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Public Member Functions | Static Public Member Functions | Static Public Attributes | Protected Member Functions
Lucene::LogByteSizeMergePolicy Class Reference

This is a LogMergePolicy that measures size of a segment as the total byte size of the segment's files. More...

#include <LogByteSizeMergePolicy.h>

+ Inheritance diagram for Lucene::LogByteSizeMergePolicy:

Public Member Functions

 LogByteSizeMergePolicy (const IndexWriterPtr &writer)
 
virtual ~LogByteSizeMergePolicy ()
 
virtual String getClassName ()
 
boost::shared_ptr< LogByteSizeMergePolicyshared_from_this ()
 
void setMaxMergeMB (double mb)
 Determines the largest segment (measured by total byte size of the segment's files, in MB) that may be merged with other segments. Small values (eg., less than 50 MB) are best for interactive indexing, as this limits the length of pauses while indexing to a few seconds. Larger values are best for batched indexing and speedier searches.
 
double getMaxMergeMB ()
 Returns the largest segment (measured by total byte size of the segment's files, in MB) that may be merged with other segments.
 
void setMinMergeMB (double mb)
 Sets the minimum size for the lowest level segments. Any segments below this size are considered to be on the same level (even if they vary drastically in size) and will be merged whenever there are mergeFactor of them. This effectively truncates the "long tail" of small segments that would otherwise be created into a single level. If you set this too large, it could greatly increase the merging cost during indexing (if you flush many small segments).
 
double getMinMergeMB ()
 Get the minimum size for a segment to remain un-merged.
 
- Public Member Functions inherited from Lucene::LogMergePolicy
 LogMergePolicy (const IndexWriterPtr &writer)
 
virtual ~LogMergePolicy ()
 
boost::shared_ptr< LogMergePolicyshared_from_this ()
 
double getNoCFSRatio ()
 
void setNoCFSRatio (double noCFSRatio)
 If a merged segment will be more than this percentage of the total size of the index, leave the segment as non-compound file even if compound file is enabled. Set to 1.0 to always use CFS regardless of merge size.
 
int32_t getMergeFactor ()
 Returns the number of segments that are merged at once and also controls the total number of segments allowed to accumulate in the index.
 
void setMergeFactor (int32_t mergeFactor)
 Determines how often segment indices are merged by addDocument(). With smaller values, less RAM is used while indexing, and searches on unoptimized indices are faster, but indexing speed is slower. With larger values, more RAM is used during indexing, and while searches on unoptimized indices are slower, indexing is faster. Thus larger values (> 10) are best for batch index creation, and smaller values (< 10) for indices that are interactively maintained.
 
virtual bool useCompoundFile (const SegmentInfosPtr &segments, const SegmentInfoPtr &newSegment)
 Returns true if a newly flushed (not from merge) segment should use the compound file format.
 
void setUseCompoundFile (bool useCompoundFile)
 Sets whether compound file format should be used for newly flushed and newly merged segments.
 
bool getUseCompoundFile ()
 Returns true if newly flushed and newly merge segments are written in compound file format.
 
virtual bool useCompoundDocStore (const SegmentInfosPtr &segments)
 Returns true if the doc store files should use the compound file format.
 
void setUseCompoundDocStore (bool useCompoundDocStore)
 Sets whether compound file format should be used for newly flushed and newly merged doc store segment files (term vectors and stored fields).
 
bool getUseCompoundDocStore ()
 Returns true if newly flushed and newly merge doc store segment files (term vectors and stored fields) are written in compound file format.
 
void setCalibrateSizeByDeletes (bool calibrateSizeByDeletes)
 Sets whether the segment size should be calibrated by the number of deletes when choosing segments for merge.
 
bool getCalibrateSizeByDeletes ()
 Returns true if the segment size should be calibrated by the number of deletes when choosing segments for merge.
 
virtual void close ()
 Release all resources for the policy.
 
virtual MergeSpecificationPtr findMergesForOptimize (const SegmentInfosPtr &segmentInfos, int32_t maxSegmentCount, SetSegmentInfo segmentsToOptimize)
 Returns the merges necessary to optimize the index. This merge policy defines "optimized" to mean only one segment in the index, where that segment has no deletions pending nor separate norms, and it is in compound file format if the current useCompoundFile setting is true. This method returns multiple merges (mergeFactor at a time) so the MergeScheduler in use may make use of concurrency.
 
