Review Request (7u): JDK-8048271: Minor GC times doubled from JDK 6u35 to JDK 7u51

Poonam Bajaj poonam.bajaj at oracle.com
Mon Jul 14 00:47:37 UTC 2014


Bug: JDK-8048271 <https://bugs.openjdk.java.net/browse/JDK-8048271>: 
Minor GC times doubled from JDK 6u35 to JDK 7u51
Webrev: http://cr.openjdk.java.net/~poonam/8048271/webrev.00/

With JDK7, the minor GC collection times have increased as compared to 
the collection times with JDK6uxx. These pauses have increased due to 
the fact that the Intern strings and the class statics were moved from 
PermGen to the Java Heap in JDK7 and, are collected as part of the minor 
GC collections thus contributing to the increase in GC times.

These changes make the debug flag 'JavaObjectsInPerm' a diagnostic flag 
so that it can be used to revert the PermGen changes in jdk7 and get the 
earlier minor GC pause times.

Testing:
Manual testing comparing the PSYoungGen times with and without 
JavaObjectsInPerm option
JPRT


Thanks,
Poonam


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/attachments/20140714/96697f37/attachment.html>


More information about the hotspot-gc-dev mailing list