RFR: (S): 8142935: Adding old gen regions does not consider available free space

Tom Benson tom.benson at oracle.com
Fri Mar 18 20:04:59 UTC 2016


Hi,
Please review this G1 change to consider available space before adding 
old gen regions for mixed GCs.  The live_bytes per region are 
accumulated as the cset is built and checked before adding old regions.  
The 'safety_factor' computation previously used only for young regions 
is split out to be shared.

JBS: https://bugs.openjdk.java.net/browse/JDK-8142935 
<https://bugs.openjdk.java.net/browse/JDK-8142935>
Webrev: http://cr.openjdk.java.net/~tbenson/8142935 
<https://bugs.openjdk.java.net/browse/JDK-8142935>/webrev/
Testing: JPRT and hotspot and gc tests.  A targeted test that showed 
evacuation failures due to too many old regions in the cset no longer 
gets them. Some SPECjvm tests with stressful heap/thread settings showed 
better behavior as well.  Normal Perf testing showed no significant 
difference.

Thanks,
Tom
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/attachments/20160318/dfba846b/attachment.html>


More information about the hotspot-gc-dev mailing list