org.apache.flink.runtime.checkpoint

Class SubtaskState

java.lang.Object

org.apache.flink.runtime.checkpoint.SubtaskState

All Implemented Interfaces:

Serializable, CompositeStateHandle, StateObject

public class SubtaskState
extends Object
implements CompositeStateHandle

Container for the chained state of one parallel subtask of an operator/task. This is part of the TaskState.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
SubtaskState(ChainedStateHandle<OperatorStateHandle> managedOperatorState, ChainedStateHandle<OperatorStateHandle> rawOperatorState, KeyedStateHandle managedKeyedState, KeyedStateHandle rawKeyedState)

Method Summary

Modifier and Type	Method and Description
void	discardState() Discards the state referred to and solemnly owned by this handle, to free up resources in the persistent storage.
boolean	equals(Object o)
KeyedStateHandle	getManagedKeyedState()
ChainedStateHandle<OperatorStateHandle>	getManagedOperatorState()
KeyedStateHandle	getRawKeyedState()
ChainedStateHandle<OperatorStateHandle>	getRawOperatorState()
long	getStateSize() Returns the size of the state in bytes.
int	hashCode()
void	registerSharedStates(SharedStateRegistry sharedStateRegistry) Register both newly created and already referenced shared states in the given SharedStateRegistry.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SubtaskState

public SubtaskState(ChainedStateHandle<OperatorStateHandle> managedOperatorState,
                    ChainedStateHandle<OperatorStateHandle> rawOperatorState,
                    KeyedStateHandle managedKeyedState,
                    KeyedStateHandle rawKeyedState)

Method Detail

getManagedOperatorState

public ChainedStateHandle<OperatorStateHandle> getManagedOperatorState()

getRawOperatorState

public ChainedStateHandle<OperatorStateHandle> getRawOperatorState()

getManagedKeyedState

public KeyedStateHandle getManagedKeyedState()

getRawKeyedState

public KeyedStateHandle getRawKeyedState()

discardState

public void discardState()

Description copied from interface: StateObject

Discards the state referred to and solemnly owned by this handle, to free up resources in the persistent storage. This method is called when the state represented by this object will not be used any more.

Specified by:

discardState in interface StateObject

registerSharedStates

public void registerSharedStates(SharedStateRegistry sharedStateRegistry)

Description copied from interface: CompositeStateHandle

Register both newly created and already referenced shared states in the given SharedStateRegistry. This method is called when the checkpoint successfully completes or is recovered from failures.

After this is completed, newly created shared state is considered as published is no longer owned by this handle. This means that it should no longer be deleted as part of calls to StateObject.discardState(). Instead, StateObject.discardState() will trigger an unregistration from the registry.

Specified by:

registerSharedStates in interface CompositeStateHandle

Parameters:

sharedStateRegistry - The registry where shared states are registered.

getStateSize

public long getStateSize()

Description copied from interface: StateObject

Returns the size of the state in bytes. If the size is not known, this method should return 0.

The values produced by this method are only used for informational purposes and for metrics/monitoring. If this method returns wrong values, the checkpoints and recovery will still behave correctly. However, efficiency may be impacted (wrong space pre-allocation) and functionality that depends on metrics (like monitoring) will be impacted.

Note for implementors: This method should not perform any I/O operations while obtaining the state size (hence it does not declare throwing an IOException). Instead, the state size should be stored in the state object, or should be computable from the state stored in this object. The reason is that this method is called frequently by several parts of the checkpointing and issuing I/O requests from this method accumulates a heavy I/O load on the storage system at higher scale.

Specified by:

getStateSize in interface StateObject

Returns:

Size of the state in bytes.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object