RFR: 8227269: Slow class loading when running JVM in debug mode

[Chris Plummer]

Hi Roman,

I'll have a look at this, although it might not be for a few days. In 
the meantime, maybe you can describe your new implementation in 
classTrack.c so it's easier to look through the changes.

thanks,

Chris

On 12/18/19 5:05 AM, Roman Kennke wrote:
> Hello all,
>
> Issue:
> https://bugs.openjdk.java.net/browse/JDK-8227269
>
> I am proposing what amounts to a rewrite of classTrack.c. It avoids 
> throwing away the class cache on GC, and instead keeps track of 
> loaded/unloaded classes one-by-one.
>
> In addition to that, it avoids this whole dance until an agent 
> registers interest in EI_GC_FINISH.
>
> Webrev:
> http://cr.openjdk.java.net/~rkennke/JDK-8227269/webrev.01/
>
> Testing: manual testing of provided test scenarios and timing.
>
> Eg with the testcase provided here:
> https://bugzilla.redhat.com/show_bug.cgi?id=1751985
>
> I am getting those numbers:
> unpatched: no debug: 84s with debug: 225s
> patched:   no debug: 85s with debug: 95s
>
> I also tested successfully through jdk/submit repo
>
> Can I please get a review?
>
> Thanks,
> Roman
>