org.apache.flink.streaming.api.environment

Class CheckpointConfig

java.lang.Object

org.apache.flink.streaming.api.environment.CheckpointConfig

All Implemented Interfaces:

Serializable

@Public
public class CheckpointConfig
extends Object
implements Serializable

Configuration that captures all checkpointing related settings.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CheckpointConfig.ExternalizedCheckpointCleanup Cleanup behaviour for externalized checkpoints when the job is cancelled.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_MAX_CONCURRENT_CHECKPOINTS The default limit of concurrently happening checkpoints: one.
static long	DEFAULT_MIN_PAUSE_BETWEEN_CHECKPOINTS The default minimum pause to be made between checkpoints: none.
static CheckpointingMode	DEFAULT_MODE The default checkpoint mode: exactly once.
static long	DEFAULT_TIMEOUT The default timeout of a checkpoint attempt: 10 minutes.

Constructor Summary

Constructors

Constructor and Description
CheckpointConfig()

Method Summary

Methods

Modifier and Type	Method and Description
void	enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup cleanupMode) Enables checkpoints to be persisted externally.
CheckpointingMode	getCheckpointingMode() Gets the checkpointing mode (exactly-once vs.
long	getCheckpointInterval() Gets the interval in which checkpoints are periodically scheduled.
long	getCheckpointTimeout() Gets the maximum time that a checkpoint may take before being discarded.
CheckpointConfig.ExternalizedCheckpointCleanup	getExternalizedCheckpointCleanup() Returns the cleanup behaviour for externalized checkpoints.
int	getMaxConcurrentCheckpoints() Gets the maximum number of checkpoint attempts that may be in progress at the same time.
long	getMinPauseBetweenCheckpoints() Gets the minimal pause between checkpointing attempts.
boolean	isCheckpointingEnabled() Checks whether checkpointing is enabled.
boolean	isExternalizedCheckpointsEnabled() Returns whether checkpoints should be persisted externally.
boolean	isForceCheckpointing() Deprecated. This will be removed once iterations properly participate in checkpointing.
void	setCheckpointingMode(CheckpointingMode checkpointingMode) Sets the checkpointing mode (exactly-once vs.
void	setCheckpointInterval(long checkpointInterval) Sets the interval in which checkpoints are periodically scheduled.
void	setCheckpointTimeout(long checkpointTimeout) Sets the maximum time that a checkpoint may take before being discarded.
void	setForceCheckpointing(boolean forceCheckpointing) Deprecated. This will be removed once iterations properly participate in checkpointing.
void	setMaxConcurrentCheckpoints(int maxConcurrentCheckpoints) Sets the maximum number of checkpoint attempts that may be in progress at the same time.
void	setMinPauseBetweenCheckpoints(long minPauseBetweenCheckpoints) Sets the minimal pause between checkpointing attempts.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MODE

public static final CheckpointingMode DEFAULT_MODE

The default checkpoint mode: exactly once.

DEFAULT_TIMEOUT

public static final long DEFAULT_TIMEOUT

The default timeout of a checkpoint attempt: 10 minutes.

See Also:

Constant Field Values

DEFAULT_MIN_PAUSE_BETWEEN_CHECKPOINTS

public static final long DEFAULT_MIN_PAUSE_BETWEEN_CHECKPOINTS

The default minimum pause to be made between checkpoints: none.

See Also:

Constant Field Values

DEFAULT_MAX_CONCURRENT_CHECKPOINTS

public static final int DEFAULT_MAX_CONCURRENT_CHECKPOINTS

The default limit of concurrently happening checkpoints: one.

See Also:

Constant Field Values

Constructor Detail

CheckpointConfig

public CheckpointConfig()

Method Detail

isCheckpointingEnabled

public boolean isCheckpointingEnabled()

Checks whether checkpointing is enabled.

Returns:

True if checkpointing is enables, false otherwise.

getCheckpointingMode

public CheckpointingMode getCheckpointingMode()

Gets the checkpointing mode (exactly-once vs. at-least-once).

Returns:

The checkpointing mode.

setCheckpointingMode

public void setCheckpointingMode(CheckpointingMode checkpointingMode)

Sets the checkpointing mode (exactly-once vs. at-least-once).

Parameters:

checkpointingMode - The checkpointing mode.

getCheckpointInterval

public long getCheckpointInterval()

Gets the interval in which checkpoints are periodically scheduled.

This setting defines the base interval. Checkpoint triggering may be delayed by the settings getMaxConcurrentCheckpoints() and getMinPauseBetweenCheckpoints().

Returns:

The checkpoint interval, in milliseconds.

setCheckpointInterval

public void setCheckpointInterval(long checkpointInterval)

Sets the interval in which checkpoints are periodically scheduled.

