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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/licenses/publicdomain |
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*/ |
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|
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import jsr166y.*; |
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import extra166y.*; |
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import java.util.*; |
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|
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class SortDemo { |
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|
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static final Random rng = new Random(); |
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static final long NPS = (1000L * 1000 * 1000); |
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|
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public static void main (String[] args) throws Exception { |
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int n = 1 << 22; |
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int sreps = 4; |
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int reps = 20; |
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Long[] a = new Long[n]; |
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ForkJoinPool fjpool = new ForkJoinPool(); |
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ParallelArray<Long> pa = ParallelArray.createUsingHandoff(a, fjpool); |
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|
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System.out.printf("Parallel Sort %d Longs, %d replications\n", n, reps); |
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for (int i = 0; i < reps; ++i) { |
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pa.replaceWithGeneratedValue(rlg); |
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parSort(pa); |
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if (i == 0) |
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checkSorted(a); |
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} |
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System.out.printf("Sequential Sort %d Longs, %d replications\n", n, sreps); |
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for (int i = 0; i < sreps; ++i) { |
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pa.replaceWithGeneratedValue(rlg); |
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seqSort(a); |
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if (i == 0) |
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checkSorted(a); |
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} |
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|
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System.out.println(fjpool); |
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fjpool.shutdown(); |
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} |
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|
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static void seqSort(Long[] a) { |
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long last = System.nanoTime(); |
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java.util.Arrays.sort(a); |
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double elapsed = (double)(System.nanoTime() - last) / NPS; |
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System.out.printf("java.util.Arrays.sort time: %7.3f\n", elapsed); |
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} |
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|
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static void parSort(ParallelArray<Long> pa) { |
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long last = System.nanoTime(); |
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pa.sort(); |
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double elapsed = (double)(System.nanoTime() - last) / NPS; |
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System.out.printf("ParallelArray.sort time: %7.3f\n", elapsed); |
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} |
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|
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static void checkSorted(Long[] a) { |
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int n = a.length; |
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for (int i = 0; i < n - 1; i++) { |
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if (a[i].compareTo(a[i+1]) > 0) { |
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throw new Error("Unsorted at " + i + ": " + a[i] + " / " + a[i+1]); |
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} |
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} |
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} |
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|
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static final class RandomLongGenerator implements Ops.Generator<Long> { |
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public Long op() { |
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return new Long(ThreadLocalRandom.current().nextLong()); |
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} |
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} |
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|
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static final RandomLongGenerator rlg = new RandomLongGenerator(); |
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|
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|
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|
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} |