test/loops/CachedThreadPoolLoops.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 */

//import jsr166y.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;

public class CachedThreadPoolLoops {
    static final int NCPUS = Runtime.getRuntime().availableProcessors();
    static final AtomicInteger remaining = new AtomicInteger();
    static final int maxIters = 1000000;

    public static void main(String[] args) throws Exception {
        int maxThreads = NCPUS * 3 / 2; // 100;
        if (args.length > 0)
            maxThreads = Integer.parseInt(args[0]);

        System.out.print("Warmup:");
        for (int j = 0; j < 1; ++j) {
            for (int k = 1, 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();

        for (int k = 1, 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 {
        Thread.sleep(100); // System.gc();
        if (print) System.out.print("LinkedTransferQueue      ");
        oneRun(new LinkedTransferQueue<Runnable>(), nThreads, iters, print);

        Thread.sleep(100); // System.gc();
        if (print) System.out.print("LinkedBlockingQueue      ");
        oneRun(new LinkedBlockingQueue<Runnable>(), nThreads, iters, print);

        Thread.sleep(100); // System.gc();
        if (print) System.out.print("SynchronousQueue         ");
        oneRun(new SynchronousQueue<Runnable>(false), nThreads, iters, print);

        Thread.sleep(100); // System.gc();
        if (print) System.out.print("SynchronousQueue(fair)   ");
        oneRun(new SynchronousQueue<Runnable>(true), nThreads, iters, print);

        Thread.sleep(100); // System.gc();
        if (print) System.out.print("LinkedTransferQueue(xfer)");
        oneRun(new LTQasSQ<Runnable>(), nThreads, iters, print);

        Thread.sleep(100); // System.gc();
        if (print) System.out.print("LinkedTransferQueue(half)");
        oneRun(new HalfSyncLTQ<Runnable>(), nThreads, iters, print);

        Thread.sleep(100); // System.gc();
        if (print) System.out.print("ArrayBlockingQueue(256) ");
        oneRun(new ArrayBlockingQueue<Runnable>(256), 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();
    }

    static final class LTQasSQ<T> extends LinkedTransferQueue<T> {
        LTQasSQ() { super(); }
        public void put(T x) {
            try { super.transfer(x);
            } catch (InterruptedException ex) { throw new Error(); }
        }
    }

    static final class HalfSyncLTQ<T> extends LinkedTransferQueue<T> {
        int calls;
        HalfSyncLTQ() { super(); }
        public void put(T x) {
            if ((++calls & 1) == 0)
                super.put(x);
            else {
                try { super.transfer(x);
                } catch (InterruptedException ex) {
                    throw new Error();
                }
            }
        }
    }

