Package org.apache.bookkeeper.bookie

Class SyncThread

java.lang.Object

org.apache.bookkeeper.bookie.SyncThread

All Implemented Interfaces:

Checkpointer

class SyncThread
extends Object
implements Checkpointer

SyncThread is a background thread which help checkpointing ledger storage when a checkpoint is requested. After a ledger storage is checkpointed, the journal files added before checkpoint will be garbage collected.

After all data has been persisted to ledger index files and entry loggers, it is safe to complete a checkpoint by persisting the log marker to disk. If bookie failed after persist log mark, bookie is able to relay journal entries started from last log mark without losing any entries.

Those journal files whose id are less than the log id in last log mark, could be removed safely after persisting last log mark. We provide a setting to let user keeping number of old journal files which may be used for manual recovery in critical disaster.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) final CheckpointSource	checkpointSource
(package private) final LedgerDirsManager.LedgerDirsListener	dirsListener
(package private) final ScheduledExecutorService	executor
(package private) final LedgerStorage	ledgerStorage

Fields inherited from interface org.apache.bookkeeper.bookie.Checkpointer

NULL

Constructor Summary

Constructors

Constructor	Description
SyncThread(ServerConfiguration conf, LedgerDirsManager.LedgerDirsListener dirsListener, LedgerStorage ledgerStorage, CheckpointSource checkpointSource, StatsLogger statsLogger)

Method Summary

Modifier and Type	Method	Description
void	checkpoint(CheckpointSource.Checkpoint checkpoint)
void	disableCheckpoint()
protected void	doCheckpoint(CheckpointSource.Checkpoint checkpoint)
(package private) ScheduledExecutorService	getExecutor()
(package private) static ScheduledExecutorService	newExecutor()
Future	requestFlush()
void	resumeSync()	Resume sync thread.
(package private) void	shutdown()
void	start()
void	startCheckpoint(CheckpointSource.Checkpoint checkpoint)	Start checkpointing for a given checkpoint location.
void	suspendSync()	Suspend sync thread.

Methods inherited from class java.lang.Object

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

Field Details

executor

final ScheduledExecutorService executor

ledgerStorage

final LedgerStorage ledgerStorage

dirsListener

final LedgerDirsManager.LedgerDirsListener dirsListener

checkpointSource

final CheckpointSource checkpointSource

Constructor Details

SyncThread

public SyncThread(ServerConfiguration conf,
 LedgerDirsManager.LedgerDirsListener dirsListener,
 LedgerStorage ledgerStorage,
 CheckpointSource checkpointSource,
 StatsLogger statsLogger)

Method Details

newExecutor

static ScheduledExecutorService newExecutor()

startCheckpoint

public void startCheckpoint(CheckpointSource.Checkpoint checkpoint)

Description copied from interface: Checkpointer

Start checkpointing for a given checkpoint location.

Specified by:

startCheckpoint in interface Checkpointer

Parameters:

checkpoint - the checkpoint location to checkpoint.

doCheckpoint

protected void doCheckpoint(CheckpointSource.Checkpoint checkpoint)

requestFlush

public Future requestFlush()

checkpoint

public void checkpoint(CheckpointSource.Checkpoint checkpoint)

start

public void start()

Specified by:

start in interface Checkpointer

suspendSync

public void suspendSync()

Suspend sync thread. (for testing)

resumeSync

public void resumeSync()

Resume sync thread. (for testing)

disableCheckpoint

public void disableCheckpoint()

shutdown

void shutdown()
       throws InterruptedException

Throws:

InterruptedException

getExecutor

ScheduledExecutorService getExecutor()