l'exécution de code java donne des résultats différents dans le débogage sans points de rupture et l'exécution normale. ExecutorService est-il cassé?

TL: DR ExecutorService executorService = Executors.newFixedThreadPool(8); dans debug s'exécute concurremment, mais dans le temps d'exécution normal, il démarre concurremment, mais s'exécute plus tard en thread simple.

j'ai un code où je commence 4 tâches différentes dans ExecutorService . Deux de ces tâches devraient terminer presque instantanément, les deux autres devraient fonctionner pendant un certain temps.

les tâches de retour le temps d'exécution en secondes dans Future<Double> .

ce code est responsable de l'exécution des tâches et mesure:

public Future<Double> measure(int[] arr, ProcessIntArray processIntArray, ExecutorService es) {
    Callable<Double> task = () -> {
        long start = System.nanoTime();
        processIntArray.process(arr);
        long end = System.nanoTime();
        return (end - start) / 1000000000.0;
    };
    return es.submit(task);
}

plus tard, après avoir commencé ces tâches, je les imprime dans l'ordre de temps d'exécution des précédentes éditions pour la même taille d'entrée.

    Future<Double> bubbleSortTime = measure(bubbleSortArray, Solution::bubbleSort, executorService);
    Future<Double> insertionSortTime = measure(insertionSortArray, Solution::insertionSort, executorService);
    Future<Double> quickSortTime = measure(quickSortArray, Solution::quickSort, executorService);
    Future<Double> mergeSortTime = measure(mergeSortArray, Solution::mergeSort, executorService);


    System.out.println();
    System.out.println("array size:     " + size);
    System.out.println("quick sort:     " + quickSortTime.get() + "s");
    System.out.println("merge sort:     " + mergeSortTime.get() + "s");
    System.out.println("insertion sort: " + insertionSortTime.get() + "s");
    System.out.println("bubble sort:    " + bubbleSortTime.get() + "s");

quand j'exécute le code en mode debug, 2 résultats sont imprimés immédiatement, et je dois attendre un peu pour le 3ème résultat (Je ne me donne pas la peine d'attendre le 4ème).

après debug (correct et attendu):

array size: 1000000 quick sort: 0.186892839s merge sort: 0.291950604s insertion sort: 344.534256723s

l'exécution normale diffère, on dirait que dans la mesure de la méthode long start = System.nanoTime(); est exécutée, puis le thread s'endort, et après insertionSort est fait, quickSort est de retour dans l'exécution, ce qui donne à la sortie:

array size: 1000000 quick sort: 345.893922141s merge sort: 345.944023095s insertion sort: 345.871908569s

ce qui est faux. Tous ces threads devraient être lancés en même temps, à partir de newFixedThreadPool javadoc.

/**
 * Creates a thread pool that reuses a fixed number of threads
 * operating off a shared unbounded queue.  At any point, at most
 * {@code nThreads} threads will be active processing tasks.
 * If additional tasks are submitted when all threads are active,
 * they will wait in the queue until a thread is available.
 * If any thread terminates due to a failure during execution
 * prior to shutdown, a new one will take its place if needed to
 * execute subsequent tasks.  The threads in the pool will exist
 * until it is explicitly {@link ExecutorService#shutdown shutdown}.
 *
 * @param nThreads the number of threads in the pool
 * @return the newly created thread pool
 * @throws IllegalArgumentException if {@code nThreads <= 0}
 */
public static ExecutorService newFixedThreadPool(int nThreads)

je joins le code source:

import java.util.Arrays;
import java.util.Random;
import java.util.concurrent.*;

class ThreadedSortingComparsion {
    Random random = new Random(System.currentTimeMillis());

    void popul(int[] array) {
        for (int i = 0; i < array.length; i++) {
            array[i] = random.nextInt();
        }
    }

    interface ArraySorter {
        void sort(int[] array);
    }

    public Future<Double> measureTime(int[] array, ArraySorter arraySorter, ExecutorService executorService) {
        Callable<Double> task = () -> {
            long start = System.nanoTime();
            arraySorter.sort(array);
            long end = System.nanoTime();
            return (end - start) / 1000000000.0;
        };
        return executorService.submit(task);
    }


