public static void main(String[] args) throws Exception {
ForkJoinPool pool = new ForkJoinPool();
// 提交可分解的PrintTask任务
pool.submit(new PrintTask(0, 600));
pool.awaitTermination(2, TimeUnit.SECONDS);
// 关闭线程池
pool.shutdown();
}
/**
* This method is required to be public, but should never be called explicitly. It performs the
* main run loop to execute {@link ForkJoinTask}s.
*/
public void run() {
Throwable exception = null;
try {
onStart();
pool.runWorker(workQueue);
} catch (Throwable ex) {
exception = ex;
} finally {
try {
onTermination(exception);
} catch (Throwable ex) {
if (exception == null) exception = ex;
} finally {
pool.deregisterWorker(this, exception);
}
}
}
static void test(ForkJoinPool pool, int num) throws Exception {
int ps = pool.getParallelism();
long start = System.nanoTime();
DynamicFib f = new DynamicFib(num);
pool.invoke(f);
long time = System.nanoTime() - start;
double secs = ((double) time) / NPS;
long result = f.number;
System.out.print("DynamicFib " + num + " = " + result);
System.out.printf("\tTime: %9.3f", secs);
long sc = pool.getStealCount();
long ns = sc - lastStealCount;
lastStealCount = sc;
System.out.printf(" Steals: %4d", ns / ps);
System.out.printf(" Workers: %4d", pool.getPoolSize());
System.out.println();
}
public static void main(String[] args) throws Exception {
procs = 0;
int num = 45;
try {
if (args.length > 0) procs = Integer.parseInt(args[0]);
if (args.length > 1) num = Integer.parseInt(args[1]);
} catch (Exception e) {
System.out.println("Usage: java DynamicFib <threads> <number>");
return;
}
for (int reps = 0; reps < 2; ++reps) {
ForkJoinPool pool = (procs == 0) ? new ForkJoinPool() : new ForkJoinPool(procs);
for (int i = 0; i < 20; ++i) test(pool, num);
System.out.println(pool);
pool.shutdown();
}
}
public static void main(String args[]) {
int pLevel;
int threshold;
if (args.length != 2) {
System.out.println("Usage: FJExperiment threshold parallism");
return;
}
pLevel = Integer.parseInt(args[0]);
threshold = Integer.parseInt(args[1]);
// These variables are used to time the task.
long beginT, endT;
// Create a task pool. Notice that the parallelsim level is set.
ForkJoinPool fjp = new ForkJoinPool(pLevel);
double[] nums = new double[1000000];
for (int i = 0; i < nums.length; i++) nums[i] = (double) i;
Transform task = new Transform(nums, 0, nums.length, threshold);
// Starting timing.
beginT = System.nanoTime();
// Start the main ForkJoinTask.
fjp.invoke(task);
// End timing.
endT = System.nanoTime();
System.out.println("Level of parallelism: " + pLevel);
System.out.println("Sequential threshold: " + threshold);
System.out.println("Elapsed time: " + (endT - beginT) + " ns");
System.out.println();
}
/**
* Creates a ForkJoinWorkerThread operating in the given pool.
*
* @param pool the pool this thread works in
* @throws NullPointerException if pool is null
*/
protected ForkJoinWorkerThread(ForkJoinPool pool) {
// Use a placeholder until a useful name can be set in registerWorker
super("aForkJoinWorkerThread");
this.pool = pool;
this.workQueue = pool.registerWorker(this);
}
public static void main(String[] args) throws Exception {
int n = 1 << 18;
int reps = 1 << 8;
Rand[] array = new Rand[n];
for (int i = 0; i < n; ++i) array[i] = new Rand(i + 1);
ForkJoinPool fjp = new ForkJoinPool(1);
ParallelArray<Rand> pa = ParallelArray.createUsingHandoff(array, fjp);
final GetNext getNext = new GetNext();
final Accum accum = new Accum();
final Long zero = Long.valueOf(0);
long last, now;
double elapsed;
for (int j = 0; j < 2; ++j) {
long rseed = rng.nextLong();
resetSeeds(array, rseed);
long seqsum = 0;
last = System.nanoTime();
for (int k = 0; k < reps; ++k) {
seqsum += seqMapReduce(array, getNext, accum, zero);
Rand tmp = array[k];
array[k] = array[n - k - 1];
array[n - k - 1] = tmp;
}
now = System.nanoTime();
elapsed = (double) (now - last) / NPS;
last = now;
System.out.printf("sequential: %7.3f\n", elapsed);
for (int i = 2; i <= NCPU; i <<= 1) {
resetSeeds(array, rseed);
long sum = 0;
fjp.setPoolSize(i);
last = System.nanoTime();
for (int k = 0; k < reps; ++k) {
sum += pa.withMapping(getNext).reduce(accum, zero);
Rand tmp = array[k];
array[k] = array[n - k - 1];
array[n - k - 1] = tmp;
}
now = System.nanoTime();
elapsed = (double) (now - last) / NPS;
last = now;
System.out.printf("poolSize %3d: %7.3f\n", i, elapsed);
if (sum != seqsum) throw new Error("checksum");
}
for (int i = NCPU; i >= 1; i >>>= 1) {
resetSeeds(array, rseed);
long sum = 0;
fjp.setPoolSize(i);
last = System.nanoTime();
for (int k = 0; k < reps; ++k) {
sum += pa.withMapping(getNext).reduce(accum, zero);
Rand tmp = array[k];
array[k] = array[n - k - 1];
array[n - k - 1] = tmp;
}
now = System.nanoTime();
elapsed = (double) (now - last) / NPS;
last = now;
System.out.printf("poolSize %3d: %7.3f\n", i, elapsed);
if (sum != seqsum) throw new Error("checksum");
}
}
fjp.shutdownNow();
fjp.awaitTermination(1, TimeUnit.SECONDS);
Thread.sleep(100);
}
Long countOccurrencesInParallel(Folder folder, String searchedWord) {
return forkJoinPool.invoke(new FolderSearchTask(folder, searchedWord));
}
