JEP 173: Remove Rarely-Used Combinations of Garbage Collectors

Jon Masamitsu jon.masamitsu at
Mon Dec 17 18:38:34 UTC 2012

-XX:+UseParNewGC  will give you a parallel young gen collector
plus the serial old gen collector.   It does not have all the features
that -XX:+UseParallelGC has (for example, does not have support
for -XX:+UseNUMA).   It actually is one of the combinations that
we would like to remove.


On 12/14/2012 9:24 PM, lordpixel at wrote:
> For whatever reason I assumed this was only a collector for the young generation... is that wrong? Even if it does give memory back, for one of my apps at least its the old generation that needs to shrink.
> On Dec 14, 2012, at 10:52 AM, Jon Masamitsu<jon.masamitsu at>  wrote:
>> -XX:+UseParNewGC
> AndyT (lordpixel - the cat who walks through walls)
> A little bigger on the inside
> 	(see you later space cowboy, you can't take the sky from me)

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