org.teiid.dqp.internal.process

Class ThreadReuseExecutor

java.lang.Object

org.teiid.dqp.internal.process.ThreadReuseExecutor

All Implemented Interfaces:

Executor, TeiidExecutor

public class ThreadReuseExecutor
extends Object
implements TeiidExecutor

An Executor that:

1. minimizes thread creation
2. allows for proper timeout of idle threads
3. allows for queuing

A non-fifo (lifo) SynchronousQueue based ThreadPoolExecutor satisfies 1 and 2, but not 3. A bounded or unbound queue based ThreadPoolExecutor allows for 3, but will tend to create up to the maximum number of threads and makes no guarantee on thread scheduling.
So the approach here is to use a virtual thread pool off of a SynchronousQueue backed ThreadPoolExecutor.
There is also only a single master scheduling thread with actual executions deferred. TODO: there is a race condition between retiring threads and adding work, which may create extra threads. That is a flaw with attempting to reuse, rather than create threads. TODO: bounded queuing - we never bothered bounding in the past with our worker pools, but reasonable defaults would be a good idea. TODO: a ForkJoinPool is a simple replacement, but we'd loose the prioritization queue.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ThreadReuseExecutor.PrioritizedRunnable
static class	ThreadReuseExecutor.RunnableWrapper

Constructor Summary

Constructors

Constructor and Description
ThreadReuseExecutor(String name, int maximumPoolSize)

Method Summary

Modifier and Type	Method and Description
boolean	awaitTermination(long timeout, TimeUnit unit)
void	execute(Runnable command)
int	getActiveCount()
long	getCompletedCount()
int	getLargestPoolSize()
int	getQueued()
WorkerPoolStatisticsMetadata	getStats()
long	getSubmittedCount()
boolean	isTerminated()
protected void	logWaitMessage(long warnTime, int maximumPoolSize, String poolName, int highestQueueSize)
void	shutdown()
List<Runnable>	shutdownNow()

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadReuseExecutor

public ThreadReuseExecutor(String name,
                           int maximumPoolSize)

Method Detail

execute

public void execute(Runnable command)

Specified by:

execute in interface Executor

Specified by:

execute in interface TeiidExecutor

logWaitMessage

protected void logWaitMessage(long warnTime,
                              int maximumPoolSize,
                              String poolName,
                              int highestQueueSize)

getActiveCount

public int getActiveCount()

Specified by:

getActiveCount in interface TeiidExecutor

getSubmittedCount

public long getSubmittedCount()

getCompletedCount

public long getCompletedCount()

isTerminated

public boolean isTerminated()

shutdown

public void shutdown()

getLargestPoolSize

public int getLargestPoolSize()

getQueued

public int getQueued()

Specified by:

getQueued in interface TeiidExecutor

getStats

public WorkerPoolStatisticsMetadata getStats()

Specified by:

getStats in interface TeiidExecutor

shutdownNow

public List<Runnable> shutdownNow()

Specified by:

shutdownNow in interface TeiidExecutor

awaitTermination

public boolean awaitTermination(long timeout,
                                TimeUnit unit)
                         throws InterruptedException

Specified by:

awaitTermination in interface TeiidExecutor

Throws:

InterruptedException