bf18a17bd6
When tablet scheduler drains nodes, it chooses target location based on "badness" metric. Nodes with lowest score are preferred. Before the patch, the score which was used was the number of tablets on that node post-movement. This way we populate least-loaded node first. But this works only if nodes have equal number of shards. If nodes have different capacity, then number of tablets is not a good metric, because we don't aim to equalize per-node count, but per-shard count. We assume that each shard has equal capacity. Because of this bug, during decommission, the nodes with fewer shards would be preferred to receive replicas, which may lead to overloading of those nodes. This imbalance would be later fixed by the normal load balancing logic, but it's still problematic. Fixes #21783 Closes scylladb/scylladb#21860
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.