org.apache.jackrabbit.oak.plugins.segment

Class SegmentTracker

java.lang.Object

org.apache.jackrabbit.oak.plugins.segment.SegmentTracker

public class SegmentTracker
extends java.lang.Object

Tracker of references to segment identifiers and segment instances that are currently kept in memory.

It is also responsible to cache segment objects in memory.

Constructor Summary

Constructors

Constructor and Description
SegmentTracker(SegmentStore store)
SegmentTracker(SegmentStore store, int cacheSizeMB, SegmentVersion version)
SegmentTracker(SegmentStore store, SegmentVersion version)

Method Summary

Modifier and Type	Method and Description
void	clearCache() Clear the caches
void	clearSegmentIdTables(CompactionStrategy strategy)
void	collectBlobReferences(ReferenceCollector collector) Finds all external blob references that are currently accessible in this repository and adds them to the given collector.
SegmentWriter	createSegmentWriter(java.lang.String wid)
CompactionMap	getCompactionMap()
java.util.Set<SegmentId>	getReferencedSegmentIds() Returns all segment identifiers that are currently referenced in memory.
CacheStats	getSegmentCacheStats()
SegmentId	getSegmentId(long msb, long lsb)
SegmentStore	getStore()
CacheStats	getStringCacheStats()
SegmentWriter	getWriter()
void	setCompactionMap(PartialCompactionMap map)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SegmentTracker

public SegmentTracker(SegmentStore store,
                      int cacheSizeMB,
                      SegmentVersion version)

SegmentTracker

public SegmentTracker(SegmentStore store,
                      SegmentVersion version)

SegmentTracker

public SegmentTracker(SegmentStore store)

Method Detail

createSegmentWriter

public final SegmentWriter createSegmentWriter(java.lang.String wid)

Returns:

a new SegmentWriter instance for writing to this store.

getSegmentCacheStats

public CacheStats getSegmentCacheStats()

getStringCacheStats

public CacheStats getStringCacheStats()

getWriter

public SegmentWriter getWriter()

getStore

public SegmentStore getStore()

clearCache

public void clearCache()

Clear the caches

setCompactionMap

public void setCompactionMap(PartialCompactionMap map)

getCompactionMap

public CompactionMap getCompactionMap()

getReferencedSegmentIds

public java.util.Set<SegmentId> getReferencedSegmentIds()

Returns all segment identifiers that are currently referenced in memory.

Returns:

referenced segment identifiers

collectBlobReferences

public void collectBlobReferences(ReferenceCollector collector)

Finds all external blob references that are currently accessible in this repository and adds them to the given collector. Useful for collecting garbage in an external data store.

Note that this method only collects blob references that are already stored in the repository (at the time when this method is called), so the garbage collector will need some other mechanism for tracking in-memory references and references stored while this method is running.

getSegmentId

public SegmentId getSegmentId(long msb,
                              long lsb)

Parameters:

msb -

lsb -

Returns:

the segment id

clearSegmentIdTables

public void clearSegmentIdTables(CompactionStrategy strategy)