duongkame commented on PR #990: URL: https://github.com/apache/ratis/pull/990#issuecomment-1867157686
> This is not necessarily true -- when the log can be fast but the `StateMachine` is slow, `evictCache` can happen before `processClientRequest`. That's the reason why we need to keep the buffer sorted by log index, so if some entry is missed because `evictCache` happens before `processClientRequest`, it'll be caught by the next `evictCache`. All buffers ready to release can be easily addressed from a log index. This approach is way cleaner than managing each buffer separately. Also, `evictCache` only happens when [the cache capacity is about to be filled](https://github.com/apache/ratis/blob/master/ratis-server/src/main/java/org/apache/ratis/server/raftlog/segmented/SegmentedRaftLogCache.java#L445-L454). There may be (very) few occurences of `evictCache` before `processClientRequest` returns, but not the majority. Plus, as discussed as per RATIS-1979, in the case of stateMachineCachingEnabled, we may consider releasing zero-copy buffers much earlier than cache evict. The ability to release all zero copy buffers up to a certain log index seems to be crucial. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
