https://bugs.eclipse.org/bugs/show_bug.cgi?id=449791
On 18/11/2014 14:06, "Marcus Lagergren" <marcus.lagerg...@oracle.com> wrote: >Nicely done, Duncan. Do you have a link to the issue report? > >Regards >Marcus > >> On 03 Nov 2014, at 16:48, MacGregor, Duncan (GE Energy Management) >><duncan.macgre...@ge.com> wrote: >> >> I’ve reported an Eclipse bug. Doesn’t look like their debugger has ever >> done quite the right thing, unless the behaviour of the JVM has changed >> significantly. >> >> On 03/11/2014 15:33, "Christian Thalinger" >> <christian.thalin...@oracle.com> wrote: >> >>> Interesting. Thanks for digging deep. >>> >>>> On Oct 31, 2014, at 8:36 AM, MacGregor, Duncan (GE Energy Management) >>>> <duncan.macgre...@ge.com> wrote: >>>> >>>> Okay, I now know why the JVM is stuck for so long, just not why >>>>Eclipse >>>> is >>>> doing what it does. >>>> >>>> At certain points during the loading of our application Eclipse will >>>> make >>>> a large number (upto 10000) jdwp classesForSignature requests, each of >>>> which causes the jdwp lib to trawl over a large number of classes >>>> (several >>>> 10s of thousands), resulting in upto a couple hundred million jvmti >>>> GetClassSignature calls, and is particularly pointless because it >>>>fails >>>> to >>>> find any of these classes. >>>> >>>> That last bit gave me a clue. These large numbers of >>>>classesForSignature >>>> requests occur when classes have been GCed, and a request is being >>>> issued >>>> for every single class that has been successfully Gced. Since we¹re >>>> careful to ensure that all the code we dynamically execute at startup >>>>is >>>> done in temporary class loaders so that the everything can be Gced >>>>away, >>>> and since variance LF stuff can also be Gced, the problem is much >>>>worse >>>> than it would be in other applications. >>>> >>>> It¹s really bad in earlier 8 updates without the LF editor work >>>>because >>>> there¹s more classes and more getting Gced, so I¹ve seen 3 minute long >>>> pauses with that version. >>>> >>>> I guess this should be reported as a bug to the Eclipse debug team, >>>>but >>>> I >>>> wonder if classesForSignature can¹t be made faster in some way. >>>> >>>> Regards, Duncan. >>>> >>>> _______________________________________________ >>>> mlvm-dev mailing list >>>> mlvm-dev@openjdk.java.net >>>> http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev >>> >>> _______________________________________________ >>> mlvm-dev mailing list >>> mlvm-dev@openjdk.java.net >>> http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev >> >> _______________________________________________ >> mlvm-dev mailing list >> mlvm-dev@openjdk.java.net >> http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev > >_______________________________________________ >mlvm-dev mailing list >mlvm-dev@openjdk.java.net >http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev _______________________________________________ mlvm-dev mailing list mlvm-dev@openjdk.java.net http://mail.openjdk.java.net/mailman/listinfo/mlvm-dev
