org.apache.hadoop.hbase.procedure2

Class SimpleProcedureScheduler

java.lang.Object

org.apache.hadoop.hbase.procedure2.AbstractProcedureScheduler

org.apache.hadoop.hbase.procedure2.SimpleProcedureScheduler

All Implemented Interfaces:

ProcedureScheduler

@InterfaceAudience.Private
 @InterfaceStability.Evolving
public class SimpleProcedureScheduler
extends AbstractProcedureScheduler

Simple scheduler for procedures

Field Summary

Fields

Modifier and Type	Field and Description
private ProcedureDeque	runnables

Constructor Summary

Constructors

Constructor and Description
SimpleProcedureScheduler()

Method Summary

Modifier and Type	Method and Description
void	clear() Clear current state of scheduler such that it is equivalent to newly created scheduler.
void	completionCleanup(Procedure proc) The procedure in execution completed.
protected Procedure	dequeue() Fetch one Procedure from the queue NOTE: this method is called with the sched lock held.
protected void	enqueue(Procedure procedure, boolean addFront) Add the procedure to the queue.
LockedResource	getLockResource(LockedResourceType resourceType, String resourceName)
List<LockedResource>	getLocks() List lock queues.
boolean	queueHasRunnables() Returns true if there are procedures available to process.
int	queueSize() Returns the number of elements in this queue.
void	yield(Procedure proc) The procedure can't run at the moment.

Methods inherited from class org.apache.hadoop.hbase.procedure2.AbstractProcedureScheduler

addBack, addBack, addFront, addFront, addFront, getNullPollCalls, getPollCalls, hasRunnables, poll, poll, poll, push, schedLock, schedUnlock, signalAll, size, start, stop, waitProcedure, wakeEvents, wakePollIfNeeded, wakeProcedure, wakeWaitingProcedures

Methods inherited from class java.lang.Object

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

Field Detail

runnables

private final ProcedureDeque runnables

Constructor Detail

SimpleProcedureScheduler

public SimpleProcedureScheduler()

Method Detail

enqueue

protected void enqueue(Procedure procedure,
                       boolean addFront)

Description copied from class: AbstractProcedureScheduler

Add the procedure to the queue. NOTE: this method is called with the sched lock held.

Specified by:

enqueue in class AbstractProcedureScheduler

Parameters:

procedure - the Procedure to add

addFront - true if the item should be added to the front of the queue

dequeue

protected Procedure dequeue()

Description copied from class: AbstractProcedureScheduler

Fetch one Procedure from the queue NOTE: this method is called with the sched lock held.

Specified by:

dequeue in class AbstractProcedureScheduler

Returns:

the Procedure to execute, or null if nothing is available.

clear

public void clear()

Description copied from interface: ProcedureScheduler

Clear current state of scheduler such that it is equivalent to newly created scheduler. Used for testing failure and recovery. To emulate server crash/restart, ProcedureExecutor resets its own state and calls clear() on scheduler.

yield

public void yield(Procedure proc)

Description copied from interface: ProcedureScheduler

The procedure can't run at the moment. add it back to the queue, giving priority to someone else.

Parameters:

proc - the Procedure to add back to the list

queueHasRunnables

public boolean queueHasRunnables()

Description copied from class: AbstractProcedureScheduler

Returns true if there are procedures available to process. NOTE: this method is called with the sched lock held.

Specified by:

queueHasRunnables in class AbstractProcedureScheduler

Returns:

true if there are procedures available to process, otherwise false.

queueSize

public int queueSize()

Description copied from class: AbstractProcedureScheduler

Returns the number of elements in this queue. NOTE: this method is called with the sched lock held.

Specified by:

queueSize in class AbstractProcedureScheduler

Returns:

the number of elements in this queue.

completionCleanup

public void completionCleanup(Procedure proc)

Description copied from interface: ProcedureScheduler

The procedure in execution completed. This can be implemented to perform cleanups.

Parameters:

proc - the Procedure that completed the execution.

getLocks

public List<LockedResource> getLocks()

Description copied from interface: ProcedureScheduler

List lock queues.

Returns:

the locks

getLockResource

public LockedResource getLockResource(LockedResourceType resourceType,
                                      String resourceName)

Returns:

LockedResource for resource of specified type & name. null if resource is not locked.