    public void start() throws ExecutionException, InterruptedException {
        ExecutorService executorService = Executors.newFixedThreadPool(8);

        int size = 1000 * 1000;
        int[] quickSortArray = new int[size];
        popul(quickSortArray);
        int[] bubbleSortArray = Arrays.copyOf(quickSortArray, quickSortArray.length);
        int[] mergeSortArray = Arrays.copyOf(quickSortArray, quickSortArray.length);
        int[] originalArray = Arrays.copyOf(quickSortArray, quickSortArray.length);
        int[] insertionSortArray = Arrays.copyOf(quickSortArray, quickSortArray.length);

        Future<Double> bubbleSortTime = measureTime(bubbleSortArray, ThreadedSortingComparsion::bubbleSort, executorService);
        Future<Double> insertionSortTime = measureTime(insertionSortArray, ThreadedSortingComparsion::insertionSort, executorService);
        Future<Double> quickSortTime = measureTime(quickSortArray, ThreadedSortingComparsion::quickSort, executorService);
        Future<Double> mergeSortTime = measureTime(mergeSortArray, ThreadedSortingComparsion::mergeSort, executorService);


        System.out.println();
        System.out.println("array size:     " + size);
        System.out.println("quick sort:     " + quickSortTime.get() + "s");
        System.out.println("merge sort:     " + mergeSortTime.get() + "s");
        System.out.println("insertion sort: " + insertionSortTime.get() + "s");
        System.out.println("bubble sort:    " + bubbleSortTime.get() + "s");
        executorService.shutdown();

        for (int i = 0; i < quickSortArray.length; i++) {
            if (quickSortArray[i] != bubbleSortArray[i] || quickSortArray[i] != mergeSortArray[i] || quickSortArray[i] != insertionSortArray[i]) {
                throw new RuntimeException(Arrays.toString(originalArray));
            }
        }
    }


    public static void mergeSort(int[] ar) {
        if (ar.length < 5) {
            bubbleSort(ar);
            return;
        }
        int middle = ar.length / 2;
        int[] arrayLeft = new int[middle];
        int[] arrayRight = new int[ar.length - middle];
        for (int i = 0; i < ar.length; i++) {
            if (i < middle) {
                arrayLeft[i] = ar[i];
            } else {
                arrayRight[i - middle] = ar[i];
            }
        }
        mergeSort(arrayLeft);
        mergeSort(arrayRight);
        int indexLeft = 0;
        int indexRight = 0;
        int inputArrayIndex = 0;
        while (true) {
            int whatToPutInAR = 0;
            if (indexLeft != arrayLeft.length && indexRight != arrayRight.length) {
                if (arrayLeft[indexLeft] < arrayRight[indexRight]) {
                    whatToPutInAR = arrayLeft[indexLeft];
                    indexLeft++;
                } else {
                    whatToPutInAR = arrayRight[indexRight];
                    indexRight++;
                }
            } else if (indexLeft != arrayLeft.length) {
                whatToPutInAR = arrayLeft[indexLeft];
                indexLeft++;
            } else if (indexRight != arrayRight.length) {
                whatToPutInAR = arrayRight[indexRight];
                indexRight++;
            }
            if (inputArrayIndex == ar.length) return;
            ar[inputArrayIndex++] = whatToPutInAR;
        }
    }

    private static void quickSort(int[] ar) {
        quickSort(ar, 0, ar.length);
    }

    static public void quickSort(int[] array, int start, int end) {
        boolean changed = false;
        if (end == 0) return;
        int pivot = array[end - 1];
        int partitionCandidate = start;
        for (int i = start; i < end; i++) {
            if (array[i] < pivot) {
                swap(array, partitionCandidate++, i);
                changed = true;
            } else if (pivot < array[i]) {
                swap(array, end - 1, i);
                changed = true;
            }
        }
        if (start < partitionCandidate) {
            quickSort(array, start, partitionCandidate);
        }
        if (partitionCandidate < end) {
            if (partitionCandidate != start || changed) quickSort(array, partitionCandidate, end);
        }
    }


