Hi David, Sorry for not getting back earlier. Here's the changes to /jdk8_tl/jdk/test/java/lang/ref/Basic.java that you suggested earlier. -------------------x---------------------
diff -r 16f63a94c231 test/java/lang/ref/Basic.java --- a/test/java/lang/ref/Basic.java Fri Apr 05 18:20:12 2013 -0700 +++ b/test/java/lang/ref/Basic.java Sun Apr 07 00:27:55 2013 +0100 @@ -29,7 +29,7 @@ import java.lang.ref.*; import java.util.Vector; - +import java.util.concurrent.CountDownLatch; public class Basic { @@ -71,10 +71,11 @@ }); } - static void createNoise() throws InterruptedException { + static void createNoise(final CountDownLatch complete) throws InterruptedException { fork(new Runnable() { public void run() { keep.addElement(new PhantomReference(new Object(), q2)); + complete.countDown(); } }); } @@ -101,9 +102,11 @@ for (int i = 1;; i++) { Reference r; - createNoise(); ++ CountDownLatch noiseComplete = new CountDownLatch(1); ++ createNoise(noiseComplete); + System.err.println("GC " + i); - Thread.sleep(10); + noiseComplete.await(); System.gc(); System.runFinalization(); -------------------x--------------------- Its still implemented with CountdownLatch, but as you suggest we implement the above via Semaphore it will have to be the next version from me - CountdownLatch was suggested by many at the TestFest last month but personally I benefit from getting exposed to different techniques. I'll back to you with a solution applied using Semaphore. Cheers, mani On Fri, Apr 5, 2013 at 2:40 AM, David Holmes <david.hol...@oracle.com>wrote: > On 5/04/2013 11:27 AM, Mani Sarkar wrote: > >> Hi David, >> >> I'll reply in more detail later but to respond to your comment on: >> >> > I would not add the extra methods around the cdl.await() and >> cdl.countDown() as they just obscure things >> In general its meant to do the opposite. We come across a lot of code >> that does not express intent, and the purpose of encapsulating such >> blocks (even if its a single line) is to make the flow verbose and >> readable - I have seen similar code-snippets in the Hotspot (C/C++ >> codebase) making it easy to follow what is going on. One of the things I >> picked up from TestFest was to make the tests more legible, logical and >> easy to maintain and scale - it was our intent when we changed this test. >> > > Sorry, createNoiseHasFinishedAddingTo**Keep is certainly verbose but not > readable. This would be much more readable: > > Countdownlatch noiseComplete = new ... > createNoise(noiseComplete); > ... > noiseComplete.await(); > > and: > > static void createNoise(final CountDownLatch complete) throws > InterruptedException { > ... > complete.countDown(); > } > > just giving the latch a meaningful name is sufficient to convey intent. > > Note: in this example a Semaphore is probably a better choice than a > CountDownLatch. > > Cheers, > David > > I'll come back with responses for your other comments. >> >> Cheers >> mani >> > -- *Twitter:* @theNeomatrix369 *Blog:* http://neomatrix369.wordpress.com *JUG activity:* LJC Advocate (@adoptopenjdk & @adoptajsr programs) *Meet-a-Project:* https://github.com/MutabilityDetector *Devoxx UK 2013 was a grand success:* http://www.devoxx.com/display/UK13/Home *Don't chase success, rather aim for "Excellence", and success will come chasing after you!*