Most likely 817fdad uncovered the fact that our choice of primary replica was resonating with tablet allocation and we were ending up picking the same replica as primary within a scope instead of rotating primaryship among all replicas in the scope.
This created situations where for instance, restoring into a 9 nodes with primary_replica_only=true would put all data into 3 nodes, leaving the other 6 unused. The balancing of the dataset was performed by the subsequent repair step.
This PR fixes this by changing the formula for picking up the primary replica out of a set of eligible replicas from within the passed scope.
The PR also extends the testing scenarios in `test_backup.py` so we get to run restore for a set of topologies, for all combinations of scope, primary_replica_only and min_tablet_counts.
Most of the work was done by @bhalevy [here](https://github.com/scylladb/scylladb/compare/master...bhalevy:scylla:load-balance-primary-replica), this PR just splitted it and did touchups here and there.
Fixes #27281
Closes scylladb/scylladb#27397
* github.com:scylladb/scylladb:
test: reduce dataset and number of test cases or debug builds
test: bump repair timeout up, it's sometimes not enough in CI
test: refactor test_refresh.py to match test_restore_with_streaming_scopes.
test: extend test_restore_with_streaming_scopes
test: Adjust test_restore_primary_replica_different_dc_scope_all
test: Refactor restoring code in test_backup to match SM pattern
test: add check_mutation_replicas calls after fresh creation of dataset
test: extend create_dataset to accept consistency_level
test: refactor check_mutation_replicas so it's more readable
test: make create_dataset async and refactor so it's configurable
test: use defaultdict in collect_mutations
test: add log marks to facilitate reusing server for restore
locator: tablets: Distribute data evenly among primary replicas during restore
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.