virtual MergeSpecificationPtr findMergesToExpungeDeletes (const SegmentInfosPtr &segmentInfos)
 Finds merges necessary to expunge all deletes from the index. We simply merge adjacent segments that have deletes, up to mergeFactor at a time.
 
virtual MergeSpecificationPtr findMerges (const SegmentInfosPtr &segmentInfos)
 Checks if any merges are now necessary and returns a MergePolicy.MergeSpecification if so. A merge is necessary when there are more than setMergeFactor segments at a given level. When multiple levels have too many segments, this method will return multiple merges, allowing the MergeScheduler to use concurrency.
 
void setMaxMergeDocs (int32_t maxMergeDocs)
 Determines the largest segment (measured by document count) that may be merged with other segments. Small values (eg., less than 10,000) are best for interactive indexing, as this limits the length of pauses while indexing to a few seconds. Larger values are best for batched indexing and speedier searches.
 
int32_t getMaxMergeDocs ()
 Returns the largest segment (measured by document count) that may be merged with other segments.
 
- Public Member Functions inherited from Lucene::MergePolicy
 MergePolicy (const IndexWriterPtr &writer)
 
virtual ~MergePolicy ()
 
boost::shared_ptr< MergePolicyshared_from_this ()
 
- Public Member Functions inherited from Lucene::LuceneObject
virtual ~LuceneObject ()
 
virtual void initialize ()
 Called directly after instantiation to create objects that depend on this object being fully constructed.
 
virtual LuceneObjectPtr clone (const LuceneObjectPtr &other=LuceneObjectPtr())
 Return clone of this object.
 
virtual int32_t hashCode ()
 Return hash code for this object.
 
virtual bool equals (const LuceneObjectPtr &other)
 Return whether two objects are equal.
 
virtual int32_t compareTo (const LuceneObjectPtr &other)
 Compare two objects.
 
virtual String toString ()
 Returns a string representation of the object.
 
- Public Member Functions inherited from Lucene::LuceneSync
virtual ~LuceneSync ()
 
virtual SynchronizePtr getSync ()
 Return this object synchronize lock.
 
virtual LuceneSignalPtr getSignal ()
 Return this object signal.
 
virtual void lock (int32_t timeout=0)
 Lock this object using an optional timeout.
 
virtual void unlock ()
 Unlock this object.
 
virtual bool holdsLock ()
 Returns true if this object is currently locked by current thread.
 
virtual void wait (int32_t timeout=0)
 Wait for signal using an optional timeout.
 
virtual void notifyAll ()
 Notify all threads waiting for signal.
 

Static Public Member Functions

static String _getClassName ()
 
- Static Public Member Functions inherited from Lucene::LogMergePolicy
static String _getClassName ()
 
- Static Public Member Functions inherited from Lucene::MergePolicy
static String _getClassName ()
 

Static Public Attributes

static const double DEFAULT_MIN_MERGE_MB
 Default minimum segment size.
 
static const double DEFAULT_MAX_MERGE_MB
 Default maximum segment size. A segment of this size or larger will never be merged.
 
- Static Public Attributes inherited from Lucene::LogMergePolicy
static const double LEVEL_LOG_SPAN
 Defines the allowed range of log(size) for each level. A level is computed by taking the max segment log size, minus LEVEL_LOG_SPAN, and finding all segments falling within that range.
 
static const int32_t DEFAULT_MERGE_FACTOR
 Default merge factor, which is how many segments are merged at a time.
 
static const int32_t DEFAULT_MAX_MERGE_DOCS
 Default maximum segment size. A segment of this size or larger will never be merged.
 
static const double DEFAULT_NO_CFS_RATIO
 Default noCFSRatio. If a merge's size is >= 10% of the index, then we disable compound file for it.
 

Protected Member Functions

virtual int64_t size (const SegmentInfoPtr &info)
 
- Protected Member Functions inherited from Lucene::LogMergePolicy
bool verbose ()
 
void message (const String &message)
 
int64_t sizeDocs (const SegmentInfoPtr &info)
 
int64_t sizeBytes (const SegmentInfoPtr &info)
 
bool isOptimized (const SegmentInfosPtr &infos, int32_t maxNumSegments, SetSegmentInfo segmentsToOptimize)
 
bool isOptimized (const SegmentInfoPtr &info)
 Returns true if this single info is optimized (has no pending norms or deletes, is in the same dir as the writer, and matches the current compound file setting.
 
