org.apache.ratis.server.raftlog.segmented

Interface CacheInvalidationPolicy

All Known Implementing Classes:

CacheInvalidationPolicy.CacheInvalidationPolicyDefault

public interface CacheInvalidationPolicy

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	CacheInvalidationPolicy.CacheInvalidationPolicyDefault

Method Summary

Modifier and Type	Method and Description
List<LogSegment>	evict(long[] followerNextIndices, long safeEvictIndex, long lastAppliedIndex, org.apache.ratis.server.raftlog.segmented.SegmentedRaftLogCache.LogSegmentList segments, int maxCachedSegments) Determine which log segments should evict their log entry cache

Method Detail

evict

List<LogSegment> evict(long[] followerNextIndices,
                       long safeEvictIndex,
                       long lastAppliedIndex,
                       org.apache.ratis.server.raftlog.segmented.SegmentedRaftLogCache.LogSegmentList segments,
                       int maxCachedSegments)

Determine which log segments should evict their log entry cache

Parameters:

followerNextIndices - the next indices of all the follower peers. Null if the local peer is not a leader.

safeEvictIndex - the index up to which cache can be evicted. This index depends on two factors: 1. the largest index belonging to a closed segment 2. the latest snapshotIndex Logs with endIndex less than the max of these two indices can be evicted.

lastAppliedIndex - the last index that has been applied to state machine

segments - The list of log segments. The segments should be sorted in ascending order according to log index.

maxCachedSegments - the max number of segments with cached log entries

Returns:

the log segments that should evict cache