org.apache.hadoop.hbase.master.snapshot

类 TakeSnapshotHandler

java.lang.Object

org.apache.hadoop.hbase.executor.EventHandler

org.apache.hadoop.hbase.master.snapshot.TakeSnapshotHandler

所有已实现的接口:

Comparable<Runnable>, Runnable, ForeignExceptionSnare, SnapshotSentinel

直接已知子类:

DisabledTableSnapshotHandler, EnabledTableSnapshotHandler

@InterfaceAudience.Private
public abstract class TakeSnapshotHandler
extends EventHandler
implements SnapshotSentinel, ForeignExceptionSnare

A handler for taking snapshots from the master. This is not a subclass of TableEventHandler because using that would incur an extra hbase:meta scan. The snapshotRegions(List) call should get implemented for each snapshot flavor.

字段概要

字段

限定符和类型	字段和说明
protected org.apache.hadoop.conf.Configuration	conf
protected org.apache.hadoop.fs.FileSystem	fs
protected TableDescriptor	htd
protected MasterServices	master
protected MetricsSnapshot	metricsSnapshot
protected ForeignExceptionDispatcher	monitor
protected org.apache.hadoop.fs.Path	rootDir
protected org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription	snapshot
protected SnapshotManager	snapshotManager
protected SnapshotManifest	snapshotManifest
protected TableName	snapshotTable
protected MonitoredTask	status
protected org.apache.hadoop.fs.Path	workingDir

从类继承的字段 org.apache.hadoop.hbase.executor.EventHandler

eventType, seqids, server, waitingTimeForEvents

构造器概要

构造器

构造器和说明
TakeSnapshotHandler(org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription snapshot, MasterServices masterServices, SnapshotManager snapshotManager)

方法概要

限定符和类型	方法和说明
void	cancel(String why) Actively cancel a running snapshot.
void	completeSnapshot(org.apache.hadoop.fs.Path snapshotDir, org.apache.hadoop.fs.Path workingDir, org.apache.hadoop.fs.FileSystem fs) Reset the manager to allow another snapshot to proceed
protected abstract boolean	downgradeToSharedTableLock() When taking snapshot, first we must acquire the exclusive table lock to confirm that there are no ongoing merge/split procedures.
long	getCompletionTimestamp()
ForeignException	getException() Get the value of the captured exception.
ForeignException	getExceptionIfFailed() Get the exception that caused the snapshot to fail, if the snapshot has failed.
org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription	getSnapshot()
boolean	hasException() Non-exceptional form of ForeignExceptionSnare.rethrowException().
boolean	isFinished() Check to see if the snapshot is finished, where finished may be success or failure.
TakeSnapshotHandler	prepare() Event handlers should do all the necessary checks in this method (rather than in the constructor, or in process()) so that the caller, which is mostly executed in the ipc context can fail fast.
void	process() Execute the core common portions of taking a snapshot.
void	rethrowException() Rethrow an exception currently held by the ForeignExceptionSnare.
void	rethrowExceptionIfFailed() Rethrow the exception returned by SnapshotSentinel.getExceptionIfFailed().
protected void	snapshotDisabledRegion(RegionInfo regionInfo) Take a snapshot of the specified disabled region
protected abstract void	snapshotRegions(List<Pair<RegionInfo,ServerName>> regions) Snapshot the specified regions

从类继承的方法 org.apache.hadoop.hbase.executor.EventHandler

compareTo, getEventType, getInformativeName, getPriority, getSeqid, handleException, run, toString

从类继承的方法 java.lang.Object

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

字段详细资料

master

protected final MasterServices master

metricsSnapshot

protected final MetricsSnapshot metricsSnapshot

snapshot

protected final org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription snapshot

conf

protected final org.apache.hadoop.conf.Configuration conf

fs

protected final org.apache.hadoop.fs.FileSystem fs

rootDir

protected final org.apache.hadoop.fs.Path rootDir

workingDir

protected final org.apache.hadoop.fs.Path workingDir

monitor

protected final ForeignExceptionDispatcher monitor

status

protected final MonitoredTask status

snapshotTable

protected final TableName snapshotTable

snapshotManifest

protected final SnapshotManifest snapshotManifest

snapshotManager

protected final SnapshotManager snapshotManager

htd

protected TableDescriptor htd

构造器详细资料

TakeSnapshotHandler

public TakeSnapshotHandler(org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription snapshot,
                           MasterServices masterServices,
                           SnapshotManager snapshotManager)

参数:

snapshot - descriptor of the snapshot to take

masterServices - master services provider

方法详细资料

prepare

public TakeSnapshotHandler prepare()
                            throws Exception

从类复制的说明: EventHandler

Event handlers should do all the necessary checks in this method (rather than in the constructor, or in process()) so that the caller, which is mostly executed in the ipc context can fail fast. Process is executed async from the client ipc, so this method gives a quick chance to do some basic checks. Should be called after constructing the EventHandler, and before process().

