hsperfdata causing long GC/safepoint times: Don't use mmap?

Evan Jones ejones at twitter.com
Thu Mar 26 21:09:38 UTC 2015

On Thu, Mar 26, 2015 at 11:33 AM, Mikael Gerdin <mikael.gerdin at oracle.com>
> Have the VM asynchronously update the values in the hsperfdata file by
> caching the new values somewhere in memory and using the ServiceThread to
> commit the updated values to the mmaped perf data?

This approach could work, but wouldn't it have to be a native thread? I
thought the ServiceThread is actually a Java thread, so it needs to reach
safepoints with all the others? It seems reasonable to have the statistics
in private memory, periodically written out to /tmp by some other JVM

Thanks for filing the bug!

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