Module org.apache.lucene.core

Package org.apache.lucene.index

Class ReaderPool

java.lang.Object

org.apache.lucene.index.ReaderPool

All Implemented Interfaces:

Closeable, AutoCloseable

final class ReaderPool
extends Object
implements Closeable

Holds shared SegmentReader instances. IndexWriter uses SegmentReaders for 1) applying deletes/DV updates, 2) doing merges, 3) handing out a real-time reader. This pool reuses instances of the SegmentReaders in all these places if it is in "near real-time mode" (getReader() has been called on this instance).

Field Summary

Fields

Modifier and Type	Field	Description
private final AtomicBoolean	closed
private final LongSupplier	completedDelGenSupplier
private final Directory	directory
private final FieldInfos.FieldNumbers	fieldNumbers
private final InfoStream	infoStream
private final Directory	originalDirectory
private boolean	poolReaders
private final Map<SegmentCommitInfo,ReadersAndUpdates>	readerMap
private final SegmentInfos	segmentInfos
private final String	softDeletesField

Constructor Summary

Constructors

Constructor	Description
ReaderPool(Directory directory, Directory originalDirectory, SegmentInfos segmentInfos, FieldInfos.FieldNumbers fieldNumbers, LongSupplier completedDelGenSupplier, InfoStream infoStream, String softDeletesField, StandardDirectoryReader reader)

Method Summary

Modifier and Type	Method	Description
(package private) boolean	anyDeletions()	Returns true iff any of the buffered readers and updates has at least one pending delete
(package private) boolean	anyDocValuesChanges()	Returns true iff there are any buffered doc values updates.
(package private) boolean	assertInfoIsLive(SegmentCommitInfo info)	Asserts this info still exists in IW's segment infos
void	close()
(package private) boolean	commit(SegmentInfos infos)	Commit live docs changes for the segment readers for the provided infos.
(package private) boolean	drop(SegmentCommitInfo info)	Drops reader for the given SegmentCommitInfo if it's pooled
(package private) void	dropAll()	Remove all our references to readers, and commits any pending changes.
(package private) void	enableReaderPooling()	Enables reader pooling for this pool.
(package private) ReadersAndUpdates	get(SegmentCommitInfo info, boolean create)	Obtain a ReadersAndLiveDocs instance from the readerPool.
(package private) List<ReadersAndUpdates>	getReadersByRam()	Returns a list of all currently maintained ReadersAndUpdates sorted by it's ram consumption largest to smallest.
(package private) boolean	isReaderPoolingEnabled()
private PendingDeletes	newPendingDeletes(SegmentCommitInfo info)
private PendingDeletes	newPendingDeletes(SegmentReader reader, SegmentCommitInfo info)
private boolean	noDups()
(package private) long	ramBytesUsed()	Returns the sum of the ram used by all the buffered readers and updates in MB
(package private) boolean	release(ReadersAndUpdates rld, boolean assertInfoLive)	Releases the ReadersAndUpdates.
(package private) boolean	writeAllDocValuesUpdates()	Writes all doc values updates to disk if there are any.
(package private) boolean	writeDocValuesUpdatesForMerge(List<SegmentCommitInfo> infos)	Writes all doc values updates to disk if there are any.

Methods inherited from class java.lang.Object

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

Field Details

readerMap

private final Map<SegmentCommitInfo,ReadersAndUpdates> readerMap

directory

private final Directory directory

originalDirectory

private final Directory originalDirectory

fieldNumbers

private final FieldInfos.FieldNumbers fieldNumbers

completedDelGenSupplier

private final LongSupplier completedDelGenSupplier

infoStream

private final InfoStream infoStream

segmentInfos

private final SegmentInfos segmentInfos

softDeletesField

private final String softDeletesField

poolReaders

private volatile boolean poolReaders

closed

private final AtomicBoolean closed

Constructor Details

ReaderPool

ReaderPool(Directory directory,
 Directory originalDirectory,
 SegmentInfos segmentInfos,
 FieldInfos.FieldNumbers fieldNumbers,
 LongSupplier completedDelGenSupplier,
 InfoStream infoStream,
 String softDeletesField,
 StandardDirectoryReader reader)
    throws IOException

Throws:

IOException

Method Details

assertInfoIsLive

boolean assertInfoIsLive(SegmentCommitInfo info)

Asserts this info still exists in IW's segment infos

drop

boolean drop(SegmentCommitInfo info)
      throws IOException

Drops reader for the given SegmentCommitInfo if it's pooled

Returns:

true if a reader is pooled

Throws:

IOException

ramBytesUsed

long ramBytesUsed()

Returns the sum of the ram used by all the buffered readers and updates in MB

anyDeletions

boolean anyDeletions()

Returns true iff any of the buffered readers and updates has at least one pending delete

enableReaderPooling

void enableReaderPooling()

Enables reader pooling for this pool. This should be called once the readers in this pool are shared with an outside resource like an NRT reader. Once reader pooling is enabled a ReadersAndUpdates will be kept around in the reader pool on calling release(ReadersAndUpdates, boolean) until the segment get dropped via calls to drop(SegmentCommitInfo) or dropAll() or close(). Reader pooling is disabled upon construction but can't be disabled again once it's enabled.

isReaderPoolingEnabled

boolean isReaderPoolingEnabled()

release

boolean release(ReadersAndUpdates rld,
 boolean assertInfoLive)
         throws IOException

Releases the ReadersAndUpdates. This should only be called if the get(SegmentCommitInfo, boolean) is called with the create paramter set to true.

Returns:

true if any files were written by this release call.

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

writeAllDocValuesUpdates

boolean writeAllDocValuesUpdates()
                          throws IOException

Writes all doc values updates to disk if there are any.

Returns:

true iff any files where written

Throws:

IOException

writeDocValuesUpdatesForMerge

boolean writeDocValuesUpdatesForMerge(List<SegmentCommitInfo> infos)
                               throws IOException

Writes all doc values updates to disk if there are any.

Returns:

true iff any files where written

Throws:

IOException

getReadersByRam

List<ReadersAndUpdates> getReadersByRam()

Returns a list of all currently maintained ReadersAndUpdates sorted by it's ram consumption largest to smallest. This list can also contain readers that don't consume any ram at this point ie. don't have any updates buffered.

dropAll

void dropAll()
      throws IOException

Remove all our references to readers, and commits any pending changes.

Throws:

IOException

commit

boolean commit(SegmentInfos infos)
        throws IOException

Commit live docs changes for the segment readers for the provided infos.

Throws:

IOException - If there is a low-level I/O error

anyDocValuesChanges

boolean anyDocValuesChanges()

Returns true iff there are any buffered doc values updates. Otherwise false .

get

ReadersAndUpdates get(SegmentCommitInfo info,
 boolean create)

Obtain a ReadersAndLiveDocs instance from the readerPool. If create is true, you must later call release(ReadersAndUpdates, boolean).

newPendingDeletes

private PendingDeletes newPendingDeletes(SegmentCommitInfo info)

newPendingDeletes

private PendingDeletes newPendingDeletes(SegmentReader reader,
 SegmentCommitInfo info)

noDups

private boolean noDups()