[RATIS-2142] OOM for stateMachineCache use cases

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 3.1.0
• Component/s: server
• Target Version/s: 3.1.1
• Assignee: Unassigned
• Reporter: Duong
• Created: 21/Aug/24 01:03
• Updated: 21/Aug/24 16:58
• Resolved: 21/Aug/24 16:58

Description

In 3.1.0, with stateMachineCache enabled, the RaftLogCache entries contain a reference to the original RaftClientRequest. This is not supposed to happen as RaftLogCache entries should only refer to the LogEntries with data truncated. 

This problem impacts Apache Ozone. The reference form RaftLogCache entries prevent the original RaftClientRequest (which contains a large data chunk) to be GCed timely. The result is Ozone datanodes quickly run out of heap memory.

This is not the case with the latest master branch, only with the 3.1.0 release.

Issue Links

• duplicates: RATIS-2141 OOM for stateMachineCache use cases