test/extra166y/FindAnyDemo.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 extra166y.*;
import java.util.*;
import java.util.concurrent.*;


public class FindAnyDemo {
    static final int NCPU = Runtime.getRuntime().availableProcessors();

    /**
     * Sequential version, for performance comparison
     */
    static<T> int seqIndexOf(T[] array,
                             Ops.Predicate<T> pred) {
        int n = array.length;
        for (int i = 0; i < n; ++i) {
            T x = array[i];
            if (pred.op(x))
                return i;
        }
        return -1;
    }

    /**
     * Slow/dumb prime check
     */
    static class IsPrime implements Ops.Predicate<Rand> {
        public boolean op(Rand r) {
            long n = r.seed;
            int bound = (int)(Math.sqrt(n));
            if (bound >= 3) {
                for (int i = 3; i <= bound; ++i)
                    if ((n & 1) == 0 || n % i == 0)
                        return false;
            }
            return true;
        }
    }

    /** for time conversion */
    static final long NPS = (1000L * 1000 * 1000);

    static class NextRand implements Ops.Procedure<Rand> {
        public void op(Rand r) {
            r.next();
        }
    }

    public static void main(String[] args) throws Exception {
        int n = 1 << 20;
        ArrayList<Rand> list = new ArrayList<Rand>(n);
        long rs = 256203225;
        for (int i = 0; i < n >>> 1; ++i)
            list.add(new Rand(rs+=3));
        list.add(new Rand(256203221));
        for (int i = n >>> 1; i < n >>> 1; ++i)
            list.add(new Rand(rs+=3));
        Rand[] array = list.toArray(new Rand[0]);
        final IsPrime pred = new IsPrime();
        long last, now;
        double elapsed;
        boolean present = false;
        for (int k = 0; k < 2; ++k) {
            last = System.nanoTime();
            for (int reps = 0; reps < 9; ++reps) {
                int result = seqIndexOf(array, pred);
                if (k == 0 && reps == 0)
                    present = result != -1;
                else if (present != (result != -1))
                    throw new Error("Inconsistent result");
            }
            now = System.nanoTime();
            elapsed = (double)(now - last) / NPS;
            last = now;
            System.out.printf("seq:    %7.3f\n", elapsed);
        }
        Thread.sleep(100);
        ForkJoinPool fjp = new ForkJoinPool();
        ParallelArray<Rand> pa = ParallelArray.createUsingHandoff(array, fjp);
        for (int i = 1; i <= NCPU; i <<= 1) {
            last = System.nanoTime();
            for (int k = 0; k < 2; ++k) {
                for (int reps = 0; reps < 9; ++reps) {
                    int result = pa.withFilter(pred).anyIndex();
                    if (present != (result != -1))
                        throw new Error("Inconsistent result");
                }
                now = System.nanoTime();
                elapsed = (double)(now - last) / NPS;
                last = now;
                System.out.printf("ps %2d:  %7.3f\n", i, elapsed);
            }
        }
        fjp.shutdownNow();
        fjp.awaitTermination(1, TimeUnit.SECONDS);
    }

    /**
     * Unsynchronized version of java.util.Random algorithm.
     */
    static final class Rand {
        private static final long multiplier = 0x5DEECE66DL;
        private static final long addend = 0xBL;
        private static final long mask = (1L << 48) - 1;
        private long seed;

        Rand(long s) {
            seed = s;
            //            next();
            //            next();
        }
        public int next() {
            long nextseed = (seed * multiplier + addend) & mask;
            seed = nextseed;
            return ((int)(nextseed >>> 17)) & 0x7FFFFFFF;
        }

        public String toString() {
            return String.valueOf(seed);
        }
    }

