Hotspot: GC "logs" from hell

Bernd Eckenfels bernd-2013 at
Thu May 23 21:48:30 UTC 2013

Am 23.05.2013, 20:56 Uhr, schrieb Jon Masamitsu <jon.masamitsu at>:
> This has been on our to-do list for
> quite a while, but  it seems like every time we try to push it up,
> something new gets dropped on top and pushes it back
> down.

Sure, what I think might be a good strategy is to leverage the event work.  
If I understand it correctly there is already a event ringbuffer for the  
flightrecorder stuff. And if all relevant GC events are pushed (with most  
relevant metrics) to that ring already (for the commercial products) the  
dumping of that buffer to a logfile is a more isolated extension to the  
JVM (as opposed to collecting all gc events which is all over the Hotspot  
gc subsystem).

This should also allow to reduce the diagnostic code (printf formats) all  
over the place.

> If in the end all we can do is provide guidance, is there
> any sentiment in the community to try and get this done
> separate from Oracle?

I would certainly contribute, however my C is very rusty (I do not even  
have a working build environment locally).


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