test/loops/LongAdderLoops.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 java.util.concurrent.atomic.LongAdder;
import java.util.concurrent.Executors;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Phaser;

public class LongAdderLoops {
    public static void main(String[] args) {
        final int NCPU = Runtime.getRuntime().availableProcessors();
        int minThreads = 1;
        int maxThreads = 2 * NCPU;
        long iters = 300_000_000L;
        nextArg: for (String arg : args) {
            String[] fields = arg.split("=");
            if (fields.length == 2) {
                String prop = fields[0], val = fields[1];
                switch (prop) {
                case "threads":
                    minThreads = maxThreads = Integer.valueOf(val);
                    continue nextArg;
                case "minThreads":
                    minThreads = Integer.valueOf(val);
                    continue nextArg;
                case "maxThreads":
                    maxThreads = Integer.valueOf(val);
                    continue nextArg;
                case "iters":
                    iters = Long.valueOf(val);
                    continue nextArg;
                }
            }
            throw new Error("Usage: LongAdderLoops minThreads=n maxThreads=n threads=n iters=n");
        }

        final ExecutorService pool = Executors.newCachedThreadPool();
        for (int i = minThreads; i <= maxThreads; i += (i+1) >>> 1)
            adderTest(pool, i, iters);
        pool.shutdown();
    }

    static void adderTest(ExecutorService pool, int nthreads, long iters) {
        System.out.print("LongAdder  ");
        Phaser phaser = new Phaser(nthreads + 1);
        LongAdder a = new LongAdder();
        for (int i = 0; i < nthreads; ++i)
            pool.execute(new AdderTask(a, phaser, iters));
        report(nthreads, iters, timeTasks(phaser), a.sum());
    }

    static void report(int nthreads, long iters, long time, long sum) {
        long total = (long)nthreads * iters;
        if (sum != total)
            throw new Error(sum + " != " + total);
        double secs = (double)time / (1000L * 1000 * 1000);
        long rate = total * (1000L) / time;
        System.out.printf("threads:%3d  Time: %7.3fsec  Iters per microsec: %4d\n",
                          nthreads, secs, rate);
    }

    static long timeTasks(Phaser phaser) {
        phaser.arriveAndAwaitAdvance();
        long start = System.nanoTime();
        phaser.arriveAndAwaitAdvance();
        phaser.arriveAndAwaitAdvance();
        return System.nanoTime() - start;
    }

    static final class AdderTask implements Runnable {
        final LongAdder adder;
        final Phaser phaser;
        final long iters;
        volatile long result;
        AdderTask(LongAdder adder, Phaser phaser, long iters) {
            this.adder = adder;
            this.phaser = phaser;
            this.iters = iters;
        }

        public void run() {
            phaser.arriveAndAwaitAdvance();
            phaser.arriveAndAwaitAdvance();
            LongAdder a = adder;
            for (long i = 0; i < iters; ++i)
                a.increment();
            result = a.sum();
            phaser.arrive();
        }
    }

}
Revision:	1.5
Committed:	Mon Jan 26 17:52:44 2015 UTC (9 years, 3 months ago) by jsr166
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.4:	+39 -18 lines
Log Message:	make benchmark configurable from command line
#	User	Rev	Content
1	dl	1.1	/*
2			* Written by Doug Lea with assistance from members of JCP JSR-166
3			* Expert Group and released to the public domain, as explained at
4			* http://creativecommons.org/publicdomain/zero/1.0/
5			*/
6
7			import java.util.concurrent.atomic.LongAdder;
8			import java.util.concurrent.Executors;
9			import java.util.concurrent.ExecutorService;
10			import java.util.concurrent.Phaser;
11
12			public class LongAdderLoops {
13	jsr166	1.5	public static void main(String[] args) {
14			final int NCPU = Runtime.getRuntime().availableProcessors();
15			int minThreads = 1;
16			int maxThreads = 2 * NCPU;
17			long iters = 300_000_000L;
18			nextArg: for (String arg : args) {
19			String[] fields = arg.split("=");
20			if (fields.length == 2) {
21			String prop = fields[0], val = fields[1];
22			switch (prop) {
23			case "threads":
24			minThreads = maxThreads = Integer.valueOf(val);
25			continue nextArg;
26			case "minThreads":
27			minThreads = Integer.valueOf(val);
28			continue nextArg;
29			case "maxThreads":
30			maxThreads = Integer.valueOf(val);
31			continue nextArg;
32			case "iters":
33			iters = Long.valueOf(val);
34			continue nextArg;
35			}
36			}
37			throw new Error("Usage: LongAdderLoops minThreads=n maxThreads=n threads=n iters=n");
38			}
39	dl	1.1
40	jsr166	1.5	final ExecutorService pool = Executors.newCachedThreadPool();
41			for (int i = minThreads; i <= maxThreads; i += (i+1) >>> 1)
42			adderTest(pool, i, iters);
43	dl	1.1	pool.shutdown();
44			}
45
46	jsr166	1.5	static void adderTest(ExecutorService pool, int nthreads, long iters) {
47	dl	1.1	System.out.print("LongAdder ");
48			Phaser phaser = new Phaser(nthreads + 1);
49			LongAdder a = new LongAdder();
50			for (int i = 0; i < nthreads; ++i)
51	jsr166	1.5	pool.execute(new AdderTask(a, phaser, iters));
52			report(nthreads, iters, timeTasks(phaser), a.sum());
53	dl	1.1	}
54
55	jsr166	1.5	static void report(int nthreads, long iters, long time, long sum) {
56			long total = (long)nthreads * iters;
57	dl	1.1	if (sum != total)
58			throw new Error(sum + " != " + total);
59			double secs = (double)time / (1000L * 1000 * 1000);
60			long rate = total * (1000L) / time;
61	jsr166	1.5	System.out.printf("threads:%3d Time: %7.3fsec Iters per microsec: %4d\n",
62	dl	1.1	nthreads, secs, rate);
63			}
64
65			static long timeTasks(Phaser phaser) {
66			phaser.arriveAndAwaitAdvance();
67			long start = System.nanoTime();
68			phaser.arriveAndAwaitAdvance();
69			phaser.arriveAndAwaitAdvance();
70			return System.nanoTime() - start;
71			}
72
73			static final class AdderTask implements Runnable {
74			final LongAdder adder;
75			final Phaser phaser;
76	jsr166	1.5	final long iters;
77	dl	1.1	volatile long result;
78	jsr166	1.5	AdderTask(LongAdder adder, Phaser phaser, long iters) {
79	jsr166	1.2	this.adder = adder;
80	dl	1.1	this.phaser = phaser;
81	jsr166	1.5	this.iters = iters;
82	dl	1.1	}
83
84			public void run() {
85			phaser.arriveAndAwaitAdvance();
86			phaser.arriveAndAwaitAdvance();
87			LongAdder a = adder;
88	jsr166	1.5	for (long i = 0; i < iters; ++i)
89	dl	1.1	a.increment();
90			result = a.sum();
91			phaser.arrive();
92			}
93			}
94
95			}