patan_java_benchmark

	public static void main(String[] args) throws InterruptedException {
		benchmark(10, 20000);
		benchmark(100, 20000);
		benchmark(1000, 20000);
		benchmark(10, 200000);
		benchmark(100, 200000);
	}

	private static void benchmark(final int threads, final int itemsPerThread) throws InterruptedException {
		long millis = System.currentTimeMillis();
		subject =  StatisticsFactory.createThreadsafeStatistics();
		final CountDownLatch latch = new CountDownLatch(threads);
		for (int i =0 ; i < threads; i++) {
			new Thread(new Runnable() {
				@Override
				public void run() {
					Stopwatch stopwatch = subject.startStopwatch();
					for (int k =0 ; k < itemsPerThread; k++) {
						subject.addOccurrence("concurrency.counter");
						subject.addSample("concurrency.sample", k);
					}
					subject.recordElapsedTime("concurrency.duration", stopwatch);
					latch.countDown();
				}
			}).start();
		}
		latch.await();
		Snapshot snapshot = subject.getSnapshot();
		assertThat(snapshot.getDurations().get("concurrency.duration").getSampleCount()).isEqualTo(threads);
		assertThat(snapshot.getSamples().get("concurrency.sample").getSampleCount()).isEqualTo(itemsPerThread * threads);
		assertThat(snapshot.getOccurrences().get("concurrency.counter")).isEqualTo(itemsPerThread * threads);
		System.out.println(threads + " threads with " + itemsPerThread + " items takes " + (System.currentTimeMillis() - millis));
	}
  
  //Results:
  //10 threads with 20000 items takes 89 millis
  //100 threads with 20000 items takes 265 millis
  //1000 threads with 20000 items takes 2888 millis  
  //10 threads with 200000 items takes 311 millis
  //100 threads with 200000 items takes 3067 millis