test/loops/CachedThreadPoolLoops.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain. Use, modify, and
 * redistribute this code in any way without acknowledgement.
 */

import java.util.concurrent.*;
import java.util.concurrent.atomic.*;

public class CachedThreadPoolLoops {
    static final AtomicInteger remaining = new AtomicInteger();
    static final int maxIters = 1000000;

    public static void main(String[] args) throws Exception {
        int maxThreads = 100;

        if (args.length > 0) 
            maxThreads = Integer.parseInt(args[0]);

        System.out.print("Warmup:");
        for (int j = 0; j < 2; ++j) {
            int k = 1;
            for (int i = 1; i <= maxThreads;) {
                System.out.print(" " + i);
                oneTest(i, 10000, false);
                Thread.sleep(100);
                if (i == k) {
                    k = i << 1;
                    i = i + (i >>> 1);
                } 
                else 
                    i = k;
            }
        }
        System.out.println();

        int k = 1;
        for (int i = 1; i <= maxThreads;) {
            System.out.println("Threads:" + i);
            oneTest(i, maxIters, true);
            Thread.sleep(100);
            if (i == k) {
                k = i << 1;
                i = i + (i >>> 1);
            } 
            else 
                i = k;
        }
   }

    static void oneTest(int nThreads, int iters, boolean print) throws Exception {
        if (print) System.out.print("SynchronousQueue        ");
        oneRun(new SynchronousQueue<Runnable>(false), nThreads, iters, print);
        if (print) System.out.print("SynchronousQueue(fair)  ");
        oneRun(new SynchronousQueue<Runnable>(true), nThreads, iters, print);
    }

    static final class Task implements Runnable {
        final ThreadPoolExecutor pool;
        final CountDownLatch done;
        Task(ThreadPoolExecutor p, CountDownLatch d) { 
            pool = p; 
            done = d;
        }
        public void run() {
            done.countDown();
            remaining.incrementAndGet();
            int n;
            while (!Thread.interrupted() &&
                   (n = remaining.get()) > 0 && 
                   done.getCount() > 0) {
                if (remaining.compareAndSet(n, n-1)) {
                    try {
                        pool.execute(this);
                    }
                    catch (RuntimeException ex) {
                        System.out.print("*");
                        while (done.getCount() > 0) done.countDown();
                        return;
                    }
                }
            }
        }
    }
    
    static void oneRun(BlockingQueue<Runnable> q, int nThreads, int iters, boolean print) throws Exception {
       
        ThreadPoolExecutor pool = 
            new ThreadPoolExecutor(nThreads+1, Integer.MAX_VALUE,
                                   1L, TimeUnit.SECONDS, q);

        CountDownLatch done = new CountDownLatch(iters);
        remaining.set(nThreads-1);
        pool.prestartAllCoreThreads();
        Task t = new Task(pool, done);
        long start = System.nanoTime();
        pool.execute(t);
        done.await();
        long time = System.nanoTime() - start;
        if (print)
            System.out.println("\t: " + LoopHelpers.rightJustify(time / iters) + " ns per task");
        q.clear();
        Thread.sleep(100);
        pool.shutdown();
        Thread.sleep(100);
        pool.shutdownNow();
    }

}
Revision:	1.2
Committed:	Sun Aug 7 19:25:55 2005 UTC (18 years, 9 months ago) by dl
Branch:	MAIN
Changes since 1.1:	+32 -10 lines
Log Message:	Add exchanger performance tests; update others
#	Content
1	/*
2	* Written by Doug Lea with assistance from members of JCP JSR-166
3	* Expert Group and released to the public domain. Use, modify, and
4	* redistribute this code in any way without acknowledgement.
5	*/
6
7	import java.util.concurrent.*;
8	import java.util.concurrent.atomic.*;
9
10	public class CachedThreadPoolLoops {
11	static final AtomicInteger remaining = new AtomicInteger();
12	static final int maxIters = 1000000;
13
14	public static void main(String[] args) throws Exception {
15	int maxThreads = 100;
16
17	if (args.length > 0)
18	maxThreads = Integer.parseInt(args[0]);
19
20	System.out.print("Warmup:");
21	for (int j = 0; j < 2; ++j) {
22	int k = 1;
23	for (int i = 1; i <= maxThreads;) {
24	System.out.print(" " + i);
25	oneTest(i, 10000, false);
26	Thread.sleep(100);
27	if (i == k) {
28	k = i << 1;
29	i = i + (i >>> 1);
30	}
31	else
32	i = k;
33	}
34	}
35	System.out.println();
36
37	int k = 1;
38	for (int i = 1; i <= maxThreads;) {
39	System.out.println("Threads:" + i);
40	oneTest(i, maxIters, true);
41	Thread.sleep(100);
42	if (i == k) {
43	k = i << 1;
44	i = i + (i >>> 1);
45	}
46	else
47	i = k;
48	}
49	}
50
51	static void oneTest(int nThreads, int iters, boolean print) throws Exception {
52	if (print) System.out.print("SynchronousQueue ");
53	oneRun(new SynchronousQueue<Runnable>(false), nThreads, iters, print);
54	if (print) System.out.print("SynchronousQueue(fair) ");
55	oneRun(new SynchronousQueue<Runnable>(true), nThreads, iters, print);
56	}
57
58	static final class Task implements Runnable {
59	final ThreadPoolExecutor pool;
60	final CountDownLatch done;
61	Task(ThreadPoolExecutor p, CountDownLatch d) {
62	pool = p;
63	done = d;
64	}
65	public void run() {
66	done.countDown();
67	remaining.incrementAndGet();
68	int n;
69	while (!Thread.interrupted() &&
70	(n = remaining.get()) > 0 &&
71	done.getCount() > 0) {
72	if (remaining.compareAndSet(n, n-1)) {
73	try {
74	pool.execute(this);
75	}
76	catch (RuntimeException ex) {
77	System.out.print("*");
78	while (done.getCount() > 0) done.countDown();
79	return;
80	}
81	}
82	}
83	}
84	}
85
86	static void oneRun(BlockingQueue<Runnable> q, int nThreads, int iters, boolean print) throws Exception {
87
88	ThreadPoolExecutor pool =
89	new ThreadPoolExecutor(nThreads+1, Integer.MAX_VALUE,
90	1L, TimeUnit.SECONDS, q);
91
92	CountDownLatch done = new CountDownLatch(iters);
93	remaining.set(nThreads-1);
94	pool.prestartAllCoreThreads();
95	Task t = new Task(pool, done);
96	long start = System.nanoTime();
97	pool.execute(t);
98	done.await();
99	long time = System.nanoTime() - start;
100	if (print)
101	System.out.println("\t: " + LoopHelpers.rightJustify(time / iters) + " ns per task");
102	q.clear();
103	Thread.sleep(100);
104	pool.shutdown();
105	Thread.sleep(100);
106	pool.shutdownNow();
107	}
108
109	}