test/loops/ExchangeLoops.java

/*
 * Written by Bill Scherer and 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.*;
import java.util.concurrent.locks.*;

public class ExchangeLoops {
    static final int NCPUS = Runtime.getRuntime().availableProcessors();

    static final int  DEFAULT_THREADS = NCPUS + 2;
    static final long DEFAULT_TRIAL_MILLIS   = 10000;

    public static void main(String[] args) throws Exception {
        int maxThreads = DEFAULT_THREADS;
        long trialMillis = DEFAULT_TRIAL_MILLIS;
        int nReps = 3;

        // Parse and check args
        int argc = 0;
        while (argc < args.length) {
            String option = args[argc++];
            if (option.equals("-t"))
                trialMillis = Integer.parseInt(args[argc]);
            else if (option.equals("-r"))
                nReps = Integer.parseInt(args[argc]);
            else 
                maxThreads = Integer.parseInt(option);
            argc++;
        }

        // Display runtime parameters
        System.out.print("ExchangeTest");
        System.out.print(" -t " + trialMillis);
        System.out.print(" -r " + nReps);
        System.out.print(" max threads " + maxThreads);
        System.out.println();
        long warmupTime = 2000;
        long sleepTime = 100;
        int nw = maxThreads >= 3? 3 : 2;

        System.out.println("Warmups..");
        oneRun(3, warmupTime);
        Thread.sleep(sleepTime);

        for (int i = maxThreads; i >= 2; i -= 1) {
            oneRun(i, warmupTime++);
            //            System.gc();
            Thread.sleep(sleepTime);
        }

        /*
        for (int i = maxThreads; i >= 2; i -= 1) {
            oneRun(i, warmupTime++);
        }
        */

        for (int j = 0; j < nReps; ++j) {
            System.out.println("Trial: " + j);
            for (int i = 2; i <= maxThreads; i += 2) {
                oneRun(i, trialMillis);
                //                System.gc();
                Thread.sleep(sleepTime);
            }
            for (int i = maxThreads; i >= 2; i -= 2) {
                oneRun(i, trialMillis);
                //                System.gc();
                Thread.sleep(sleepTime);
            }
            Thread.sleep(sleepTime);
        }


    }

    static void oneRun(int nThreads, long trialMillis) throws Exception {
        System.out.printf("%4d threads", nThreads);
        System.out.printf("%9dms", trialMillis);
        Exchanger x = new Exchanger();
        Runner[] runners = new Runner[nThreads];
        Thread[] threads = new Thread[nThreads];
        for (int i = 0; i < nThreads; ++i) {
            runners[i] = new Runner(x);
            threads[i] = new Thread(runners[i]);
            //            int h = System.identityHashCode(threads[i]);
            //            h ^= h << 1;
            //            h ^= h >>> 3;
            //            h ^= h << 10;
            //            System.out.printf("%10x\n", h);
        }

        long startTime = System.nanoTime();
        for (int i = 0; i < nThreads; ++i) {
            threads[i].start();
        }
        Thread.sleep(trialMillis);
        for (int i = 0; i < nThreads; ++i) 
            threads[i].interrupt();
        long elapsed = System.nanoTime() - startTime;
        for (int i = 0; i < nThreads; ++i) 
            threads[i].join();
        int iters = 1;
        //        System.out.println();
        for (int i = 0; i < nThreads; ++i) {
            int ipr = runners[i].iters;
            //            System.out.println(ipr);
            iters += ipr;
        }
        long rate = iters * 1000L * 1000L * 1000L / elapsed;
        long npt = elapsed / iters;
        System.out.printf("%9d it/s ", rate);
        System.out.printf("%9d ns/it", npt);
        System.out.println();
        //        x.printStats();
    }
       
    static final class Runner implements Runnable {
        final Exchanger exchanger;
        final Object mine = new Integer(2688);
        volatile int iters;
        Runner(Exchanger x) { this.exchanger = x; }

        public void run() {
            Exchanger x = exchanger;
            Object m = mine;
            int i = 0;
            try {
                for (;;) {
                    Object e = x.exchange(m);
                    if (e == null || e == m)
                        throw new Error();
                    m = e;
                    ++i;
                }
            } catch (InterruptedException ie) {
                iters = i;
            }
        }
    }
}
        
