we advance current_key to the end
of the built range and check for built views in that range. This handles the case
where the entire range is empty - the conditions for a built view are:
1. the "next_token" is no greater than "first_token" (the view building process
looped back, so we've built all tokens above "first_token")
2. the "current_token" is no less than "first_token" (after looping back, we've
built all tokens below "first_token")

If the range is empty, we'll pass these conditions on an empty range after advancing
"current_key" to the end because:
1. after looping back, "next_token" will be set to `dht::minimum_token`
2. "current_key" will be set to `dht::ring_position::max()`

In this patch we remove the check for partitions generated by the reader. This fixes
the issue with resharding and it does not resurrect the issue with infinite view building
that the check was introduced for.

Fixes https://github.com/scylladb/scylladb/issues/26523

Closes scylladb/scylladb#26635
2025-11-05 17:02:32 +02:00
Tomasz Grabiec
5bf7112fe6 test: cluster: mv: Do not move tablets across racks
It's illegal with rf-rack-valid keyspaces.
2025-10-29 23:32:57 +01:00
Piotr Dulikowski
a8d92f2abd test: mv: add a test for tablet merge
The test test_mv_tablets_replace verifies that merging tablets of both a
view and its base table is allowed if rf-rack-valid-keyspaces option is
enabled (and it is enabled by default in the test suite).
2025-10-16 14:07:37 +02:00
Dawid Mędrek
3aa07d7dfe test/cluster/mv: Provide reason why test is skipped
We point to the issue explaining why the test was disabled
and what can be done about it.

Closes scylladb/scylladb#26541
2025-10-15 09:22:39 +02:00
Piotr Dulikowski
e7907b173a Merge 'db/view: Require rf_rack_valid_keyspaces when creating materialized view' from Dawid Mędrek
Materialized views are currently in the experimental phase and using them
in tablet-based keyspaces requires starting Scylla with an experimental feature,
`views-with-tablets`. Any attempts to create a materialized view or secondary
index when it's not enabled will fail with an appropriate error.

After considerable effort, we're drawing close to bringing views out of the
experimental phase, and the experimental feature will no longer be needed.
However, materialized views in tablet-based keyspaces will still be restricted,
and creating them will only be possible after enabling the configuration option
`rf_rack_valid_keyspaces`. That's what we do in this PR.

In this patch, we adjust existing tests in the tree to work with the new
restriction. That shouldn't have been necessary because we've already seemingly
adjusted all of them to work with the configuration option, but some tests hid
well. We fix that mistake now.

After that, we introduce the new restriction. What's more, when starting Scylla,
we verify that there is no materialized view that would violate the contract.
If there are some that do, we list them, notify the user, and refuse to start.

High-level implementation strategy:

1. Name the restrictions in form of a function.
2. Adjust existing tests.
3. Restrict materialized views by both the experimental feature
   and the configuration option. Add validation test.
4. Drop the requirement for the experimental feature. Adjust the added test
   and add a new one.
5. Update the user documentation.

Fixes scylladb/scylladb#23030

Backport: 2025.4, as we are aiming to support materialized views for tablets from that version.

Closes scylladb/scylladb#25802

* github.com:scylladb/scylladb:
  view: Stop requiring experimental feature
  db/view: Verify valid configuration for tablet-based views
  db/view: Require rf_rack_valid_keyspaces when creating view
  test/cluster/random_failures: Skip creating secondary indexes
  test/cluster/mv: Mark test_mv_rf_change as skipped
  test/cluster: Adjust MV tests to RF-rack-validity
  test/boost/schema_loader_test.cc: Explicitly enable rf_rack_valid_keyspaces
  db/view: Name requirement for views with tablets
2025-10-06 12:46:46 +02:00
Dawid Mędrek
b409e85c20 view: Stop requiring experimental feature
We modify the requirements for using materialized views in tablet-based
keyspaces. Before, it was necessary to enable the configuration option
`rf_rack_valid_keyspaces`, having the cluster feature `VIEWS_WITH_TABLETS`
enabled, and using the experimental feature `views-with-tablets`.
We drop the last requirement.

We adjust code to that change and provide a new validation test.
We also update the user documentation to reflect the changes.

Fixes scylladb/scylladb#23030
2025-10-01 09:01:53 +02:00
Dawid Mędrek
00222070cd db/view: Require rf_rack_valid_keyspaces when creating view
We extend the requirements for being able to create materialized views
and secondary indexes in tablet-based keyspaces. It's now necessary to
enable the configuration option `rf_rack_valid_keyspaces`. This is
a stepping stone towards bringing materialized views and secondary
indexes with tablets out of the experimental phase.

We add a validation test to verify the changes.

