Sorry Ryan, misread the stack trace. The main thread is interacting with the executors LBQ not the application one.
I'll see if I can use this test to reproduce the issue on Monday. David Holmes > -----Original Message----- > From: [email protected] > [mailto:[email protected]]on Behalf Of David > Holmes > Sent: Saturday, 18 July 2009 12:15 PM > To: Ryan Betts; [email protected] > Cc: core-libs-dev > Subject: Re: [concurrency-interest] LinkedBlockingDeque deadlock? (Test > case) > > > > > Ryan, > > Thanks very much for this. > > When this "deadlocks" does top show whether the java process is actually > quiet or is it still consuming CPU? I notice that in the stack > dump the main > thread is in the process of unlocking the lock that the other threads are > waiting upon and hence the system is not deadlocked - unless that main > thread is actually "stuck" somewhere. Can you take a series of > stackdumps to > see if/how the main thread is executing? > > Feel free to just send them to me rather than the mailing lists. > > Thanks, > David Holmes > > > -----Original Message----- > > From: [email protected] > > [mailto:[email protected]]on Behalf Of Ryan > > Betts > > Sent: Saturday, 18 July 2009 2:48 AM > > To: [email protected] > > Cc: core-libs-dev > > Subject: Re: [concurrency-interest] LinkedBlockingDeque deadlock? (Test > > case) > > > > > > Hello all, > > > > I've been working with Ariel on the j.u.c.LinkedBlockingDeque deadlock > > we observe. The attached test case reproduces the deadlock > > intermittently, usually requiring several minutes. The test simply > > prints periods until it deadlocks. Attempts to produce a simpler test > > case using only ReentrantLock or without an ExecutorService were > > unsuccessful. > > > > I've attached jstack reports showing the deadlocked case and the dmesg > > output from one of the servers that reproduces the defect. To date, > > this deadlock only occurs on our 2 socket i7s. > > > > We have not filed a defect with Sun for this issue. If that would be > > helpful (or necessary), we would of course happily oblige. > > > > $ java -version > > java version "1.6.0" > > OpenJDK Runtime Environment (build 1.6.0-b09) > > OpenJDK 64-Bit Server VM (build 1.6.0-b09, mixed mode) > > > > $ uname -a > > Linux host3e 2.6.18-128.1.16.el5 #1 SMP Tue Jun 30 06:07:26 EDT 2009 > > x86_64 x86_64 x86_64 GNU/Linux > > > > $ javac LBDLockPatternTest.java > > $ java LBDLockPatternTest > > > > > > Thank you, > > *--Ryan. > > > > > > > > _______________________________________________ > Concurrency-interest mailing list > [email protected] > http://cs.oswego.edu/mailman/listinfo/concurrency-interest
