1998733228
On short-pages, cut short because of a tombstone prefix.
When page-results are filtered and the filter drops some rows, the
last-position is taken from the page visitor, which does the filtering.
This means that last partition and row position will be that of the last
row the filter saw. This will not match the last position of the
replica, when the replica cut the page due to tombstones.
When fetching the next page, this means that all the tombstone suffix of
the last page, will be re-fetched. Worse still: the last position of the
next page will not match that of the saved reader left on the replica, so
the saved reader will be dropped and a new one created from scratch.
This wasted work will show up as elevated tail latencies.
Fix by always taking the last position from raw query results.
Fixes: #22620
Closes scylladb/scylladb#22622
(cherry picked from commit 7ce932ce01)
Closes scylladb/scylladb#22719
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.