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* http://creativecommons.org/licenses/publicdomain |
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*/ |
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import java.util.*; |
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import java.util.concurrent.*; |
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// Based very loosely on cilksort |
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import java.util.*; |
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class ScalarLongSort { |
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static final long NPS = (1000L * 1000 * 1000); // time conversion |
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static final long NPS = (1000L * 1000 * 1000); |
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|
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static int THRESHOLD; |
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static final boolean warmup = true; |
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|
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public static void main(String[] args) throws Exception { |
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public static void main (String[] args) throws Exception { |
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int procs = 0; |
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int n = 1 << 22; |
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int sreps = 2; |
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int reps = 20; |
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int sreps = 2; |
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try { |
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if (args.length > 0) |
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procs = Integer.parseInt(args[0]); |
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if (args.length > 1) |
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n = Integer.parseInt(args[1]); |
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if (args.length > 2) |
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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 ScalarLongSort threads n reps"); |
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return; |
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} |
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ForkJoinPool pool = procs == 0? new ForkJoinPool() : |
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new ForkJoinPool(procs); |
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|
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long[] a = new long[n]; |
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seqRandomFill(a, 0, n); |
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|
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if (warmup) { |
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System.out.printf("Sorting %d longs, %d replications\n", n, 1); |
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checkSorted(a); |
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} |
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ForkJoinPool pool = new ForkJoinPool(); |
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// for now hardwire 8 * #CPUs leaf tasks |
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THRESHOLD = 1 + ((n + 7) >>> 3) / pool.getParallelism(); |
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// THRESHOLD = 1 + ((n + 15) >>> 4) / pool.getParallelism(); |
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} |
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static final class Sorter extends RecursiveAction { |
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final long[] a; |
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final long[] a; |
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final long[] w; |
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final int origin; |
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final int origin; |
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final int n; |
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Sorter(long[] a, long[] w, int origin, int n) { |
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this.a = a; this.w = w; this.origin = origin; this.n = n; |
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if (n <= THRESHOLD) |
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Arrays.sort(a, l, l+n); |
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else { // divide in quarters to ensure sorted array in a not w |
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SubSorter rs; |
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int h = n >>> 1; |
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int q = n >>> 2; |
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int u = h + q; |
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(rs = new SubSorter |
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(new Sorter(a, w, l+h, q), |
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new Sorter(a, w, l+u, n-u), |
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new Merger(a, w, l+h, q, l+u, n-u, l+h, null))).fork(); |
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(new SubSorter |
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(new Sorter(a, w, l, q), |
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new Sorter(a, w, l+q, h-q), |
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new Merger(a, w, l, q, l+q, h-q, l, null))).compute(); |
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SubSorter rs = new SubSorter |
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(new Sorter(a, w, l+h, q), |
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new Sorter(a, w, l+u, n-u), |
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new Merger(a, w, l+h, q, l+u, n-u, l+h, null)); |
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rs.fork(); |
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Sorter rl = new Sorter(a, w, l+q, h-q); |
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rl.fork(); |
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(new Sorter(a, w, l, q)).compute(); |
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rl.join(); |
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(new Merger(a, w, l, q, l+q, h-q, l, null)).compute(); |
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rs.join(); |
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new Merger(w, a, l, h, l+h, n-h, l, null).compute(); |
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} |
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} |
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} |
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|
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static final class SubSorter extends RecursiveAction { |
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final Sorter left; |
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final Sorter right; |
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static final class Merger extends RecursiveAction { |
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final long[] a; final long[] w; |
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final int lo; final int ln; final int ro; final int rn; final int wo; |
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final Merger next; |
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Merger next; |
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Merger(long[] a, long[] w, int lo, int ln, int ro, int rn, int wo, |
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Merger next) { |
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this.a = a; this.w = w; |
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* and finding index of right closest to split point. |
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* Uses left-spine decomposition to generate all |
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* merge tasks before bottomming out at base case. |
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* |
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* |
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*/ |
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public void compute() { |
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public final void compute() { |
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Merger rights = null; |
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int nleft = ln; |
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int nright = rn; |
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nleft = lh; |
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nright = rh; |
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} |
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|
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merge(nleft, nright); |
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if (rights != null) |
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collectRights(rights); |
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|
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} |
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// Base case -- merge left and right |
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final void merge(int nleft, int nright) { |
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int l = lo; |
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int lFence = lo + nleft; |
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int r = ro; |
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w[k++] = a[l++]; |
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while (r < rFence) |
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w[k++] = a[r++]; |
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} |
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while (rights != null) { |
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rights.join(); |
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rights = rights.next; |
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static void collectRights(Merger rt) { |
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while (rt != null) { |
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Merger next = rt.next; |
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rt.next = null; |
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if (rt.tryUnfork()) rt.compute(); else rt.join(); |
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rt = next; |
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} |
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} |
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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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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] > a[i+1]) { |
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throw new Error("Unsorted at " + i + ": " + |
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throw new Error("Unsorted at " + i + ": " + |
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a[i] + " / " + a[i+1]); |
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} |
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} |
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this.array = array; this.lo = lo; this.hi = hi; |
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} |
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public void compute() { |
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if (hi - lo <= THRESHOLD) |
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seqRandomFill(array, lo, hi); |
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if (hi - lo <= THRESHOLD) { |
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long[] a = array; |
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ThreadLocalRandom rng = ThreadLocalRandom.current(); |
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for (int i = lo; i < hi; ++i) |
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a[i] = rng.nextLong(); |
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} |
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else { |
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int mid = (lo + hi) >>> 1; |
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RandomFiller r = new RandomFiller(array, mid, hi); |