Class MergeOnFlushMergePolicy
- All Implemented Interfaces:
Unwrappable<MergePolicy>
MergePolicy
to merge all tiny segments (or at least segments
smaller than specified in setSmallSegmentThresholdMB(double)
into one segment on commit.-
Nested Class Summary
Nested ClassesModifier and TypeClassDescription(package private) static class
Utility class to handle conversion between megabytes and bytesNested classes/interfaces inherited from class org.apache.lucene.index.MergePolicy
MergePolicy.MergeAbortedException, MergePolicy.MergeContext, MergePolicy.MergeException, MergePolicy.MergeSpecification, MergePolicy.OneMerge, MergePolicy.OneMergeProgress
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Field Summary
FieldsFields inherited from class org.apache.lucene.index.FilterMergePolicy
in
Fields inherited from class org.apache.lucene.index.MergePolicy
DEFAULT_MAX_CFS_SEGMENT_SIZE, DEFAULT_NO_CFS_RATIO, maxCFSSegmentSize, noCFSRatio
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Constructor Summary
ConstructorsConstructorDescriptionMergeOnFlushMergePolicy
(MergePolicy mergePolicy) Creates a MergeOnFlushMergePolicy merge policy instance wrapping another. -
Method Summary
Modifier and TypeMethodDescriptionfindFullFlushMerges
(MergeTrigger mergeTrigger, SegmentInfos segmentInfos, MergePolicy.MergeContext mergeContext) Identifies merges that we want to execute (synchronously) on commit.double
void
setSmallSegmentThresholdMB
(double smallSegmentThresholdMB) Methods inherited from class org.apache.lucene.index.FilterMergePolicy
findForcedDeletesMerges, findForcedMerges, findMerges, findMerges, getMaxCFSSegmentSizeMB, getNoCFSRatio, keepFullyDeletedSegment, maxFullFlushMergeSize, numDeletesToMerge, setMaxCFSSegmentSizeMB, setNoCFSRatio, size, toString, unwrap, useCompoundFile
Methods inherited from class org.apache.lucene.index.MergePolicy
assertDelCount, isMerged, message, segString, verbose
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Field Details
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smallSegmentThresholdBytes
private long smallSegmentThresholdBytes
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Constructor Details
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MergeOnFlushMergePolicy
Creates a MergeOnFlushMergePolicy merge policy instance wrapping another.- Parameters:
mergePolicy
- the wrappedMergePolicy
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Method Details
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getSmallSegmentThresholdMB
public double getSmallSegmentThresholdMB() -
setSmallSegmentThresholdMB
public void setSmallSegmentThresholdMB(double smallSegmentThresholdMB) - Parameters:
smallSegmentThresholdMB
- all segments smaller than this will be merged into a single segment before commit completes.
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findFullFlushMerges
public MergePolicy.MergeSpecification findFullFlushMerges(MergeTrigger mergeTrigger, SegmentInfos segmentInfos, MergePolicy.MergeContext mergeContext) throws IOException Description copied from class:MergePolicy
Identifies merges that we want to execute (synchronously) on commit. By default, this will returnnatural merges
whose segments are all less than themax segment size for full flushes
.Any merges returned here will make
IndexWriter.commit()
,IndexWriter.prepareCommit()
orIndexWriter.getReader(boolean, boolean)
block until the merges complete or untilLiveIndexWriterConfig.getMaxFullFlushMergeWaitMillis()
has elapsed. This may be used to merge small segments that have just been flushed, reducing the number of segments in the point in time snapshot. If a merge does not complete in the allotted time, it will continue to execute, and eventually finish and apply to future point in time snapshot, but will not be reflected in the current one.If a
MergePolicy.OneMerge
in the returnedMergePolicy.MergeSpecification
includes a segment already included in a registered merge, thenIndexWriter.commit()
orIndexWriter.prepareCommit()
will throw aIllegalStateException
. UseMergePolicy.MergeContext.getMergingSegments()
to determine which segments are currently registered to merge.- Overrides:
findFullFlushMerges
in classFilterMergePolicy
- Parameters:
mergeTrigger
- the event that triggered the merge (COMMIT or GET_READER).segmentInfos
- the total set of segments in the index (while preparing the commit)mergeContext
- the MergeContext to find the merges on, which should be used to determine which segments are already in a registered merge (seeMergePolicy.MergeContext.getMergingSegments()
).- Throws:
IOException
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