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