OneMergePtr makeOneMerge (const SegmentInfosPtr &infos, const SegmentInfosPtr &infosToMerge)
 
- Protected Member Functions inherited from Lucene::LuceneObject
 LuceneObject ()
 

Additional Inherited Members

- Data Fields inherited from Lucene::LogMergePolicy
int64_t minMergeSize
 
int64_t maxMergeSize
 
int32_t maxMergeDocs
 
- Protected Attributes inherited from Lucene::LogMergePolicy
int32_t mergeFactor
 
double noCFSRatio
 
bool calibrateSizeByDeletes
 
bool _useCompoundFile
 
bool _useCompoundDocStore
 
- Protected Attributes inherited from Lucene::MergePolicy
IndexWriterWeakPtr _writer
 
- Protected Attributes inherited from Lucene::LuceneSync
SynchronizePtr objectLock
 
LuceneSignalPtr objectSignal
 

Detailed Description

This is a LogMergePolicy that measures size of a segment as the total byte size of the segment's files.

Constructor & Destructor Documentation

◆ LogByteSizeMergePolicy()

Lucene::LogByteSizeMergePolicy::LogByteSizeMergePolicy ( const IndexWriterPtr writer)

◆ ~LogByteSizeMergePolicy()

virtual Lucene::LogByteSizeMergePolicy::~LogByteSizeMergePolicy ( )
virtual

Member Function Documentation

◆ _getClassName()

static String Lucene::LogByteSizeMergePolicy::_getClassName ( )
inlinestatic

◆ getClassName()

virtual String Lucene::LogByteSizeMergePolicy::getClassName ( )
inlinevirtual

Reimplemented from Lucene::LogMergePolicy.

◆ getMaxMergeMB()

double Lucene::LogByteSizeMergePolicy::getMaxMergeMB ( )

Returns the largest segment (measured by total byte size of the segment's files, in MB) that may be merged with other segments.

See also
setMaxMergeMB

◆ getMinMergeMB()

double Lucene::LogByteSizeMergePolicy::getMinMergeMB ( )

Get the minimum size for a segment to remain un-merged.

See also
setMinMergeMB

◆ setMaxMergeMB()

void Lucene::LogByteSizeMergePolicy::setMaxMergeMB ( double  mb)

Determines the largest segment (measured by total byte size of the segment's files, in MB) that may be merged with other segments. Small values (eg., less than 50 MB) are best for interactive indexing, as this limits the length of pauses while indexing to a few seconds. Larger values are best for batched indexing and speedier searches.

Note that setMaxMergeDocs is also used to check whether a segment is too large for merging (it's either or).

◆ setMinMergeMB()

void Lucene::LogByteSizeMergePolicy::setMinMergeMB ( double  mb)

Sets the minimum size for the lowest level segments. Any segments below this size are considered to be on the same level (even if they vary drastically in size) and will be merged whenever there are mergeFactor of them. This effectively truncates the "long tail" of small segments that would otherwise be created into a single level. If you set this too large, it could greatly increase the merging cost during indexing (if you flush many small segments).

◆ shared_from_this()

boost::shared_ptr< LogByteSizeMergePolicy > Lucene::LogByteSizeMergePolicy::shared_from_this ( )
inline

◆ size()

virtual int64_t Lucene::LogByteSizeMergePolicy::size ( const SegmentInfoPtr info)
protectedvirtual

Field Documentation

◆ DEFAULT_MAX_MERGE_MB

const double Lucene::LogByteSizeMergePolicy::DEFAULT_MAX_MERGE_MB
static

Default maximum segment size. A segment of this size or larger will never be merged.

See also
setMaxMergeMB

◆ DEFAULT_MIN_MERGE_MB

const double Lucene::LogByteSizeMergePolicy::DEFAULT_MIN_MERGE_MB
static

Default minimum segment size.

See also
setMinMergeMB.

The documentation for this class was generated from the following file:

clucene.sourceforge.net