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    <p>@Peter Lawrey</p> <blockquote> <blockquote> <p>Certain operations use OS calls (such as locking/cyclic barriers)</p> </blockquote> </blockquote> <p>Those are NOT OS (kernel) calls. Implemented via simple CAS (which on x86 comes w/ free memory fence as well)</p> <p>One more: dont use ArrayBlockingQueue unless you know why (you use it).</p> <p>@OP: Look at ThreadPoolExecutor, it offers excellent producer/consumer framework.</p> <p><em>Edit below</em>:</p> <p>to reduce the latency (baring the busy wait), change the queue to SynchronousQueue add the following like before starting the consumer</p> <pre><code>... consumerThread.setPriority(Thread.MAX_PRIORITY); consumerThread.start(); </code></pre> <p>This is the best you can get.</p> <hr> <p>Edit2: Here w/ sync. queue. And not printing the results.</p> <pre><code>package t1; import java.math.BigDecimal; import java.util.concurrent.CountDownLatch; import java.util.concurrent.SynchronousQueue; public class QueueTest { static final int RUNS = 250000; final SynchronousQueue&lt;Long&gt; queue = new SynchronousQueue&lt;Long&gt;(); int sleep = 1000; long[] results = new long[0]; public void start(final int runs) throws Exception { results = new long[runs]; final CountDownLatch barrier = new CountDownLatch(1); Thread consumerThread = new Thread(new Runnable() { @Override public void run() { barrier.countDown(); try { for(int i = 0; i &lt; runs; i++) { results[i] = consume(); } } catch (Exception e) { return; } } }); consumerThread.setPriority(Thread.MAX_PRIORITY); consumerThread.start(); barrier.await(); final long sleep = this.sleep; for(int i = 0; i &lt; runs; i++) { try { doProduce(sleep); } catch (Exception e) { return; } } } private void doProduce(final long sleep) throws InterruptedException { produce(); } public void produce() throws InterruptedException { queue.put(new Long(System.nanoTime()));//new Long() is faster than value of } public long consume() throws InterruptedException { long t = queue.take(); long now = System.nanoTime(); return now-t; } public static void main(String[] args) throws Throwable { QueueTest test = new QueueTest(); System.out.println("Starting + warming up..."); // Run first once, ignoring results test.sleep = 0; test.start(15000);//10k is the normal warm-up for -server hotspot // Run again, printing the results System.gc(); System.out.println("Starting again..."); test.sleep = 1000;//ignored now Thread.yield(); test.start(RUNS); long sum = 0; for (long elapsed: test.results){ sum+=elapsed; } BigDecimal elapsed = BigDecimal.valueOf(sum, 3).divide(BigDecimal.valueOf(test.results.length), BigDecimal.ROUND_HALF_UP); System.out.printf("Avg: %1.3f micros%n", elapsed); } } </code></pre>
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