Uwe you rock! Beside my morning entertainment this was an awesome job! simon
On Tue, Mar 12, 2013 at 8:31 AM, Tommaso Teofili <tommaso.teof...@gmail.com> wrote: > thanks Uwe! > > > 2013/3/12 Robert Muir <rcm...@gmail.com> >> >> Uwe: Thanks for working with them to get all these issues fixed. >> >> On Mon, Mar 11, 2013 at 7:34 PM, Uwe Schindler <u...@thetaphi.de> wrote: >> > Hi, >> > >> > FYI, Oracle has a fix for the G1GC hang in UIMA waiting for review: >> > >> > Issue: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8009536 >> > Webrev: >> > http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2013-March/006215.html >> > Patch: http://cr.openjdk.java.net/~johnc/8009536/webrev.0/ >> > >> > Thanks to John Cuthbertson and Bengt Rutisson @ Oracle for fixing so >> > fast! We just have to wait for a new JDK8 build with that fix included (and >> > some more for the other Lucene-related bugs). >> > Uwe >> > >> > ----- >> > Uwe Schindler >> > H.-H.-Meier-Allee 63, D-28213 Bremen >> > http://www.thetaphi.de >> > eMail: u...@thetaphi.de >> > >> > >> >> -----Original Message----- >> >> From: Mark Miller [mailto:markrmil...@gmail.com] >> >> Sent: Wednesday, March 06, 2013 7:52 PM >> >> To: dev@lucene.apache.org >> >> Subject: Re: JVM hanging when using G1GC on JDK8 b78 or b79 (Linux 32 >> >> bit) >> >> >> >> Awesome work Uwe! Nice job getting this some attention. >> >> >> >> - mark >> >> >> >> On Mar 6, 2013, at 10:41 AM, Uwe Schindler <u...@thetaphi.de> wrote: >> >> >> >> > It seems that there is already an explanation from the Oracle >> >> > engineer: >> >> > >> >> >> -----Original Message----- >> >> >> From: John Cuthbertson [mailto:john.cuthbert...@oracle.com] >> >> >> Sent: Wednesday, March 06, 2013 7:04 PM >> >> >> To: Thomas Schatzl >> >> >> Cc: Uwe Schindler; hotspot-gc-...@openjdk.java.net; 'David Holmes'; >> >> >> 'Dawid Weiss'; hotspot-...@openjdk.java.net >> >> >> Subject: Re: JVM hanging when using G1GC on JDK8 b78 or b79 (Linux >> >> >> 32 >> >> >> bit) >> >> >> >> >> >> Hi Everyone, >> >> >> >> >> >> All: >> >> >> I've looked at the bug report (haven't tried to reproduce it yet) >> >> >> and >> >> >> Bengt's analysis is correct. The concurrent mark thread is entering >> >> >> the synchronization protocol in a marking step call. That code is >> >> >> waiting for some non-existent workers to terminate before >> >> >> proceeding. >> >> >> Normally we shouldn't be entering that code but I think we >> >> >> overflowed >> >> >> the global marking stack (I updated the CR at ~1am my time with that >> >> >> conjecture). I think I missed a set_phase() call to tell the >> >> >> parallel >> >> >> terminator that we only have one thread and it's picking up the >> >> >> number of workers that executed the remark parallel task. >> >> >> >> >> >> Thomas: you were on the right track with your comment about the >> >> >> marking stack size. >> >> >> >> >> >> David: >> >> >> Thanks for helping out here. The stack trace you mentioned was for >> >> >> one the refinement threads - a concurrent GC thread. When a >> >> >> concurrent GC thread "joins" the suspendible thread set, it means >> >> >> that it will observe and participate in safepoint operations, i.e. >> >> >> the thread will notice that it should reach a safepoint and the >> >> >> safepoint >> >> synchronizer code will wait for it to block. >> >> >> When we wish a concurrent GC thread to not observe safepoints, that >> >> >> thread leaves the suspendible thread set. I think the name could be >> >> >> a >> >> >> bit better and Tony, before he left, had a change that used a scoped >> >> >> object to join and leave the STS that hasn't been integrated yet. >> >> >> IIRC Tony wasn't happy with the name he chose for that also. >> >> >> >> >> >> Uwe: >> >> >> Thanks for bringing this up and my apologies for not replying >> >> >> sooner. >> >> >> I will have a fix fairly soon. If I'm correct about it being caused >> >> >> by overflowing the marking stack you can work around the issue by >> >> >> increasing the MarkStackSize.you could try increasing it to 2M or 4M >> >> >> entries (which is the current max size). >> >> >> >> >> >> Cheers, >> >> >> >> >> >> JohnC >> >> > >> >> > ----- >> >> > Uwe Schindler >> >> > H.-H.-Meier-Allee 63, D-28213 Bremen >> >> > http://www.thetaphi.de >> >> > eMail: u...@thetaphi.de >> >> > >> >> > >> >> >> -----Original Message----- >> >> >> From: Uwe Schindler [mailto:u...@thetaphi.de] >> >> >> Sent: Wednesday, March 06, 2013 1:35 PM >> >> >> To: dev@lucene.apache.org >> >> >> Subject: FW: JVM hanging when using G1GC on JDK8 b78 or b79 (Linux >> >> >> 32 >> >> >> bit) >> >> >> >> >> >> They already understood the G1GC problem with JDK 8 b78/b79 and >> >> >> working on a fix. This was really fast: >> >> >> http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2013- >> >> >> March/006128.html >> >> >> >> >> >> Uwe >> >> >> >> >> >> ----- >> >> >> Uwe Schindler >> >> >> H.-H.-Meier-Allee 63, D-28213 Bremen >> >> >> http://www.thetaphi.de >> >> >> eMail: u...@thetaphi.de >> >> >> >> >> > >> >> > >> >> > >> >> > --------------------------------------------------------------------- >> >> > To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For >> >> > additional commands, e-mail: dev-h...@lucene.apache.org >> >> > >> >> >> >> >> >> --------------------------------------------------------------------- >> >> To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For >> >> additional >> >> commands, e-mail: dev-h...@lucene.apache.org >> > >> > >> > --------------------------------------------------------------------- >> > To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org >> > For additional commands, e-mail: dev-h...@lucene.apache.org >> > >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org >> For additional commands, e-mail: dev-h...@lucene.apache.org >> > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org
