[FLINK-15637] For RocksDBStateBackend, make RocksDB the default store for timers

• Type: Improvement
• Status: Closed
• Priority: Blocker
• Resolution: Done
• Fix Version/s: 1.10.0
• Component/s: Runtime / State Backends
• Labels: pull-request-available

Release Note

After FLINK-15637, we change the default timer store from heap to RocksDB for RocksDBStateBackend to support asynchronous snapshots for timer state and better scalability, with less than 5% performance cost. If you find the performance decline critical, please set "state.backend.rocksdb.timer-service.factory" to "HEAP" in flink-conf.yaml to restore the old behavior.

• Assignee: Congxian Qiu
• Reporter: Stephan Ewen
• Created: 17/Jan/20 13:31
• Updated: 21/Jan/20 08:49
• Resolved: 21/Jan/20 08:49

Description

Set the state.backend.rocksdb.timer-service.factory to ROCKSDB by default. Also ensure that the programmatic default value becomes the same.

We need to update the performance tuning guide to mention this.
 
We need to update the release notes to mention this.

This is a decision concluded from ML discussion (as well as a twitter vote).

 

Issue Links

• links to: GitHub Pull Request #10893