Package org.apache.druid.server.compaction

Interface CompactionCandidateSearchPolicy

All Known Implementing Classes:

BaseCandidateSearchPolicy, FixedIntervalOrderPolicy, NewestSegmentFirstPolicy

public interface CompactionCandidateSearchPolicy

Policy used by CompactSegments duty to pick segments for compaction.

Method Summary

Modifier and Type	Method	Description
int	compareCandidates(CompactionCandidate candidateA, CompactionCandidate candidateB)	Compares between two compaction candidates.
boolean	isEligibleForCompaction(CompactionCandidate candidate, CompactionStatus currentCompactionStatus, CompactionTaskStatus latestTaskStatus)	Checks if the given CompactionCandidate is eligible for compaction in the current iteration.

Method Details

compareCandidates

int compareCandidates(CompactionCandidate candidateA,
 CompactionCandidate candidateB)

Compares between two compaction candidates. Used to determine the order in which segments and intervals should be picked for compaction.

Returns:

A positive value if candidateA should be picked first, a negative value if candidateB should be picked first or zero if the order does not matter.

isEligibleForCompaction

boolean isEligibleForCompaction(CompactionCandidate candidate,
 CompactionStatus currentCompactionStatus,
 CompactionTaskStatus latestTaskStatus)

Checks if the given CompactionCandidate is eligible for compaction in the current iteration. A policy may implement this method to skip compacting intervals or segments that do not fulfil some required criteria.