Class MonitoredThreadPoolExecutor

  • All Implemented Interfaces:
    java.util.concurrent.Executor, java.util.concurrent.ExecutorService

    public class MonitoredThreadPoolExecutor
    extends java.util.concurrent.ThreadPoolExecutor
    Thread pool executor based on the Java 5 ThreadPoolExecutor class. Uses a monitoring thread to monitor pool thread behavior to adjust pool size.
    • Nested Class Summary

      • Nested classes/interfaces inherited from class java.util.concurrent.ThreadPoolExecutor

        java.util.concurrent.ThreadPoolExecutor.AbortPolicy, java.util.concurrent.ThreadPoolExecutor.CallerRunsPolicy, java.util.concurrent.ThreadPoolExecutor.DiscardOldestPolicy, java.util.concurrent.ThreadPoolExecutor.DiscardPolicy
    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected static boolean AGGRESSIVE
      If true, be more aggressive when creating threads.
      protected static int BASE_TCNT
      Starting number of threads.
      protected static boolean DEBUG
      Print debug messages
      protected java.util.concurrent.atomic.AtomicInteger idle
      Number of idle threads in the pool.
      protected static long LOSS_THRESHOLD
      Threshold after which a _blocking_ thread is considered stolen.
      protected static long LOSS_THRESHOLD_BUSY
      Threshold after which a _non-blocking_ thread is considered stolen.
      protected static long MONIT_CYCLE
      Min. wait time between monitoring cycles.
      protected static int MONIT_THRESHOLD
      Threshold for activating monitoring.
      protected boolean monitoring
      Flag for monitoring thread activity.
      protected java.util.concurrent.Semaphore monitoringlock
      The lock for the monitoring thread.
      protected java.lang.Thread monitthread
      The monitoring thread.
      protected MonitoredThread[] threads
      The threads in the pool.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected void borrow​(MonitoredThread thread)
      Borrows the thread.
      protected void borrowNoUnpark​(MonitoredThread thread)
      Borrows the thread without unparking.
      protected static MonitoredThread currentThread()
      Gets the current MonitoredThread, for convenience.
      void execute​(java.lang.Runnable command)  
      protected static void releaseLock​(java.util.concurrent.Semaphore lock)
      Releases the semaphore, includes null check.
      • Methods inherited from class java.util.concurrent.ThreadPoolExecutor

        afterExecute, allowCoreThreadTimeOut, allowsCoreThreadTimeOut, awaitTermination, beforeExecute, finalize, getActiveCount, getCompletedTaskCount, getCorePoolSize, getKeepAliveTime, getLargestPoolSize, getMaximumPoolSize, getPoolSize, getQueue, getRejectedExecutionHandler, getTaskCount, getThreadFactory, isShutdown, isTerminated, isTerminating, prestartAllCoreThreads, prestartCoreThread, purge, remove, setCorePoolSize, setKeepAliveTime, setMaximumPoolSize, setRejectedExecutionHandler, setThreadFactory, shutdown, shutdownNow, terminated, toString
      • Methods inherited from class java.util.concurrent.AbstractExecutorService

        invokeAll, invokeAll, invokeAny, invokeAny, newTaskFor, newTaskFor, submit, submit, submit
      • Methods inherited from class java.lang.Object

        clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
    • Field Detail

      • AGGRESSIVE

        protected static final boolean AGGRESSIVE
        If true, be more aggressive when creating threads.
        See Also:
        Constant Field Values
      • MONIT_THRESHOLD

        protected static final int MONIT_THRESHOLD
        Threshold for activating monitoring.
      • BASE_TCNT

        protected static final int BASE_TCNT
        Starting number of threads.
      • MONIT_CYCLE

        protected static final long MONIT_CYCLE
        Min. wait time between monitoring cycles.
        See Also:
        Constant Field Values
      • LOSS_THRESHOLD

        protected static final long LOSS_THRESHOLD
        Threshold after which a _blocking_ thread is considered stolen.
        See Also:
        Constant Field Values
      • LOSS_THRESHOLD_BUSY

        protected static final long LOSS_THRESHOLD_BUSY
        Threshold after which a _non-blocking_ thread is considered stolen.
        See Also:
        Constant Field Values
      • idle

        protected java.util.concurrent.atomic.AtomicInteger idle
        Number of idle threads in the pool.
      • threads

        protected volatile MonitoredThread[] threads
        The threads in the pool.
      • monitoringlock

        protected volatile java.util.concurrent.Semaphore monitoringlock
        The lock for the monitoring thread.
      • monitthread

        protected java.lang.Thread monitthread
        The monitoring thread.
      • monitoring

        protected boolean monitoring
        Flag for monitoring thread activity.
    • Constructor Detail

      • MonitoredThreadPoolExecutor

        public MonitoredThreadPoolExecutor()
    • Method Detail

      • execute

        public void execute​(java.lang.Runnable command)
        Specified by:
        execute in interface java.util.concurrent.Executor
        Overrides:
        execute in class java.util.concurrent.ThreadPoolExecutor
      • borrow

        protected void borrow​(MonitoredThread thread)
        Borrows the thread.
        Parameters:
        thread - Thre thread being borrowed.
      • borrowNoUnpark

        protected void borrowNoUnpark​(MonitoredThread thread)
        Borrows the thread without unparking.
        Parameters:
        thread - Thre thread being borrowed.
      • releaseLock

        protected static final void releaseLock​(java.util.concurrent.Semaphore lock)
        Releases the semaphore, includes null check.
        Parameters:
        lock - The lock.
      • currentThread

        protected static final MonitoredThread currentThread()
        Gets the current MonitoredThread, for convenience.
        Returns:
        Current MonitoredThread.