}
Revision:	1.5
Committed:	Tue Mar 15 19:47:04 2011 UTC (13 years, 1 month ago) by jsr166
Branch:	MAIN
CVS Tags:	release-1_7_0, HEAD
Changes since 1.4:	+1 -1 lines
Log Message:	Update Creative Commons license URL in legal notices
#	Content
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 jsr166y.*;
8	import extra166y.*;
9	import java.util.*;
10	import java.util.concurrent.*;
11
12
13	public class FindAnyDemo {
14	static final int NCPU = Runtime.getRuntime().availableProcessors();
15
16	/**
17	* Sequential version, for performance comparison
18	*/
19	static<T> int seqIndexOf(T[] array,
20	Ops.Predicate<T> pred) {
21	int n = array.length;
22	for (int i = 0; i < n; ++i) {
23	T x = array[i];
24	if (pred.op(x))
25	return i;
26	}
27	return -1;
28	}
29
30	/**
31	* Slow/dumb prime check
32	*/
33	static class IsPrime implements Ops.Predicate<Rand> {
34	public boolean op(Rand r) {
35	long n = r.seed;
36	int bound = (int)(Math.sqrt(n));
37	if (bound >= 3) {
38	for (int i = 3; i <= bound; ++i)
39	if ((n & 1) == 0 \|\| n % i == 0)
40	return false;
41	}
42	return true;
43	}
44	}
45
46	/** for time conversion */
47	static final long NPS = (1000L * 1000 * 1000);
48
49	static class NextRand implements Ops.Procedure<Rand> {
50	public void op(Rand r) {
51	r.next();
52	}
53	}
54
55	public static void main(String[] args) throws Exception {
56	int n = 1 << 20;
57	ArrayList<Rand> list = new ArrayList<Rand>(n);
58	long rs = 256203225;
59	for (int i = 0; i < n >>> 1; ++i)
60	list.add(new Rand(rs+=3));
61	list.add(new Rand(256203221));
62	for (int i = n >>> 1; i < n >>> 1; ++i)
63	list.add(new Rand(rs+=3));
64	Rand[] array = list.toArray(new Rand[0]);
65	final IsPrime pred = new IsPrime();
66	long last, now;
67	double elapsed;
68	boolean present = false;
69	for (int k = 0; k < 2; ++k) {
70	last = System.nanoTime();
71	for (int reps = 0; reps < 9; ++reps) {
72	int result = seqIndexOf(array, pred);
73	if (k == 0 && reps == 0)
74	present = result != -1;
75	else if (present != (result != -1))
76	throw new Error("Inconsistent result");
77	}
78	now = System.nanoTime();
79	elapsed = (double)(now - last) / NPS;
80	last = now;
81	System.out.printf("seq: %7.3f\n", elapsed);
82	}
83	Thread.sleep(100);
84	ForkJoinPool fjp = new ForkJoinPool();
85	ParallelArray<Rand> pa = ParallelArray.createUsingHandoff(array, fjp);
86	for (int i = 1; i <= NCPU; i <<= 1) {
87	last = System.nanoTime();
88	for (int k = 0; k < 2; ++k) {
89	for (int reps = 0; reps < 9; ++reps) {
90	int result = pa.withFilter(pred).anyIndex();
91	if (present != (result != -1))
92	throw new Error("Inconsistent result");
93	}
94	now = System.nanoTime();
95	elapsed = (double)(now - last) / NPS;
96	last = now;
97	System.out.printf("ps %2d: %7.3f\n", i, elapsed);
98	}
99	}
100	fjp.shutdownNow();
101	fjp.awaitTermination(1, TimeUnit.SECONDS);
102	}
103
104	/**
105	* Unsynchronized version of java.util.Random algorithm.
106	*/
107	static final class Rand {
108	private static final long multiplier = 0x5DEECE66DL;
109	private static final long addend = 0xBL;
110	private static final long mask = (1L << 48) - 1;
111	private long seed;
112
113	Rand(long s) {
114	seed = s;
115	// next();
116	// next();
117	}
118	public int next() {
119	long nextseed = (seed * multiplier + addend) & mask;
120	seed = nextseed;
121	return ((int)(nextseed >>> 17)) & 0x7FFFFFFF;
122	}
123
124	public String toString() {
125	return String.valueOf(seed);
126	}
127	}
128
129	}