org.apache.hadoop.hbase.regionserver

Class ImmutableMemStoreLAB

java.lang.Object

org.apache.hadoop.hbase.regionserver.ImmutableMemStoreLAB

All Implemented Interfaces:

MemStoreLAB

@InterfaceAudience.Private
public class ImmutableMemStoreLAB
extends Object
implements MemStoreLAB

A MemStoreLAB implementation which wraps N MemStoreLABs. Its main duty is in proper managing the close of the individual MemStoreLAB. This is treated as an immutable one and so do not allow to add any more Cells into it. copyCellInto(Cell) throws Exception

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	closed
private List<MemStoreLAB>	mslabs
private AtomicInteger	openScannerCount

Fields inherited from interface org.apache.hadoop.hbase.regionserver.MemStoreLAB

CHUNK_POOL_INITIALSIZE_KEY, CHUNK_POOL_MAXSIZE_KEY, CHUNK_SIZE_DEFAULT, CHUNK_SIZE_KEY, INDEX_CHUNK_PERCENTAGE_DEFAULT, INDEX_CHUNK_PERCENTAGE_KEY, MAX_ALLOC_DEFAULT, MAX_ALLOC_KEY, MSLAB_CLASS_NAME, POOL_INITIAL_SIZE_DEFAULT, POOL_MAX_SIZE_DEFAULT, USEMSLAB_DEFAULT, USEMSLAB_KEY

Constructor Summary

Constructors

Constructor and Description
ImmutableMemStoreLAB(List<MemStoreLAB> mslabs)

Method Summary

Modifier and Type	Method and Description
private void	checkAndCloseMSLABs(int openScanners)
void	close() Close instance since it won't be used any more, try to put the chunks back to pool
Cell	copyCellInto(Cell cell) Allocates slice in this LAB and copy the passed Cell into this area.
void	decScannerCount() Called when closing a scanner on the data of this MemStoreLAB
Cell	forceCopyOfBigCellInto(Cell cell) The process of merging assumes all cells are allocated on mslab.
Chunk	getNewExternalChunk(ChunkCreator.ChunkType chunkType)
Chunk	getNewExternalChunk(int size)
void	incScannerCount() Called when opening a scanner on the data of this MemStoreLAB
boolean	isOffHeap()
boolean	isOnHeap()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.hbase.regionserver.MemStoreLAB

isEnabled, newInstance

Field Detail

openScannerCount

private final AtomicInteger openScannerCount

closed

private volatile boolean closed

mslabs

private final List<MemStoreLAB> mslabs

Constructor Detail

ImmutableMemStoreLAB

public ImmutableMemStoreLAB(List<MemStoreLAB> mslabs)

Method Detail

copyCellInto

public Cell copyCellInto(Cell cell)

Description copied from interface: MemStoreLAB

Allocates slice in this LAB and copy the passed Cell into this area. Returns new Cell instance over the copied the data. When this MemStoreLAB can not copy this Cell, it returns null.

Specified by:

copyCellInto in interface MemStoreLAB

forceCopyOfBigCellInto

public Cell forceCopyOfBigCellInto(Cell cell)

The process of merging assumes all cells are allocated on mslab. There is a rare case in which the first immutable segment, participating in a merge, is a CSLM. Since the CSLM hasn't been flattened yet, and there is no point in flattening it (since it is going to be merged), its big cells (for whom size > maxAlloc) must be copied into mslab. This method copies the passed cell into the first mslab in the mslabs list, returning either a new cell instance over the copied data, or null when this cell cannt be copied.

Specified by:

forceCopyOfBigCellInto in interface MemStoreLAB

getNewExternalChunk

public Chunk getNewExternalChunk(ChunkCreator.ChunkType chunkType)

Specified by:

getNewExternalChunk in interface MemStoreLAB

getNewExternalChunk

public Chunk getNewExternalChunk(int size)

Specified by:

getNewExternalChunk in interface MemStoreLAB

close

public void close()

Description copied from interface: MemStoreLAB

Close instance since it won't be used any more, try to put the chunks back to pool

Specified by:

close in interface MemStoreLAB

checkAndCloseMSLABs

private void checkAndCloseMSLABs(int openScanners)

incScannerCount

public void incScannerCount()

Description copied from interface: MemStoreLAB

Called when opening a scanner on the data of this MemStoreLAB

Specified by:

incScannerCount in interface MemStoreLAB

decScannerCount

public void decScannerCount()

Description copied from interface: MemStoreLAB

Called when closing a scanner on the data of this MemStoreLAB

Specified by:

decScannerCount in interface MemStoreLAB

isOnHeap

public boolean isOnHeap()

Specified by:

isOnHeap in interface MemStoreLAB

isOffHeap

public boolean isOffHeap()

Specified by:

isOffHeap in interface MemStoreLAB