}
Revision:	1.8
Committed:	Thu Dec 18 18:13:06 2014 UTC (9 years, 5 months ago) by jsr166
Branch:	MAIN
Changes since 1.7:	+2 -4 lines
Log Message:	move k = 1 into loop initializer
#	User	Rev	Content
1	dl	1.1	/*
2			* Written by Doug Lea with assistance from members of JCP JSR-166
3	dl	1.3	* Expert Group and released to the public domain, as explained at
4	jsr166	1.6	* http://creativecommons.org/publicdomain/zero/1.0/
5	dl	1.1	*/
6
7	dl	1.4	//import jsr166y.*;
8	dl	1.1	import java.util.concurrent.*;
9			import java.util.concurrent.atomic.*;
10
11			public class CachedThreadPoolLoops {
12	dl	1.4	static final int NCPUS = Runtime.getRuntime().availableProcessors();
13	dl	1.1	static final AtomicInteger remaining = new AtomicInteger();
14			static final int maxIters = 1000000;
15
16			public static void main(String[] args) throws Exception {
17	dl	1.4	int maxThreads = NCPUS * 3 / 2; // 100;
18	jsr166	1.5	if (args.length > 0)
19	dl	1.1	maxThreads = Integer.parseInt(args[0]);
20	dl	1.2
21			System.out.print("Warmup:");
22	dl	1.4	for (int j = 0; j < 1; ++j) {
23	jsr166	1.8	for (int k = 1, i = 1; i <= maxThreads;) {
24	dl	1.2	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	jsr166	1.5	}
31			else
32	dl	1.2	i = k;
33			}
34			}
35			System.out.println();
36
37	jsr166	1.8	for (int k = 1, i = 1; i <= maxThreads;) {
38	dl	1.1	System.out.println("Threads:" + i);
39	dl	1.2	oneTest(i, maxIters, true);
40	dl	1.1	Thread.sleep(100);
41			if (i == k) {
42			k = i << 1;
43			i = i + (i >>> 1);
44	jsr166	1.5	}
45			else
46	dl	1.1	i = k;
47			}
48	jsr166	1.7	}
49	dl	1.1
50	dl	1.2	static void oneTest(int nThreads, int iters, boolean print) throws Exception {
51	dl	1.4	Thread.sleep(100); // System.gc();
52			if (print) System.out.print("LinkedTransferQueue ");
53			oneRun(new LinkedTransferQueue<Runnable>(), nThreads, iters, print);
54
55			Thread.sleep(100); // System.gc();
56			if (print) System.out.print("LinkedBlockingQueue ");
57			oneRun(new LinkedBlockingQueue<Runnable>(), nThreads, iters, print);
58
59			Thread.sleep(100); // System.gc();
60			if (print) System.out.print("SynchronousQueue ");
61	dl	1.2	oneRun(new SynchronousQueue<Runnable>(false), nThreads, iters, print);
62	dl	1.4
63			Thread.sleep(100); // System.gc();
64			if (print) System.out.print("SynchronousQueue(fair) ");
65	dl	1.2	oneRun(new SynchronousQueue<Runnable>(true), nThreads, iters, print);
66	dl	1.4
67			Thread.sleep(100); // System.gc();
68			if (print) System.out.print("LinkedTransferQueue(xfer)");
69			oneRun(new LTQasSQ<Runnable>(), nThreads, iters, print);
70
71			Thread.sleep(100); // System.gc();
72			if (print) System.out.print("LinkedTransferQueue(half)");
73			oneRun(new HalfSyncLTQ<Runnable>(), nThreads, iters, print);
74
75			Thread.sleep(100); // System.gc();
76			if (print) System.out.print("ArrayBlockingQueue(256) ");
77			oneRun(new ArrayBlockingQueue<Runnable>(256), nThreads, iters, print);
78
79	dl	1.1	}
80
81			static final class Task implements Runnable {
82			final ThreadPoolExecutor pool;
83			final CountDownLatch done;
84	jsr166	1.5	Task(ThreadPoolExecutor p, CountDownLatch d) {
85			pool = p;
86	dl	1.1	done = d;
87			}
88			public void run() {
89			done.countDown();
90			remaining.incrementAndGet();
91			int n;
92			while (!Thread.interrupted() &&
93	jsr166	1.5	(n = remaining.get()) > 0 &&
94	dl	1.1	done.getCount() > 0) {
95			if (remaining.compareAndSet(n, n-1)) {
96			try {
97			pool.execute(this);
98			}
99			catch (RuntimeException ex) {
100			System.out.print("*");
101			while (done.getCount() > 0) done.countDown();
102			return;
103			}
104			}
105			}
106			}
107			}
108	jsr166	1.5
109	dl	1.2	static void oneRun(BlockingQueue<Runnable> q, int nThreads, int iters, boolean print) throws Exception {
110	jsr166	1.5
111			ThreadPoolExecutor pool =
112	dl	1.1	new ThreadPoolExecutor(nThreads+1, Integer.MAX_VALUE,
113			1L, TimeUnit.SECONDS, q);
114
115	dl	1.2	CountDownLatch done = new CountDownLatch(iters);
116	dl	1.1	remaining.set(nThreads-1);
117			pool.prestartAllCoreThreads();
118			Task t = new Task(pool, done);
119			long start = System.nanoTime();
120			pool.execute(t);
121			done.await();
122			long time = System.nanoTime() - start;
123	dl	1.2	if (print)
124			System.out.println("\t: " + LoopHelpers.rightJustify(time / iters) + " ns per task");
125			q.clear();
126			Thread.sleep(100);
127			pool.shutdown();
128			Thread.sleep(100);
129	dl	1.1	pool.shutdownNow();
130			}
131
132	dl	1.4	static final class LTQasSQ<T> extends LinkedTransferQueue<T> {
133			LTQasSQ() { super(); }
134			public void put(T x) {
135	jsr166	1.5	try { super.transfer(x);
136	dl	1.4	} catch (InterruptedException ex) { throw new Error(); }
137			}
138			}
139
140			static final class HalfSyncLTQ<T> extends LinkedTransferQueue<T> {
141			int calls;
142			HalfSyncLTQ() { super(); }
143			public void put(T x) {
144			if ((++calls & 1) == 0)
145			super.put(x);
146			else {
147	jsr166	1.5	try { super.transfer(x);
148			} catch (InterruptedException ex) {
149			throw new Error();
150	dl	1.4	}
151			}
152			}
153			}
154
155	dl	1.1	}