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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/publicdomain/zero/1.0/ |
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*/ |
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|
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import java.util.concurrent.*; |
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import java.util.*; |
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|
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class ArraysSort { |
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static final long NPS = (1000L * 1000 * 1000); |
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static int THRESHOLD; |
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static Long[] numbers; |
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|
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static final Comparator<Object> cmp = (Object x, Object y) -> |
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((Long)x).compareTo((Long)y); |
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|
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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 reps = 30; |
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int sreps = 2; |
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try { |
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if (args.length > 0) |
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n = Integer.parseInt(args[0]); |
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if (args.length > 1) |
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reps = Integer.parseInt(args[1]); |
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} |
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catch (Exception e) { |
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System.out.println("Usage: java ArraysSort n reps"); |
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return; |
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} |
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|
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numbers = new Long[n]; |
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for (int i = 0; i < n; ++i) |
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numbers[i] = Long.valueOf(i); |
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|
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int thr = ((n + 7) >>> 3) / ForkJoinPool.getCommonPoolParallelism(); |
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THRESHOLD = (thr <= 1 << 13) ? 1 << 13 : thr; |
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|
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System.out.println("Threshold = " + THRESHOLD); |
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|
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Long[] a = new Long[n]; |
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ForkJoinPool pool = ForkJoinPool.commonPool(); |
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seqTest(a, n, 1); |
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System.out.println(pool); |
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parTest(a, n, reps); |
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System.out.println(pool); |
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seqTest(a, n, 2); |
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System.out.println(pool); |
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cseqTest(a, n, 1); |
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System.out.println(pool); |
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cparTest(a, n, reps); |
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System.out.println(pool); |
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cseqTest(a, n, 2); |
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System.out.println(pool); |
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} |
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|
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static void seqTest(Long[] a, int n, int reps) { |
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System.out.printf("Sorting %d longs, %d replications\n", n, reps); |
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long start = System.nanoTime(); |
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for (int i = 0; i < reps; ++i) { |
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new RandomRepacker(null, numbers, a, 0, n, n).invoke(); |
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long last = System.nanoTime(); |
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java.util.Arrays.sort(a); |
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long now = System.nanoTime(); |
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double total = (double)(now - start) / NPS; |
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double elapsed = (double)(now - last) / NPS; |
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System.out.printf("Arrays.sort time: %7.3f total %9.3f\n", |
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elapsed, total); |
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new OrderChecker(null, a, 0, n, n).invoke(); |
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} |
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} |
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|
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static void cseqTest(Long[] a, int n, int reps) { |
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System.out.printf("Sorting %d longs, %d replications\n", n, reps); |
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long start = System.nanoTime(); |
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for (int i = 0; i < reps; ++i) { |
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new RandomRepacker(null, numbers, a, 0, n, n).invoke(); |
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long last = System.nanoTime(); |
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java.util.Arrays.sort(a, cmp); |
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long now = System.nanoTime(); |
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double total = (double)(now - start) / NPS; |
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double elapsed = (double)(now - last) / NPS; |
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System.out.printf("Arrays.cmp sort time: %7.3f total %9.3f\n", |
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elapsed, total); |
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new OrderChecker(null, a, 0, n, n).invoke(); |
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} |
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} |
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|
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static void parTest(Long[] a, int n, int reps) throws Exception { |
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System.out.printf("Sorting %d longs, %d replications\n", n, reps); |
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long start = System.nanoTime(); |
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for (int i = 0; i < reps; ++i) { |
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new RandomRepacker(null, numbers, a, 0, n, n).invoke(); |
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long last = System.nanoTime(); |
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java.util.Arrays.parallelSort(a); |
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long now = System.nanoTime(); |
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double total = (double)(now - start) / NPS; |
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double elapsed = (double)(now - last) / NPS; |
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System.out.printf("Parallel sort time: %7.3f total %9.3f\n", |
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elapsed, total); |
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new OrderChecker(null, a, 0, n, n).invoke(); |
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} |
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} |
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|
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static void cparTest(Long[] a, int n, int reps) throws Exception { |
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System.out.printf("Sorting %d longs, %d replications\n", n, reps); |
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long start = System.nanoTime(); |
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for (int i = 0; i < reps; ++i) { |
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new RandomRepacker(null, numbers, a, 0, n, n).invoke(); |
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long last = System.nanoTime(); |
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java.util.Arrays.parallelSort(a, cmp); |
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long now = System.nanoTime(); |
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double total = (double)(now - start) / NPS; |
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double elapsed = (double)(now - last) / NPS; |
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System.out.printf("Par cmp sort time: %7.3f total %9.3f\n", |
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elapsed, total); |
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new OrderChecker(null, a, 0, n, n).invoke(); |
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} |
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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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long x = a[0].longValue(), y; |
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for (int i = 0; i < n - 1; i++) { |
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if (x > (y = a[i+1].longValue())) |
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throw new Error("Unsorted at " + i + ": " + x + " / " + y); |
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x = y; |
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} |
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} |
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|
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static final class RandomRepacker extends CountedCompleter<Void> { |
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final Long[] src; |
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final Long[] dst; |
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final int lo, hi, size; |
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RandomRepacker(CountedCompleter<?> par, Long[] src, Long[] dst, |
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int lo, int hi, int size) { |
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super(par); |
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this.src = src; this.dst = dst; |
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this.lo = lo; this.hi = hi; this.size = size; |
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} |
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|
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public final void compute() { |
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Long[] s = src; |
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Long[] d = dst; |
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int l = lo, h = hi, n = size; |
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while (h - l > THRESHOLD << 1) { |
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int m = (l + h) >>> 1; |
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addToPendingCount(1); |
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new RandomRepacker(this, s, d, m, h, n).fork(); |
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h = m; |
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} |
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ThreadLocalRandom rng = ThreadLocalRandom.current(); |
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Long dl = d[l]; |
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int m = (dl == null) ? h : rng.nextInt(l, h); |
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for (int i = l; i < m; ++i) |
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d[i] = s[rng.nextInt(n)]; |
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if (dl != null) { |
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dl = d[l]; |
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for (int i = m; i < h; ++i) |
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d[i] = dl; |
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} |
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tryComplete(); |
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} |
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} |
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|
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static final class OrderChecker extends CountedCompleter<Void> { |
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final Long[] array; |
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final int lo, hi, size; |
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OrderChecker(CountedCompleter<?> par, Long[] a, int lo, int hi, int size) { |
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super(par); |
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this.array = a; |
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this.lo = lo; this.hi = hi; this.size = size; |
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} |
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|
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public final void compute() { |
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Long[] a = this.array; |
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int l = lo, h = hi, n = size; |
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while (h - l > THRESHOLD) { |
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int m = (l + h) >>> 1; |
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addToPendingCount(1); |
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new OrderChecker(this, a, m, h, n).fork(); |
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h = m; |
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} |
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int bound = h < n ? h : n - 1; |
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int i = l; |
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long x = a[i].longValue(), y; |
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while (i < bound) { |
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if (x > (y = a[++i].longValue())) |
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throw new Error("Unsorted " + x + " / " + y); |
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x = y; |
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} |
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tryComplete(); |
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} |
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} |
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|
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} |
