com.bigdata.rwstore

Class RWWriteCacheService

java.lang.Object

com.bigdata.io.writecache.WriteCacheService

com.bigdata.rwstore.RWWriteCacheService

All Implemented Interfaces:

IWriteCache, IWriteCacheManager

public class RWWriteCacheService
extends WriteCacheService
implements IWriteCacheManager

Defines the WriteCacheService to be used by the RWStore.

Author:

mgc

Nested Class Summary

Nested classes/interfaces inherited from class com.bigdata.io.writecache.WriteCacheService

WriteCacheService.AsynchronousCloseException

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.apache.log4j.Logger	log

Constructor Summary

Constructors

Constructor and Description
RWWriteCacheService(int nbuffers, int minCleanListSize, int readBuffers, boolean prefixWrites, int compactionThreshold, int hotCacheSize, int hotCacheThreshold, long fileExtent, IReopenChannel<? extends Channel> opener, Quorum quorum, IBackingReader reader)

Method Summary

Methods

Modifier and Type	Method and Description
protected boolean	canCompact() The scattered write cache supports compaction.
WriteCache	newWriteCache(IBufferAccess buf, boolean useChecksum, boolean bufferHasData, IReopenChannel<? extends Channel> opener, long fileExtent) Provide default WriteCache.FileChannelScatteredWriteCache.
boolean	removeWriteToAddr(long address, int latchedAddr)

Methods inherited from class com.bigdata.io.writecache.WriteCacheService

_readFromCache, addrDebugInfo, clearWrite, close, debugAddrs, finalized, flush, flush, getCounters, getQuorum, getSendCount, getSequence, installReads, isPresent, newWriteTask, read, reset, resetAndClear, resetSequence, setExtent, write, write, writeLargeRecord

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.log4j.Logger log

Constructor Detail

RWWriteCacheService

public RWWriteCacheService(int nbuffers,
                   int minCleanListSize,
                   int readBuffers,
                   boolean prefixWrites,
                   int compactionThreshold,
                   int hotCacheSize,
                   int hotCacheThreshold,
                   long fileExtent,
                   IReopenChannel<? extends Channel> opener,
                   Quorum quorum,
                   IBackingReader reader)
                    throws InterruptedException,
                           IOException

Throws:

InterruptedException

IOException

Method Detail

canCompact

protected final boolean canCompact()

The scattered write cache supports compaction.

Overrides:

canCompact in class WriteCacheService

newWriteCache

public WriteCache newWriteCache(IBufferAccess buf,
                       boolean useChecksum,
                       boolean bufferHasData,
                       IReopenChannel<? extends Channel> opener,
                       long fileExtent)
                         throws InterruptedException

Provide default WriteCache.FileChannelScatteredWriteCache.

Note: This is used by the unit tests, but not by the RWStore.

Specified by:

newWriteCache in class WriteCacheService

Parameters:

buf - The backing buffer (optional).

useChecksum - true iff record level checksums are enabled.

bufferHasData - true iff the buffer has data to be written onto the local persistence store (from a replicated write).

opener - The object which knows how to re-open the backing channel (required).

fileExtent - The then current extent of the backing file.

Returns:

A WriteCache wrapping that buffer and able to write on that channel.

Throws:

InterruptedException

removeWriteToAddr

public boolean removeWriteToAddr(long address,
                        int latchedAddr)

Specified by:

removeWriteToAddr in interface IWriteCacheManager