On 11/06/2013 1:54 AM, Chris Hegarty wrote:
I'm not sure I ever saw this test fail, but it does look like it has
issues.
I would much prefer to see a j.u.c.Latch/Phaser used to synchronize
across these threads.
I don't think that is possible. The main thread wants to reset the count
after the suspend has been issued by "first", but once the suspend has
been issued the "first" thread can't signal the synchronizer to let the
main thread proceed. The poll around isAlive() does address the main
issue of a slowly starting thread.
For completeness the count variable should be volatile as well.
Cheers,
David
-Chris.
On 10/06/2013 13:51, Ivan Gerasimov wrote:
Hello everyone!
The test of ThreadGroup.Suspend() was reported to fail on rare occasions.
It can happen on a busy machine that 1 second delay would not be enough
for the second thread to start.
Then the first thread would suspend only itself and the test would fail.
Earlier, another test was updated for similar reasons [1], [2].
The proposed test can still report false *positive* results if the
second thread has had no chance to execute during one second after it
had started.
To avoid them there must be a way do distinguish suspended threads.
WEBREV: http://cr.openjdk.java.net/~igerasim/7181748/webrev.0/
BUG: http://bugs.sun.com/view_bug.do?bug_id=7181748
[1] http://bugs.sun.com/view_bug.do?bug_id=7084033
[2] http://hg.openjdk.java.net/jdk8/jdk8/jdk/rev/184578f3e8b9
Sincerely yours,
Ivan Gerasimov
<https://jbs.oracle.com/bugs/browse/JDK-7084033>