Revision:	1.2
Committed:	Mon Feb 13 12:39:23 2006 UTC (18 years, 3 months ago) by dl
Branch:	MAIN
Changes since 1.1:	+124 -84 lines
Log Message:	Update exchanger tests
#	User	Rev	Content
1	dl	1.1	/*
2	dl	1.2	* Written by Bill Scherer and Doug Lea with assistance from members
3			* of JCP JSR-166 Expert Group and released to the public domain. Use,
4			* modify, and redistribute this code in any way without
5			* acknowledgement.
6	dl	1.1	*/
7
8			import java.util.concurrent.*;
9	dl	1.2	import java.util.concurrent.atomic.*;
10			import java.util.concurrent.locks.*;
11	dl	1.1
12			public class ExchangeLoops {
13	dl	1.2	static final int NCPUS = Runtime.getRuntime().availableProcessors();
14	dl	1.1
15	dl	1.2	static final int DEFAULT_THREADS = NCPUS + 2;
16			static final long DEFAULT_TRIAL_MILLIS = 10000;
17	dl	1.1
18			public static void main(String[] args) throws Exception {
19	dl	1.2	int maxThreads = DEFAULT_THREADS;
20			long trialMillis = DEFAULT_TRIAL_MILLIS;
21			int nReps = 3;
22
23			// Parse and check args
24			int argc = 0;
25			while (argc < args.length) {
26			String option = args[argc++];
27			if (option.equals("-t"))
28			trialMillis = Integer.parseInt(args[argc]);
29			else if (option.equals("-r"))
30			nReps = Integer.parseInt(args[argc]);
31			else
32			maxThreads = Integer.parseInt(option);
33			argc++;
34			}
35	dl	1.1
36	dl	1.2	// Display runtime parameters
37			System.out.print("ExchangeTest");
38			System.out.print(" -t " + trialMillis);
39			System.out.print(" -r " + nReps);
40			System.out.print(" max threads " + maxThreads);
41			System.out.println();
42			long warmupTime = 2000;
43			long sleepTime = 100;
44			int nw = maxThreads >= 3? 3 : 2;
45
46			System.out.println("Warmups..");
47			oneRun(3, warmupTime);
48			Thread.sleep(sleepTime);
49
50			for (int i = maxThreads; i >= 2; i -= 1) {
51			oneRun(i, warmupTime++);
52			// System.gc();
53			Thread.sleep(sleepTime);
54			}
55	dl	1.1
56	dl	1.2	/*
57			for (int i = maxThreads; i >= 2; i -= 1) {
58			oneRun(i, warmupTime++);
59	dl	1.1	}
60	dl	1.2	*/
61	dl	1.1
62	dl	1.2	for (int j = 0; j < nReps; ++j) {
63			System.out.println("Trial: " + j);
64			for (int i = 2; i <= maxThreads; i += 2) {
65			oneRun(i, trialMillis);
66			// System.gc();
67			Thread.sleep(sleepTime);
68	dl	1.1	}
69	dl	1.2	for (int i = maxThreads; i >= 2; i -= 2) {
70			oneRun(i, trialMillis);
71			// System.gc();
72			Thread.sleep(sleepTime);
73	dl	1.1	}
74	dl	1.2	Thread.sleep(sleepTime);
75	dl	1.1	}
76	dl	1.2
77
78	dl	1.1	}
79
80	dl	1.2	static void oneRun(int nThreads, long trialMillis) throws Exception {
81			System.out.printf("%4d threads", nThreads);
82			System.out.printf("%9dms", trialMillis);
83			Exchanger x = new Exchanger();
84			Runner[] runners = new Runner[nThreads];
85			Thread[] threads = new Thread[nThreads];
86			for (int i = 0; i < nThreads; ++i) {
87			runners[i] = new Runner(x);
88			threads[i] = new Thread(runners[i]);
89			// int h = System.identityHashCode(threads[i]);
90			// h ^= h << 1;
91			// h ^= h >>> 3;
92			// h ^= h << 10;
93			// System.out.printf("%10x\n", h);
94			}
95
96			long startTime = System.nanoTime();
97			for (int i = 0; i < nThreads; ++i) {
98			threads[i].start();
99			}
100			Thread.sleep(trialMillis);
101			for (int i = 0; i < nThreads; ++i)
102			threads[i].interrupt();
103			long elapsed = System.nanoTime() - startTime;
104			for (int i = 0; i < nThreads; ++i)
105			threads[i].join();
106			int iters = 1;
107			// System.out.println();
108			for (int i = 0; i < nThreads; ++i) {
109			int ipr = runners[i].iters;
110			// System.out.println(ipr);
111			iters += ipr;
112			}
113			long rate = iters * 1000L * 1000L * 1000L / elapsed;
114			long npt = elapsed / iters;
115			System.out.printf("%9d it/s ", rate);
116			System.out.printf("%9d ns/it", npt);
117			System.out.println();
118			// x.printStats();
119	dl	1.1	}
120	dl	1.2
121			static final class Runner implements Runnable {
122			final Exchanger exchanger;
123			final Object mine = new Integer(2688);
124			volatile int iters;
125			Runner(Exchanger x) { this.exchanger = x; }
126	dl	1.1
127	dl	1.2	public void run() {
128			Exchanger x = exchanger;
129			Object m = mine;
130			int i = 0;
131			try {
132			for (;;) {
133			Object e = x.exchange(m);
134			if (e == null \|\| e == m)
135			throw new Error();
136			m = e;
137			++i;
138			}
139			} catch (InterruptedException ie) {
140			iters = i;
141			}
142			}
143			}
144	dl	1.1	}
145	dl	1.2