JVM freeze

We had our second freeze for today. Without warning, Wildfire 3.2.2 stops doing anything. When trying to create a stackdump with kill -3, we get a dump full of this:

Error occurred during stack walking:
sun.jvm.hotspot.utilities.AssertionFailure: Only used on C2 x86
     at sun.jvm.hotspot.utilities.Assert.that(Assert.java:15)
     at sun.jvm.hotspot.code.CodeBlob.getLinkOffset(CodeBlob.java:193)
     at sun.jvm.hotspot.runtime.amd64.AMD64Frame.senderForCompiledFrame(AMD64Frame.java:297)
     at sun.jvm.hotspot.runtime.amd64.AMD64Frame.sender(AMD64Frame.java:213)
     at sun.jvm.hotspot.runtime.Frame.sender(Frame.java:184)
     at sun.jvm.hotspot.runtime.Frame.realSender(Frame.java:191)
     at sun.jvm.hotspot.runtime.VFrame.sender(VFrame.java:102)
     at sun.jvm.hotspot.runtime.VFrame.javaSender(VFrame.java:129)
     at sun.jvm.hotspot.tools.StackTrace.run(StackTrace.java:50)
     at sun.jvm.hotspot.tools.JStack.run(JStack.java:41)
     at sun.jvm.hotspot.tools.Tool.start(Tool.java:204)
     at sun.jvm.hotspot.tools.JStack.main(JStack.java:58)

The entire dump is attached to this comment.

Killing Wildfire required a kill -9, as the -6 that I usually use didn’'t do anything.

Does anyone have any idea what might cause the JVM to freeze like this? We didn’'t change anything on the running configuration of the server in the last week. Why did it start freezing on us since this morning then?

Message was edited by: Guus (Stackdump removed, see next post)

Followup: The stack dump was not created by a ‘‘kill -3’’ as I initially reported (sorry for that). Instead, the jstack command was being used. This command generates this kind of errors even if the JVM is running fine, so the stack that I originally included to this thread is of no use.

Applying kill -3 to the process while it was unresponsive did not return anything. Sadly, this still does not explain why the JVM froze in the first place. Any ideas?

Hi Guus,

is the JVM freezes there’'s little you can do. Try to use another JVM may help a lot.

If you have debug experience you may want to attach a debugger or create a core file and send it to Sun.

LG

Hi LG,

That’‘s what we figured as well. We moved up our scheduled migration to Java 6 (migrating as we, ehh, type). We’'re hoping that his solves the issue. It would be nice to know what causes it though.

Hey Guus,

I agree with you. Since you were not running latest Java 5 version I think it was wise to update to latest Java version (in your case version 6). A never saw a complete freeze of a JVM (without a crash). Lets hope that moving to latest Java version would help this issue. Are you also using latest OS patches?

Regards,

– Gato

I’‘ll check for the OS patches, I’‘m not sure if our sysadmin did that. As we’‘re not able to reproduce, and the problem seems to have disappeared, I’'ll leave it at that. Thanks all.