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import java.util.*; |
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import java.util.concurrent.*; |
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import java.util.concurrent.locks.*; |
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import java.util.concurrent.atomic.*; |
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public class ConcurrentQueueLoops { |
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static final ExecutorService pool = Executors.newCachedThreadPool(); |
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static AtomicInteger totalItems; |
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static boolean print = false; |
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static final Integer even = new Integer(42); |
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static final Integer odd = new Integer(17); |
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static int workMask; |
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static final long RUN_TIME_NANOS = 5 * 1000L * 1000L * 1000L; |
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|
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public static void main(String[] args) throws Exception { |
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int maxStages = 8; |
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int items = 100000; |
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|
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> |
int maxStages = 48; |
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int work = 32; |
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Class klass = null; |
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if (args.length > 0) { |
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try { |
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throw new RuntimeException("Class " + args[0] + " not found."); |
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} |
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} |
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else |
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klass = java.util.concurrent.ConcurrentLinkedQueue.class; |
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|
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if (args.length > 1) |
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maxStages = Integer.parseInt(args[1]); |
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|
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if (args.length > 2) |
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work = Integer.parseInt(args[2]); |
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|
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workMask = work - 1; |
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System.out.print("Class: " + klass.getName()); |
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System.out.println(" stages: " + maxStages); |
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System.out.print(" stages: " + maxStages); |
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System.out.println(" work: " + work); |
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|
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print = false; |
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System.out.println("Warmup..."); |
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oneRun(klass, 1, items); |
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oneRun(klass, 4); |
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Thread.sleep(100); |
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oneRun(klass, 1, items); |
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oneRun(klass, 1); |
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Thread.sleep(100); |
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print = true; |
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|
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for (int i = 1; i <= maxStages; i += (i+1) >>> 1) { |
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oneRun(klass, i, items); |
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> |
int k = 1; |
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> |
for (int i = 1; i <= maxStages;) { |
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> |
oneRun(klass, i); |
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> |
if (i == k) { |
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> |
k = i << 1; |
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> |
i = i + (i >>> 1); |
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> |
} |
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> |
else |
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> |
i = k; |
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} |
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pool.shutdown(); |
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} |
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|
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< |
static class Stage implements Callable<Integer> { |
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> |
static final class Stage implements Callable<Integer> { |
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final Queue<Integer> queue; |
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final CyclicBarrier barrier; |
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< |
int items; |
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< |
Stage (Queue<Integer> q, CyclicBarrier b, int items) { |
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> |
Stage (Queue<Integer> q, CyclicBarrier b) { |
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queue = q; |
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barrier = b; |
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< |
this.items = items; |
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> |
} |
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> |
|
| 79 |
> |
static int compute127(int l) { |
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> |
l = LoopHelpers.compute1(l); |
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> |
l = LoopHelpers.compute2(l); |
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> |
l = LoopHelpers.compute3(l); |
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> |
l = LoopHelpers.compute4(l); |
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> |
l = LoopHelpers.compute5(l); |
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> |
l = LoopHelpers.compute6(l); |
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> |
return l; |
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> |
} |
| 88 |
> |
|
| 89 |
> |
static int compute(int l) { |
| 90 |
> |
if (l == 0) |
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> |
return (int)System.nanoTime(); |
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> |
int nn = l & workMask; |
| 93 |
> |
while (nn-- > 0) |
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> |
l = compute127(l); |
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> |
return l; |
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} |
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|
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public Integer call() { |
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// Repeatedly take something from queue if possible, |
| 70 |
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// transform it, and put back in. |
| 99 |
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try { |
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barrier.await(); |
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< |
int l = (int)System.nanoTime(); |
| 101 |
> |
long now = System.nanoTime(); |
| 102 |
> |
long stopTime = now + RUN_TIME_NANOS; |
| 103 |
> |
int l = (int)now; |
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int takes = 0; |
| 105 |
< |
int seq = l; |
| 105 |
> |
int misses = 0; |
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for (;;) { |
| 107 |
+ |
l = compute(l); |
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Integer item = queue.poll(); |
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if (item != null) { |
| 110 |
+ |
l += item.intValue(); |
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++takes; |
| 112 |
< |
l = LoopHelpers.compute2(item.intValue()); |
| 113 |
< |
} |
| 82 |
< |
else if (takes != 0) { |
| 83 |
< |
totalItems.getAndAdd(-takes); |
| 84 |
< |
takes = 0; |
| 85 |
< |
} |
| 86 |
< |
else if (totalItems.get() <= 0) |
| 112 |
> |
} else if ((misses++ & 255) == 0 && |
| 113 |
> |
System.nanoTime() >= stopTime) { |
| 114 |
|
break; |
| 115 |
< |
l = LoopHelpers.compute1(l); |
| 116 |
< |
if (items > 0) { |
| 117 |
< |
--items; |
| 91 |
< |
while (!queue.offer(new Integer(l^seq++))) ; |
| 115 |
> |
} else { |
| 116 |
> |
Integer a = ((l++ & 4)== 0)? even : odd; |
| 117 |
> |
queue.add(a); |
| 118 |
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} |
| 93 |
– |
else if ( (l & (3 << 5)) == 0) // spinwait |
| 94 |
– |
Thread.sleep(1); |
| 119 |
|
} |
| 120 |
< |
return new Integer(l); |
| 120 |
> |
return new Integer(takes); |
| 121 |
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} |
| 122 |
|
catch (Exception ie) { |
| 123 |
|
ie.printStackTrace(); |
| 126 |
|
} |
| 127 |
|
} |
| 128 |
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|
| 129 |
< |
static void oneRun(Class klass, int n, int items) throws Exception { |
| 129 |
> |
static void oneRun(Class klass, int n) throws Exception { |
| 130 |
|
Queue<Integer> q = (Queue<Integer>)klass.newInstance(); |
| 131 |
|
LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer(); |
| 132 |
|
CyclicBarrier barrier = new CyclicBarrier(n + 1, timer); |
| 109 |
– |
totalItems = new AtomicInteger(n * items); |
| 133 |
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ArrayList<Future<Integer>> results = new ArrayList<Future<Integer>>(n); |
| 134 |
|
for (int i = 0; i < n; ++i) |
| 135 |
< |
results.add(pool.submit(new Stage(q, barrier, items))); |
| 135 |
> |
results.add(pool.submit(new Stage(q, barrier))); |
| 136 |
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|
| 137 |
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if (print) |
| 138 |
|
System.out.print("Threads: " + n + "\t:"); |
| 145 |
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} |
| 146 |
|
long endTime = System.nanoTime(); |
| 147 |
|
long time = endTime - timer.startTime; |
| 148 |
+ |
long tpi = time / total; |
| 149 |
|
if (print) |
| 150 |
< |
System.out.println(LoopHelpers.rightJustify(time / (items * n)) + " ns per item"); |
| 127 |
< |
if (total == 0) // avoid overoptimization |
| 128 |
< |
System.out.println("useless result: " + total); |
| 150 |
> |
System.out.println(LoopHelpers.rightJustify(tpi) + " ns per item"); |
| 151 |
|
|
| 152 |
|
} |
| 153 |
+ |
|
| 154 |
|
} |
