Package org.apache.druid.server.compaction

Class MostFragmentedIntervalFirstPolicy

java.lang.Object

org.apache.druid.server.compaction.BaseCandidateSearchPolicy

org.apache.druid.server.compaction.MostFragmentedIntervalFirstPolicy

All Implemented Interfaces:

CompactionCandidateSearchPolicy

public class MostFragmentedIntervalFirstPolicy
extends BaseCandidateSearchPolicy

Experimental CompactionCandidateSearchPolicy which prioritizes compaction of intervals with the largest number of small uncompacted segments.

This policy favors cluster stability (by prioritizing reduction of segment count) over performance of queries on newer intervals. For the latter, use NewestSegmentFirstPolicy.

Constructor Summary

Constructors

Constructor	Description
MostFragmentedIntervalFirstPolicy(Integer minUncompactedCount, HumanReadableBytes minUncompactedBytes, HumanReadableBytes maxAverageUncompactedBytesPerSegment, Integer minUncompactedBytesPercentForFullCompaction, Integer minUncompactedRowsPercentForFullCompaction, String priorityDatasource)

Method Summary

Modifier and Type	Method	Description
Eligibility	checkEligibilityForCompaction(CompactionCandidate candidate, CompactionTaskStatus latestTaskStatus)	Checks if the given CompactionCandidate is eligible for compaction in the current iteration.
boolean	equals(Object o)
HumanReadableBytes	getMaxAverageUncompactedBytesPerSegment()	Maximum average size of uncompacted segments in an interval eligible for compaction.
HumanReadableBytes	getMinUncompactedBytes()	Minimum total bytes of uncompacted segments that must be present in an interval to make it eligible for compaction.
int	getMinUncompactedCount()	Minimum number of uncompacted segments that must be present in an interval to make it eligible for compaction.
protected Comparator<CompactionCandidate>	getSegmentComparator()	Compares between two compaction candidates.
int	hashCode()
int	minUncompactedBytesPercentForFullCompaction()	Threshold percentage of uncompacted bytes to total bytes below which minor compaction is eligible instead of full compaction.
int	minUncompactedRowsPercentForFullCompaction()	Threshold percentage of uncompacted rows to total rows below which minor compaction is eligible instead of full compaction.
String	toString()

Methods inherited from class org.apache.druid.server.compaction.BaseCandidateSearchPolicy

compareCandidates, getPriorityDatasource

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

MostFragmentedIntervalFirstPolicy

public MostFragmentedIntervalFirstPolicy(@Nullable
 Integer minUncompactedCount,
 @Nullable
 HumanReadableBytes minUncompactedBytes,
 @Nullable
 HumanReadableBytes maxAverageUncompactedBytesPerSegment,
 @Nullable
 Integer minUncompactedBytesPercentForFullCompaction,
 @Nullable
 Integer minUncompactedRowsPercentForFullCompaction,
 @Nullable
 String priorityDatasource)

Method Details

getMinUncompactedCount

public int getMinUncompactedCount()

Minimum number of uncompacted segments that must be present in an interval to make it eligible for compaction.

getMinUncompactedBytes

public HumanReadableBytes getMinUncompactedBytes()

Minimum total bytes of uncompacted segments that must be present in an interval to make it eligible for compaction. Default value is SIZE_10_MB.

getMaxAverageUncompactedBytesPerSegment

public HumanReadableBytes getMaxAverageUncompactedBytesPerSegment()

Maximum average size of uncompacted segments in an interval eligible for compaction. Default value is SIZE_2_GB.

minUncompactedBytesPercentForFullCompaction

public int minUncompactedBytesPercentForFullCompaction()

Threshold percentage of uncompacted bytes to total bytes below which minor compaction is eligible instead of full compaction. Default value is 0.

minUncompactedRowsPercentForFullCompaction

public int minUncompactedRowsPercentForFullCompaction()

Threshold percentage of uncompacted rows to total rows below which minor compaction is eligible instead of full compaction. Default value is 0.

getSegmentComparator

protected Comparator<CompactionCandidate> getSegmentComparator()

Description copied from class: BaseCandidateSearchPolicy

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

Specified by:

getSegmentComparator in class BaseCandidateSearchPolicy

equals

public boolean equals(Object o)

Overrides:

equals in class BaseCandidateSearchPolicy

hashCode

public int hashCode()

Overrides:

hashCode in class BaseCandidateSearchPolicy

toString

public String toString()

Overrides:

toString in class Object

checkEligibilityForCompaction

public Eligibility checkEligibilityForCompaction(CompactionCandidate candidate,
 CompactionTaskStatus latestTaskStatus)

Description copied from interface: CompactionCandidateSearchPolicy

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.

Specified by:

checkEligibilityForCompaction in interface CompactionCandidateSearchPolicy

Overrides:

checkEligibilityForCompaction in class BaseCandidateSearchPolicy

Returns:

Eligibility.FULL only if eligible.