com.gigaspaces.internal.server.space.redolog

Class MemoryRedoLogFile<T extends IReplicationOrderedPacket>

java.lang.Object

com.gigaspaces.internal.server.space.redolog.MemoryRedoLogFile<T>

All Implemented Interfaces:

IRedoLogFileStatistics, IRedoLogFile<T>

public class MemoryRedoLogFile<T extends IReplicationOrderedPacket>
extends Object
implements IRedoLogFile<T>

A memory only based implementation of the IRedoLogFile interface. Packets are stored only in the jvm memory

Since:

7.1

Author:

eitany

Constructor Summary

Constructors

Constructor and Description
MemoryRedoLogFile(String name, AbstractSingleFileGroupBacklog groupBacklog)

Method Summary

Modifier and Type	Method and Description
void	add(T replicationPacket) Add a replication packet to the file as the latest packet
void	close() Closes the redo log file
void	deleteOldestPackets(long packetsCount) Deletes the oldest packets, starting from the oldest up until the specified batch size
long	getApproximateSize() Gets an approximation of the number of replication packets held in the file, implementation of this method should not assume a reader lock is held and hence can return a result which is not accurate if it cannot do so without a lock.
long	getExternalStoragePacketsCount()
long	getExternalStoragePacketsWeight()
long	getExternalStorageSpaceUsed()
long	getMemoryPacketsCount()
long	getMemoryPacketsWeight()
T	getOldest()
long	getWeight()
boolean	isEmpty()
CompactionResult	performCompaction(long from, long to)
ReadOnlyIterator<T>	readOnlyIterator(long fromKey)
T	removeOldest() Remove and returns the oldest replication packet in the file
long	size()
void	validateIntegrity() Validates the integrity of the redo log file

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.gigaspaces.internal.server.space.redolog.IRedoLogFile

flushToStorage

Constructor Detail

MemoryRedoLogFile

public MemoryRedoLogFile(String name,
                         AbstractSingleFileGroupBacklog groupBacklog)

Method Detail

add

public void add(T replicationPacket)

Description copied from interface: IRedoLogFile

Add a replication packet to the file as the latest packet

Specified by:

add in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Parameters:

replicationPacket - packet to add

getOldest

public T getOldest()

Specified by:

getOldest in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Returns:

Gets the oldest replication packet in the file

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Returns:

true if the file has no replication packets stored

getExternalStorageSpaceUsed

public long getExternalStorageSpaceUsed()

Specified by:

getExternalStorageSpaceUsed in interface IRedoLogFileStatistics

Returns:

used space in bytes which is external to the jvm

getExternalStoragePacketsCount

public long getExternalStoragePacketsCount()

Specified by:

getExternalStoragePacketsCount in interface IRedoLogFileStatistics

Returns:

number of packets held in storage

getMemoryPacketsWeight

public long getMemoryPacketsWeight()

Specified by:

getMemoryPacketsWeight in interface IRedoLogFileStatistics

Returns:

total weight of packets held in memory

getExternalStoragePacketsWeight

public long getExternalStoragePacketsWeight()

Specified by:

getExternalStoragePacketsWeight in interface IRedoLogFileStatistics

Returns:

total weight of packets held in external storage

getMemoryPacketsCount

public long getMemoryPacketsCount()

Specified by:

getMemoryPacketsCount in interface IRedoLogFileStatistics

Returns:

number of packets held in memory

readOnlyIterator

public ReadOnlyIterator<T> readOnlyIterator(long fromKey)

Specified by:

readOnlyIterator in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Parameters:

fromKey - index to start from

Returns:

read only iterator over the packets in the file that will start from the given index, where 0 specified the oldest packet

removeOldest

public T removeOldest()

Description copied from interface: IRedoLogFile

Remove and returns the oldest replication packet in the file

Specified by:

removeOldest in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Returns:

returns the oldest replication packet in the file

size

public long size()

Specified by:

size in interface IRedoLogFileStatistics

Specified by:

size in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Returns:

the number of replication packets held in the file

getApproximateSize

public long getApproximateSize()

Description copied from interface: IRedoLogFile

Gets an approximation of the number of replication packets held in the file, implementation of this method should not assume a reader lock is held and hence can return a result which is not accurate if it cannot do so without a lock.

Specified by:

getApproximateSize in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Returns:

an approximation of the replication packets held in the file

deleteOldestPackets

public void deleteOldestPackets(long packetsCount)

Description copied from interface: IRedoLogFile

Deletes the oldest packets, starting from the oldest up until the specified batch size

Specified by:

deleteOldestPackets in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Parameters:

packetsCount - number of oldest packets to delete

validateIntegrity

public void validateIntegrity()
                       throws RedoLogFileCompromisedException

Description copied from interface: IRedoLogFile

Validates the integrity of the redo log file

Specified by:

validateIntegrity in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Throws:

RedoLogFileCompromisedException

close

public void close()

Description copied from interface: IRedoLogFile

Closes the redo log file

Specified by:

close in interface IRedoLogFile<T extends IReplicationOrderedPacket>

getWeight

public long getWeight()

Specified by:

getWeight in interface IRedoLogFile<T extends IReplicationOrderedPacket>

performCompaction

public CompactionResult performCompaction(long from,
                                          long to)

Specified by:

performCompaction in interface IRedoLogFile<T extends IReplicationOrderedPacket>

Parameters:

from - key to start searching transient packet from

to - key to end searching transient packet from

Returns:

number of discarded packets