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Missing exception traces

This was an interesting issue.

We were seeing exceptions in log with empty traces, this was happening even though we had done logger.error(e); or e.printStackTrace.

Our CTO found out that aparently its some JVM optimization by sun (now oracle lol).


From http://java.sun.com/j2se/1.5.0/relnotes.html
he found

<<<
The compiler in the server VM now provides correct stack backtraces for all "cold" built-in exceptions. For performance purposes, when such an exception is thrown a few times, the method may be recompiled. After recompilation, the compiler may choose a faster tactic using preallocated exceptions that do not provide a stack trace. To disable completely the use of preallocated exceptions, use this new flag: -XX:-OmitStackTraceInFastThrow.
>>>

Kudos to him as we were thinking its some DWR library issue eating the trace.

Comments

  1. UnknownNovember 1, 2010 at 5:15 AM

    Nice catch. Keep posting such catch-things which roughly I think 95% or Java programmers don't know about, it makes avg developers level higher! :)

    ReplyDelete

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