CVS update: JGroups/src/org/jgroups/util HashedTimingWheel.java

  User: belaban 
  Date: 10/08/04 16:03:32

  Modified:    src/org/jgroups/util HashedTimingWheel.java
  Log:
  ns
  
  Revision  Changes    Path
  1.2       +22 -11    JGroups/src/org/jgroups/util/HashedTimingWheel.java
  
  Index: HashedTimingWheel.java
  ===================================================================
  RCS file: /cvsroot/javagroups/JGroups/src/org/jgroups/util/HashedTimingWheel.java,v
  retrieving revision 1.1
  retrieving revision 1.2
  diff -u -r1.1 -r1.2
  --- HashedTimingWheel.java	4 Aug 2010 14:08:19 -0000	1.1
  +++ HashedTimingWheel.java	4 Aug 2010 16:03:32 -0000	1.2
  @@ -21,7 +21,7 @@
    * [1] http://www.cse.wustl.edu/~cdgill/courses/cs6874/TimingWheels.ppt
    *
    * @author Bela Ban
  - * @version $Id: HashedTimingWheel.java,v 1.1 2010/08/04 14:08:19 belaban Exp $
  + * @version $Id: HashedTimingWheel.java,v 1.2 2010/08/04 16:03:32 belaban Exp $
    */
   @Experimental @Unsupported
   public class HashedTimingWheel implements TimeScheduler, Runnable  {
  @@ -39,11 +39,13 @@
   
       protected ThreadFactory timer_thread_factory=null;
   
  -    protected static final int WHEEL_SIZE=256;   // number of ticks on the timing wheel
  +    protected static final int WHEEL_SIZE=200;   // number of ticks on the timing wheel
   
  -    protected static final long TICK_TIME=100L;  // number of milliseconds a tick has
  +    protected static final long TICK_TIME=50L;  // number of milliseconds a tick has
   
  -    protected final List<MyTask>[] wheel=new List[WHEEL_SIZE];
  +    protected static final long ROTATION_TIME=WHEEL_SIZE * TICK_TIME; // time for 1 lap
  +
  +    protected final List<MyTask>[] wheel;
   
       protected int wheel_position=0; // current position of the wheel, run() advances it by one (every TICK_TIME ms)
   
  @@ -51,7 +53,9 @@
       /**
        * Create a scheduler that executes tasks in dynamically adjustable intervals
        */
  +    @SuppressWarnings("unchecked")
       public HashedTimingWheel() {
  +        wheel=new List[WHEEL_SIZE];
           pool=new ThreadManagerThreadPoolExecutor(4, 10,
                                                    5000, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(5000),
                                                    Executors.defaultThreadFactory(), new ThreadPoolExecutor.CallerRunsPolicy());
  @@ -59,7 +63,9 @@
       }
   
   
  +    @SuppressWarnings("unchecked")
       public HashedTimingWheel(ThreadFactory factory, int min_threads, int max_threads, long keep_alive_time, int max_queue_size) {
  +        wheel=new List[WHEEL_SIZE];
           timer_thread_factory=factory;
           pool=new ThreadManagerThreadPoolExecutor(min_threads, max_threads,keep_alive_time, TimeUnit.MILLISECONDS,
                                                    new LinkedBlockingQueue<Runnable>(max_queue_size),
  @@ -67,7 +73,9 @@
           init();
       }
   
  +    @SuppressWarnings("unchecked")
       public HashedTimingWheel(int corePoolSize) {
  +        wheel=(List<MyTask>[])new List[WHEEL_SIZE];
           pool=new ThreadManagerThreadPoolExecutor(corePoolSize, corePoolSize * 2,
                                                    5000, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>(5000),
                                                    Executors.defaultThreadFactory(), new ThreadPoolExecutor.CallerRunsPolicy());
  @@ -154,14 +162,13 @@
   
           MyTask retval=null;
   
  -        long time=System.currentTimeMillis() + unit.convert(delay, TimeUnit.MILLISECONDS); // execution time
  +        long time=unit.convert(delay, TimeUnit.MILLISECONDS); // execution time
   
           lock.lock();
           try {
  -            int num_ticks=(int)((time % (WHEEL_SIZE * TICK_TIME)) / TICK_TIME);
  +            int num_ticks=(int)Math.max(1, ((time % ROTATION_TIME) / TICK_TIME));
               int position=(wheel_position + num_ticks) % WHEEL_SIZE;
  -            int rounds=(int)(time / (WHEEL_SIZE * TICK_TIME));
  -
  +            int rounds=(int)(time / ROTATION_TIME);
               List<MyTask> list=wheel[position];
               retval=new MyTask(work, rounds);
               list.add(retval);
  @@ -265,8 +272,6 @@
           }
           catch(InterruptedException e) {
           }
  -
  -
       }
   
   
  @@ -276,10 +281,16 @@
   
   
       public void run() {
  +        final long base_time=System.currentTimeMillis();
  +        long next_time, sleep_time;
  +        long cnt=0;
  +
           while(running) {
               try {
                   _run();
  -                Util.sleep(TICK_TIME);
  +                next_time=base_time + (++cnt * TICK_TIME);
  +                sleep_time=Math.max(0, next_time - System.currentTimeMillis());
  +                Util.sleep(sleep_time);
               }
               catch(Throwable t) {
                   log.error("failed executing tasks(s)", t);
  
  
  

------------------------------------------------------------------------------
The Palm PDK Hot Apps Program offers developers who use the
Plug-In Development Kit to bring their C/C++ apps to Palm for a share
of $1 Million in cash or HP Products. Visit us here for more details:
http://p.sf.net/sfu/dev2dev-palm