    public static void swap(int[] ar, int from, int to) {
        int old = ar[from];
        ar[from] = ar[to];
        ar[to] = old;
    }

    public static void bubbleSort(int[] array) {
        for (int i = 0; i < array.length; i++) {
            for (int j = 0; j < array.length - 1; j++) {
                if (array[j] > array[j + 1]) {
                    swap(array, j + 1, j);
                }
            }
        }
    }

    private static void insertionSort(int[] ar) {
        for (int i = 0; i < ar.length; i++) {
            for (int j = i; j >= 1; j--) {
                boolean breaker = true;
                if (ar[j] < ar[j - 1]) {
                    breaker = false;
                    swap(ar, j - 1, j);
                }
                if (breaker) break;
            }
        }
    }

    public static void main(String[] args) throws ExecutionException, InterruptedException {
        ThreadedSortingComparsion s = new ThreadedSortingComparsion();
        s.start();
    }
}

Edit: quand je l'exécute dans Ideone, le code fonctionne très bien. http://ideone.com/1E8C51 Ideone a la version java 1.8.0_51 J'ai testé sur 1.8.0_91 , 1.8.0_92 . Et 1.8.0_45 . Pourquoi cela fonctionne sur ideone, mais pas sur 2 autres PC que j'ai testé?

quand je fais le dump thread, tout en exécutant pas dans le debug, alors j'attends un peu, et après le dump thread est imprimé, aussi les résultats sont imprimés. Donc le dump de fil est fait après avoir terminé le tri d'insertion.

"C:Program FilesJavajdk1.8.0_45binjava" -Xmx8G -Xss1G -Didea.launcher.port=7533 "-Didea.launcher.bin.path=C:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.1.3bin" -Dfile.encoding=UTF-8 -classpath "C:Program FilesJavajdk1.8.0_45jrelibcharsets.jar;C:Program FilesJavajdk1.8.0_45jrelibdeploy.jar;C:Program FilesJavajdk1.8.0_45jrelibextaccess-bridge-64.jar;C:Program FilesJavajdk1.8.0_45jrelibextcldrdata.jar;C:Program FilesJavajdk1.8.0_45jrelibextdnsns.jar;C:Program FilesJavajdk1.8.0_45jrelibextjaccess.jar;C:Program FilesJavajdk1.8.0_45jrelibextjfxrt.jar;C:Program FilesJavajdk1.8.0_45jrelibextlocaledata.jar;C:Program FilesJavajdk1.8.0_45jrelibextnashorn.jar;C:Program FilesJavajdk1.8.0_45jrelibextsunec.jar;C:Program FilesJavajdk1.8.0_45jrelibextsunjce_provider.jar;C:Program FilesJavajdk1.8.0_45jrelibextsunmscapi.jar;C:Program FilesJavajdk1.8.0_45jrelibextsunpkcs11.jar;C:Program FilesJavajdk1.8.0_45jrelibextzipfs.jar;C:Program FilesJavajdk1.8.0_45jrelibjavaws.jar;C:Program FilesJavajdk1.8.0_45jrelibjce.jar;C:Program FilesJavajdk1.8.0_45jrelibjfr.jar;C:Program FilesJavajdk1.8.0_45jrelibjfxswt.jar;C:Program FilesJavajdk1.8.0_45jrelibjsse.jar;C:Program FilesJavajdk1.8.0_45jrelibmanagement-agent.jar;C:Program FilesJavajdk1.8.0_45jrelibplugin.jar;C:Program FilesJavajdk1.8.0_45jrelibresources.jar;C:Program FilesJavajdk1.8.0_45jrelibrt.jar;C:UsersTomasz_MielczarskiIdeaProjectsuntitledoutproductionuntitled;C:Program Files (x86)JetBrainsIntelliJ IDEA Community Edition 2016.1.3libidea_rt.jar" com.intellij.rt.execution.application.AppMain ThreadedSortingComparsion

array size:     1000000
2016-07-15 13:45:22
Full thread dump Java HotSpot(TM) 64-Bit Server VM (25.45-b02 mixed mode):

