org.apache.hadoop.hbase.regionserver

Class MemStoreCompactor

java.lang.Object

org.apache.hadoop.hbase.regionserver.MemStoreCompactor

@InterfaceAudience.Private
public class MemStoreCompactor
extends Object

The ongoing MemStore Compaction manager, dispatches a solo running compaction and interrupts the compaction if requested. The compaction is interrupted and stopped by CompactingMemStore, for example when another compaction needs to be started. Prior to compaction the MemStoreCompactor evaluates the compacting ratio and aborts the compaction if it is not worthy. The MemStoreScanner is used to traverse the compaction pipeline. The MemStoreScanner is included in internal store scanner, where all compaction logic is implemented. Threads safety: It is assumed that the compaction pipeline is immutable, therefore no special synchronization is required.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MemStoreCompactor.Action Types of actions to be done on the pipeline upon MemStoreCompaction invocation.

Field Summary

Fields

Modifier and Type	Field and Description
static int	COMPACTING_MEMSTORE_THRESHOLD_DEFAULT
static String	COMPACTING_MEMSTORE_THRESHOLD_KEY
static long	DEEP_OVERHEAD

Constructor Summary

Constructors

Constructor and Description
MemStoreCompactor(CompactingMemStore compactingMemStore, MemoryCompactionPolicy compactionPolicy)

Method Summary

Modifier and Type	Method and Description
boolean	isIndexCompaction() ---------------------------------------------------------------------- The interface to check whether user requested the index-compaction
boolean	start() ---------------------------------------------------------------------- The request to dispatch the compaction asynchronous task.
void	stop() ---------------------------------------------------------------------- The request to cancel the compaction asynchronous task The compaction may still happen if the request was sent too late Non-blocking request

Methods inherited from class java.lang.Object

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

Field Detail

COMPACTING_MEMSTORE_THRESHOLD_KEY

public static final String COMPACTING_MEMSTORE_THRESHOLD_KEY

See Also:

Constant Field Values

COMPACTING_MEMSTORE_THRESHOLD_DEFAULT

public static final int COMPACTING_MEMSTORE_THRESHOLD_DEFAULT

See Also:

Constant Field Values

DEEP_OVERHEAD

public static final long DEEP_OVERHEAD

Constructor Detail

MemStoreCompactor

public MemStoreCompactor(CompactingMemStore compactingMemStore,
                         MemoryCompactionPolicy compactionPolicy)

Method Detail

start

public boolean start()
              throws IOException

---------------------------------------------------------------------- The request to dispatch the compaction asynchronous task. The method returns true if compaction was successfully dispatched, or false if there is already an ongoing compaction or no segments to compact.

Throws:

IOException

stop

public void stop()

---------------------------------------------------------------------- The request to cancel the compaction asynchronous task The compaction may still happen if the request was sent too late Non-blocking request

isIndexCompaction

public boolean isIndexCompaction()

---------------------------------------------------------------------- The interface to check whether user requested the index-compaction