覆盖:

prepare 在类中 EventHandler

返回:

the instance of this class

抛出:

Exception - when something goes wrong

process

public void process()

Execute the core common portions of taking a snapshot. The snapshotRegions(List) call should get implemented for each snapshot flavor.

指定者:

process 在类中 EventHandler

completeSnapshot

public void completeSnapshot(org.apache.hadoop.fs.Path snapshotDir,
                             org.apache.hadoop.fs.Path workingDir,
                             org.apache.hadoop.fs.FileSystem fs)
                      throws SnapshotCreationException,
                             IOException

Reset the manager to allow another snapshot to proceed

参数:

snapshotDir - final path of the snapshot

workingDir - directory where the in progress snapshot was built

fs - FileSystem where the snapshot was built

抛出:

SnapshotCreationException - if the snapshot could not be moved

IOException - the filesystem could not be reached

downgradeToSharedTableLock

protected abstract boolean downgradeToSharedTableLock()

When taking snapshot, first we must acquire the exclusive table lock to confirm that there are no ongoing merge/split procedures. But later, we should try our best to release the exclusive lock as this may hurt the availability, because we need to hold the shared lock when assigning regions.

See HBASE-21480 for more details.

snapshotRegions

protected abstract void snapshotRegions(List<Pair<RegionInfo,ServerName>> regions)
                                 throws IOException,
                                        org.apache.zookeeper.KeeperException

Snapshot the specified regions

抛出:

IOException

org.apache.zookeeper.KeeperException

snapshotDisabledRegion

protected void snapshotDisabledRegion(RegionInfo regionInfo)
                               throws IOException

Take a snapshot of the specified disabled region

抛出:

IOException

cancel

public void cancel(String why)

从接口复制的说明: SnapshotSentinel

Actively cancel a running snapshot.

指定者:

cancel 在接口中 SnapshotSentinel

参数:

why - Reason for cancellation.

isFinished

public boolean isFinished()

从接口复制的说明: SnapshotSentinel

Check to see if the snapshot is finished, where finished may be success or failure.

指定者:

isFinished 在接口中 SnapshotSentinel

返回:

false if the snapshot is still in progress, true if the snapshot has finished

getCompletionTimestamp

public long getCompletionTimestamp()

指定者:

getCompletionTimestamp 在接口中 SnapshotSentinel

返回:

-1 if the snapshot is in progress, otherwise the completion timestamp.

getSnapshot

public org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription getSnapshot()

指定者:

getSnapshot 在接口中 SnapshotSentinel

返回:

the description of the snapshot being run

getExceptionIfFailed

public ForeignException getExceptionIfFailed()

从接口复制的说明: SnapshotSentinel

Get the exception that caused the snapshot to fail, if the snapshot has failed.

指定者:

getExceptionIfFailed 在接口中 SnapshotSentinel

返回:

ForeignException that caused the snapshot to fail, or null if the snapshot is still in progress or has succeeded

rethrowExceptionIfFailed

public void rethrowExceptionIfFailed()
                              throws ForeignException

从接口复制的说明: SnapshotSentinel

Rethrow the exception returned by SnapshotSentinel.getExceptionIfFailed(). If there is no exception this is a no-op.

指定者:

rethrowExceptionIfFailed 在接口中 SnapshotSentinel

抛出:

ForeignException - all exceptions from remote sources are procedure exceptions

rethrowException

public void rethrowException()
                      throws ForeignException

从接口复制的说明: ForeignExceptionSnare

Rethrow an exception currently held by the ForeignExceptionSnare. If there is no exception this is a no-op

指定者:

rethrowException 在接口中 ForeignExceptionSnare

抛出:

ForeignException - all exceptions from remote sources are procedure exceptions

hasException

public boolean hasException()

从接口复制的说明: ForeignExceptionSnare

Non-exceptional form of ForeignExceptionSnare.rethrowException(). Checks to see if any process to which the exception checkers is bound has created an error that would cause a failure.

指定者:

hasException 在接口中 ForeignExceptionSnare

返回:

true if there has been an error,false otherwise

getException

public ForeignException getException()

从接口复制的说明: ForeignExceptionSnare

Get the value of the captured exception.

指定者:

getException 在接口中 ForeignExceptionSnare

返回:

the captured foreign exception or null if no exception captured.