"pool-1-thread-4" #15 prio=5 os_prio=0 tid=0x00000000696bd000 nid=0x560 runnable [0x00000002fffee000]
   java.lang.Thread.State: RUNNABLE
    at ThreadedSortingComparsion.mergeSort(ThreadedSortingComparsion.java:77)
    at ThreadedSortingComparsion.mergeSort(ThreadedSortingComparsion.java:78)
    at ThreadedSortingComparsion.mergeSort(ThreadedSortingComparsion.java:78)
    at ThreadedSortingComparsion.mergeSort(ThreadedSortingComparsion.java:78)
    at ThreadedSortingComparsion.mergeSort(ThreadedSortingComparsion.java:77)
    at ThreadedSortingComparsion$$Lambda/81628611.sort(Unknown Source)
    at ThreadedSortingComparsion.lambda$measureTime"151940920"(ThreadedSortingComparsion.java:21)
    at ThreadedSortingComparsion$$Lambda/1023892928.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

"pool-1-thread-3" #14 prio=5 os_prio=0 tid=0x00000000696bb800 nid=0x2634 runnable [0x00000002bffee000]
   java.lang.Thread.State: RUNNABLE
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:123)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:126)
    at ThreadedSortingComparsion.quickSort(ThreadedSortingComparsion.java:105)
    at ThreadedSortingComparsion$$Lambda/1989780873.sort(Unknown Source)
    at ThreadedSortingComparsion.lambda$measureTime"151940920"(ThreadedSortingComparsion.java:21)
    at ThreadedSortingComparsion$$Lambda/1023892928.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

"pool-1-thread-2" #13 prio=5 os_prio=0 tid=0x00000000696b7800 nid=0x1c70 waiting on condition [0x000000027ffef000]
   java.lang.Thread.State: WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x0000000719d72480> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
    at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
    at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

"pool-1-thread-1" #12 prio=5 os_prio=0 tid=0x00000000696b6800 nid=0x478 runnable [0x000000023ffee000]
   java.lang.Thread.State: RUNNABLE
    at ThreadedSortingComparsion.bubbleSort(ThreadedSortingComparsion.java:139)
    at ThreadedSortingComparsion$$Lambda/990368553.sort(Unknown Source)
    at ThreadedSortingComparsion.lambda$measureTime"151940920"(ThreadedSortingComparsion.java:21)
    at ThreadedSortingComparsion$$Lambda/1023892928.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

"Monitor Ctrl-Break" #11 daemon prio=5 os_prio=0 tid=0x0000000068d3d000 nid=0x2f3c runnable [0x00000001fffee000]
   java.lang.Thread.State: RUNNABLE
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
    at java.net.SocketInputStream.read(SocketInputStream.java:170)
    at java.net.SocketInputStream.read(SocketInputStream.java:141)
    at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
    at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
    at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
    - locked <0x00000007156892b8> (a java.io.InputStreamReader)
    at java.io.InputStreamReader.read(InputStreamReader.java:184)
    at java.io.BufferedReader.fill(BufferedReader.java:161)
    at java.io.BufferedReader.readLine(BufferedReader.java:324)
    - locked <0x00000007156892b8> (a java.io.InputStreamReader)
    at java.io.BufferedReader.readLine(BufferedReader.java:389)
    at com.intellij.rt.execution.application.AppMain.run(AppMain.java:93)
    at java.lang.Thread.run(Thread.java:745)