Refs scylladb/scylladb#23030
2025-10-01 09:01:50 +02:00
Dawid Mędrek
6322b5996d test/cluster/mv: Mark test_mv_rf_change as skipped
The test will not work with `rf_rack_valid_keyspaces`. Since the option
is going to become a requirement for using views with tablets, the test
will need to be rewritten to take that into consideration. Since that
adjustment doesn't seem trivial, we mark the test as skipped for the
time being.
2025-10-01 09:01:29 +02:00
Dawid Mędrek
994f09530f test/cluster: Adjust MV tests to RF-rack-validity
Some of the new tests covering materialized views explicitly disabled
the configuration option `rf_rack_valid_keyspaces`. It's going to become
a new requirement for views with tablets, so we adjust those tests and
enable the option. There is one exception, the test:

`cluster/mv/test_mv_topology_change.py::test_mv_rf_change`

We handle it separately in the following commit.
2025-09-30 20:01:25 +02:00
Michael Litvak
d94c1f6674 test: mv: test view update during topology operations
add new test cases checking view consistency when writing to a table
with MV and generating view updates while data is migrated.

one case has tablet migrations while writing to the table. The other
case does the equivalent for vnode keyspaces - it adds a new node.

The tests reproduce issue scylladb/scylladb#24292
2025-09-29 13:44:04 +02:00
Wojciech Mitros
d9b8278178 mv: handle mismatched base/view replica count caused by RF change
During an ALTER KEYSPACE statement execution where a table with a view
is present, we need to perform tablet migrations for both tables.
These migrations are not synchronized, so at some point the base may
have a different number of non-pending replicas than the view. Because
of that, we can't pair them correctly. If there is more non-pending
base replicas than view replicas, we don't need to do anything because
the view replica that didn't finish migrating is a pending replica
and will get view updates from all base replicas. But if there is more
non-pending view replicas than base replicas, we may currently lose
view updates to the new view replica.

This patch adds a workaround for this scenario. If after one migration
we have too more non-pending view replicas than base replicas, we add
it to the pending replica list so that it gets an update anyway.

This patch will also take effect if the base and view replica counts
differ due to some other bug. To track that, a new metric is added
to count such occurrences.

This patch also includes a test for this exact scenario, which is enforced by an injection.

Fixes https://github.com/scylladb/scylladb/issues/21492
2025-09-22 12:50:16 +02:00
Michael Litvak
3dffb8e0dc test: mv: add a test for view build interrupt during registration
Add a new test that reproduces issue #22989. The test starts view
building and interrupts it by restarting the node while some shards
registered their status and some didn't.
2025-09-21 10:39:30 +02:00
Wojciech Mitros
f17beba834 load_balancer: include dead nodes when calculating rack load
Load balancer aims to preserve a balance in rack loads when generating
tablet migrations. However, this balance might get broken when dead nodes
are present. Currently, these nodes aren't include in rack load calculations,
even if they own tablet replicas. As a result, load balancer treats racks
with dead nodes as racks with a lower load, so I generates migrations to these
racks.
This is incorrect, because a dead node might come back alive, which would result
in having multiple tablet replicas on the same rack. It's also inefficient
even if we know that the node won't come back - when it's being replaced or removed.
In that case we know we are going to rebuild the lost tablet replicas
so migrating tablets to this rack just doubles the work. Allowing such migrations
to happen would also require adjustments in the materialized view pairing code
because we'd temporarily allow having multiple tablet replicas on the same rack.
So in this patch we include dead nodes when calculating rack loads in the load
balancer. The dead nodes still aren't treated as potential migration sources or
destinations.
We also add a test which verifies that no migrations are performed by doing a node
replace with a mv workload in parallel. Before the patch, we'd get pairing errors
and after the patch, no pairing errors are detected.

Fixes https://github.com/scylladb/scylladb/issues/24485

Closes scylladb/scylladb#26028
2025-09-17 20:49:18 +02:00
Michał Jadwiszczak
cf138da853 test: adjust existing tests
- Disable tablets in `test_migration_on_existing_raft_topology`.
Because views on tablets are experimental now, we can safely
assume that view building coordinator will start with view build status
on raft.
- Add error injection to pause view building on worker.
Used to pause view building process, there is analogous error injection
in view_builder.
- Do a read barrier in `test_view_in_system_tables`
Increases test stability by making sure that the node sees up-to-date
group0 state and `system.built_views` is synced.
- Wait for view is build in some tests
Increases tests stability by making sure that the view is built.
- Remove xfail marker from `test_tablet_streaming_with_unbuilt_view`
This series fix https://github.com/scylladb/scylladb/issues/21564
and this test should work now.
2025-08-27 10:23:04 +02:00