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
#	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	jsr166	1.5	* http://creativecommons.org/publicdomain/zero/1.0/
5	dl	1.1	*/
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	jsr166	1.2	static<T> int seqIndexOf(T[] array,
20	dl	1.1	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	jsr166	1.2	for (int i = 0; i < n >>> 1; ++i)
60	dl	1.1	list.add(new Rand(rs+=3));
61			list.add(new Rand(256203221));
62	jsr166	1.2	for (int i = n >>> 1; i < n >>> 1; ++i)
63	dl	1.1	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	dl	1.4	ForkJoinPool fjp = new ForkJoinPool();
85	dl	1.1	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	jsr166	1.3	private static final long multiplier = 0x5DEECE66DL;
109			private static final long addend = 0xBL;
110			private static final long mask = (1L << 48) - 1;
111	dl	1.1	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	jsr166	1.2	return String.valueOf(seed);
126	dl	1.1	}
127			}
128
129			}