Request for review (s) - 7198873

Mikael Gerdin mikael.gerdin at
Tue Sep 25 14:23:14 UTC 2012


On 2012-09-24 23:46, Jon Masamitsu wrote:
> NPG: VM Does not unload classes with UseConcMarkSweepGC
> If CMS is not doing class unloading, don't start a concurrent
> collection for classloader (and metadata) collection (since
> it won't happen without class unloading).

It looks like you still unconditionally call expand_and_allocate when 
running with CMS, no matter the value of CMSClassUnloadingEnabled.
I think that the code:

  213       // For CMS expand since the collection is going to be 
  214       _result =
_loader_data->metaspace_non_null()->expand_and_allocate(_size, _mdtype);

Should be inside the "if (CMSClassUnloadingEnabled)" and if running 
without it set then CMS users will have to take the hit of a stw full gc 
when running into the metadata threshold.


> Also, refactored the code for readability and guarded extra
> output with Verbose.
> Thanks.
> Jon

Mikael Gerdin
Java SE VM SQE Stockholm

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