"Service Thread" #10 daemon prio=9 os_prio=0 tid=0x0000000068c81000 nid=0x2d6c runnable [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"C1 CompilerThread3" #9 daemon prio=9 os_prio=2 tid=0x0000000068bea800 nid=0x1ad0 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"C2 CompilerThread2" #8 daemon prio=9 os_prio=2 tid=0x0000000068be4000 nid=0x17d0 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"C2 CompilerThread1" #7 daemon prio=9 os_prio=2 tid=0x0000000068bdd800 nid=0x3238 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"C2 CompilerThread0" #6 daemon prio=9 os_prio=2 tid=0x0000000068bda000 nid=0x1824 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Attach Listener" #5 daemon prio=5 os_prio=2 tid=0x0000000068bd8800 nid=0x910 runnable [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Signal Dispatcher" #4 daemon prio=9 os_prio=2 tid=0x0000000068bd7800 nid=0x31f8 waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Finalizer" #3 daemon prio=8 os_prio=1 tid=0x0000000043229800 nid=0x2810 in Object.wait() [0x00000000fffee000]
   java.lang.Thread.State: WAITING (on object monitor)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x0000000719d707e0> (a java.lang.ref.ReferenceQueue$Lock)
    at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
    - locked <0x0000000719d707e0> (a java.lang.ref.ReferenceQueue$Lock)
    at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
    at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)

"Reference Handler" #2 daemon prio=10 os_prio=2 tid=0x0000000043223000 nid=0xd48 in Object.wait() [0x00000000bffef000]
   java.lang.Thread.State: WAITING (on object monitor)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x0000000719d78370> (a java.lang.ref.Reference$Lock)
    at java.lang.Object.wait(Object.java:502)
    at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:157)
    - locked <0x0000000719d78370> (a java.lang.ref.Reference$Lock)

"main" #1 prio=5 os_prio=0 tid=0x000000000311d800 nid=0x2ed0 waiting on condition [0x000000004311e000]
   java.lang.Thread.State: WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x0000000719d58fe0> (a java.util.concurrent.FutureTask)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.FutureTask.awaitDone(FutureTask.java:429)
    at java.util.concurrent.FutureTask.get(FutureTask.java:191)
    at ThreadedSortingComparsion.start(ThreadedSortingComparsion.java:48)
    at ThreadedSortingComparsion.main(ThreadedSortingComparsion.java:162)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)

"VM Thread" os_prio=2 tid=0x0000000056348800 nid=0x2984 runnable 

"GC task thread#0 (ParallelGC)" os_prio=0 tid=0x0000000043147000 nid=0x27e0 runnable 

"GC task thread#1 (ParallelGC)" os_prio=0 tid=0x0000000043148800 nid=0x20b4 runnable 

"GC task thread#2 (ParallelGC)" os_prio=0 tid=0x000000004314a000 nid=0x1da4 runnable 

"GC task thread#3 (ParallelGC)" os_prio=0 tid=0x000000004314c000 nid=0x29e0 runnable 

"GC task thread#4 (ParallelGC)" os_prio=0 tid=0x000000004314e000 nid=0xa04 runnable 

"GC task thread#5 (ParallelGC)" os_prio=0 tid=0x0000000043150000 nid=0x14b8 runnable 

"GC task thread#6 (ParallelGC)" os_prio=0 tid=0x0000000043153800 nid=0xf00 runnable 

"GC task thread#7 (ParallelGC)" os_prio=0 tid=0x0000000043154800 nid=0x243c runnable 

"VM Periodic Task Thread" os_prio=2 tid=0x0000000068c82000 nid=0x22d8 waiting on condition 

JNI global references: 224

Heap
 PSYoungGen      total 76288K, used 13755K [0x0000000715580000, 0x000000071aa80000, 0x00000007c0000000)
  eden space 65536K, 4% used [0x0000000715580000,0x0000000715874910,0x0000000719580000)
  from space 10752K, 99% used [0x0000000719580000,0x0000000719ffa348,0x000000071a000000)
  to   space 10752K, 0% used [0x000000071a000000,0x000000071a000000,0x000000071aa80000)
 ParOldGen       total 175104K, used 33211K [0x00000005c0000000, 0x00000005cab00000, 0x0000000715580000)
  object space 175104K, 18% used [0x00000005c0000000,0x00000005c206ed30,0x00000005cab00000)
 Metaspace       used 4277K, capacity 4790K, committed 4992K, reserved 1056768K
  class space    used 484K, capacity 535K, committed 640K, reserved 1048576K

quick sort:     355.579434803s
merge sort:     355.629940032s
insertion sort: 355.532578023s