gaborgsomogyi opened a new pull request, #26134: URL: https://github.com/apache/flink/pull/26134
## What is the purpose of the change State processor API with RocksDB is extremely slow because it does the following for key deduplication: * Get keys from `columnFamility1` * Get keys from `columnFamility2` * Iterate over the keys * Calls `KeyedStateReaderFunction.readKey` * Removes the key from both column families Since key removal is slow compared to other operations the overall performance is unacceptable. Instead of the mentioned method we've migrated to the following: * Get keys from `columnFamility1` * Get keys from `columnFamility2` * Added `RocksMultiStateKeysIterator` which iterates on all column families at the same time in an ordered way As a result key deduplication happens on iteration time in a streaming manner. Important note that this change effects only state processor API, existing checkpointing save/restore code paths are untouched. ## Brief change log Changed state processor API key iteration deduplication algorithm. ## Verifying this change Existing unit tests + performance/correctness tests. ## Does this pull request potentially affect one of the following parts: - Dependencies (does it add or upgrade a dependency): no - The public API, i.e., is any changed class annotated with `@Public(Evolving)`: no - The serializers: no - The runtime per-record code paths (performance sensitive): yes - Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: no - The S3 file system connector: no ## Documentation - Does this pull request introduce a new feature? no - If yes, how is the feature documented? not applicable -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org