[FLINK-8715] RocksDB does not propagate reconfiguration of serializer to the states

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 1.3.2
• Fix Version/s: 1.5.0
• Component/s: Runtime / State Backends
• Assignee: Tzu-Li (Gordon) Tai
• Reporter: Arvid Heise
• Created: 20/Feb/18 12:16
• Updated: 22/Jun/21 14:07
• Resolved: 28/Apr/18 09:09

Description

Any changes to the serializer done in #ensureCompability are lost during the state creation.

In particular, https://github.com/apache/flink/blob/master/flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBValueState.java#L68 always uses a fresh copy of the StateDescriptor.

An easy fix is to pass the reconfigured serializer as an additional parameter in https://github.com/apache/flink/blob/master/flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/RocksDBKeyedStateBackend.java#L1681 , which can be retrieved through the side-output of getColumnFamily

kvStateInformation.get(stateDesc.getName()).f1.getStateSerializer()

I encountered it in 1.3.2 but the code in the master seems unchanged (hence the pointer into master). I encountered it in ValueState, but I suspect the same issue can be observed for all kinds of RocksDB states.

Issue Links

• links to: GitHub Pull Request #5885