This setting defines the base interval. Checkpoint triggering may be delayed by the settings setMaxConcurrentCheckpoints(int) and setMinPauseBetweenCheckpoints(long).

Parameters:

checkpointInterval - The checkpoint interval, in milliseconds.

getCheckpointTimeout

public long getCheckpointTimeout()

Gets the maximum time that a checkpoint may take before being discarded.

Returns:

The checkpoint timeout, in milliseconds.

setCheckpointTimeout

public void setCheckpointTimeout(long checkpointTimeout)

Sets the maximum time that a checkpoint may take before being discarded.

Parameters:

checkpointTimeout - The checkpoint timeout, in milliseconds.

getMinPauseBetweenCheckpoints

public long getMinPauseBetweenCheckpoints()

Gets the minimal pause between checkpointing attempts. This setting defines how soon the checkpoint coordinator may trigger another checkpoint after it becomes possible to trigger another checkpoint with respect to the maximum number of concurrent checkpoints (see getMaxConcurrentCheckpoints()).

Returns:

The minimal pause before the next checkpoint is triggered.

setMinPauseBetweenCheckpoints

public void setMinPauseBetweenCheckpoints(long minPauseBetweenCheckpoints)

Sets the minimal pause between checkpointing attempts. This setting defines how soon the checkpoint coordinator may trigger another checkpoint after it becomes possible to trigger another checkpoint with respect to the maximum number of concurrent checkpoints (see setMaxConcurrentCheckpoints(int)).

If the maximum number of concurrent checkpoints is set to one, this setting makes effectively sure that a minimum amount of time passes where no checkpoint is in progress at all.

Parameters:

minPauseBetweenCheckpoints - The minimal pause before the next checkpoint is triggered.

getMaxConcurrentCheckpoints

public int getMaxConcurrentCheckpoints()

Gets the maximum number of checkpoint attempts that may be in progress at the same time. If this value is n, then no checkpoints will be triggered while n checkpoint attempts are currently in flight. For the next checkpoint to be triggered, one checkpoint attempt would need to finish or expire.

Returns:

The maximum number of concurrent checkpoint attempts.

setMaxConcurrentCheckpoints

public void setMaxConcurrentCheckpoints(int maxConcurrentCheckpoints)

Sets the maximum number of checkpoint attempts that may be in progress at the same time. If this value is n, then no checkpoints will be triggered while n checkpoint attempts are currently in flight. For the next checkpoint to be triggered, one checkpoint attempt would need to finish or expire.

Parameters:

maxConcurrentCheckpoints - The maximum number of concurrent checkpoint attempts.

isForceCheckpointing

@Deprecated
@PublicEvolving
public boolean isForceCheckpointing()

Deprecated. This will be removed once iterations properly participate in checkpointing.

Checks whether checkpointing is forced, despite currently non-checkpointable iteration feedback.

Returns:

True, if checkpointing is forced, false otherwise.

setForceCheckpointing

@Deprecated
@PublicEvolving
public void setForceCheckpointing(boolean forceCheckpointing)

Deprecated. This will be removed once iterations properly participate in checkpointing.

Checks whether checkpointing is forced, despite currently non-checkpointable iteration feedback.

Parameters:

forceCheckpointing - The flag to force checkpointing.

enableExternalizedCheckpoints

@PublicEvolving
public void enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup cleanupMode)

Enables checkpoints to be persisted externally.

Externalized checkpoints write their meta data out to persistent storage and are not automatically cleaned up when the owning job fails or is suspended (terminating with job status JobStatus.FAILED or JobStatus.SUSPENDED). In this case, you have to manually clean up the checkpoint state, both the meta data and actual program state.

The CheckpointConfig.ExternalizedCheckpointCleanup mode defines how an externalized checkpoint should be cleaned up on job cancellation. If you choose to retain externalized checkpoints on cancellation you have you handle checkpoint clean up manually when you cancel the job as well (terminating with job status JobStatus.CANCELED).

The target directory for externalized checkpoints is configured via ConfigConstants.CHECKPOINTS_DIRECTORY_KEY.

Parameters:

cleanupMode - Externalized checkpoint cleanup behaviour.

isExternalizedCheckpointsEnabled

@PublicEvolving
public boolean isExternalizedCheckpointsEnabled()

Returns whether checkpoints should be persisted externally.

Returns:

true if checkpoints should be externalized.

getExternalizedCheckpointCleanup

@PublicEvolving
public CheckpointConfig.ExternalizedCheckpointCleanup getExternalizedCheckpointCleanup()

Returns the cleanup behaviour for externalized checkpoints.

Returns:

The cleanup behaviour for externalized checkpoints or null if none is configured.