Files
scylladb/test
Ferenc Szili 56c65d08f6 test: fix flakyness caused by TRUNCATE retries
The test test_truncate_during_topology_change tests TRUNCATE TABLE while
bootstrapping a new node. With tablets enabled TRUNCATE is a global
topology operation which needs to serialize with boostrap.

When TRUNCATE TABLE is issued, it first checks if there is an already
queued truncate for the same table. This can happen if a previous
TRUNCATE operation has timed out, and the client retried. The newly
issued truncate will only join the queued one if it is waiting to be
processed, and will fail immediatelly if the TRUNCATE is already being
processed.

In this test, TRUNCATE will be retried after a timeout (1 minute) due to
the default retry policy, and will be retried up to 3 times, while the
bootstrap is delayed by 2 minutes. This means that the test can validate
the result of a truncate which was started after bootstrap was
completed.

Because of the way truncate joins existing truncate operations, we can
also have the following scenario:
- TRUNCATE times out after one minute because the new node is being
  bootstrapped
- the client retries the TRUNCATE command which also times out after 1m
- the third attempt is received during TRUNCATE being processed which
  fails the test

This patch changes the retry policy of the TRUNCATE operation to
FallthroughRetryPolicy which guarantees that TRUNCATE will not be
retried on timeout. It also increases the timeout of the TRUNCATE from 1
to 4 minutes. This way the test will actually validate the performance
of the TRUNCATE operation which was issued during bootstrap, instead of
the subsequent, retried TRUNCATEs which could have been issued after the
bootstrap was complete.

Fixes: #26347

Closes scylladb/scylladb#27245

(cherry picked from commit d883ff2317)

Closes scylladb/scylladb#27506
2025-12-23 17:07:33 +02:00
..

Scylla in-source tests.

For details on how to run the tests, see docs/dev/testing.md

Shared C++ utils, libraries are in lib/, for Python - pylib/

alternator - Python tests which connect to a single server and use the DynamoDB API unit, boost, raft - unit tests in C++ cqlpy - Python tests which connect to a single server and use CQL topology* - tests that set up clusters and add/remove nodes cql - approval tests that use CQL and pre-recorded output rest_api - tests for Scylla REST API Port 9000 scylla-gdb - tests for scylla-gdb.py helper script nodetool - tests for C++ implementation of nodetool

If you can use an existing folder, consider adding your test to it. New folders should be used for new large categories/subsystems, or when the test environment is significantly different from some existing suite, e.g. you plan to start scylladb with different configuration, and you intend to add many tests and would like them to reuse an existing Scylla cluster (clusters can be reused for tests within the same folder).

To add a new folder, create a new directory, and then copy & edit its suite.ini.