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Bug ID: JDK-6818524 G1: use ergonomic resizing of PLABs
JDK-6818524 : G1: use ergonomic resizing of PLABs

Details
Type:
Enhancement
Submit Date:
2009-03-17
Status:
Closed
Updated Date:
2013-07-18
Project Name:
JDK
Resolved Date:
2012-08-27
Component:
hotspot
OS:
generic
Sub-Component:
gc
CPU:
generic
Priority:
P4
Resolution:
Fixed
Affected Versions:
hs15
Fixed Versions:
hs24 (b21)

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Sub Tasks

Description
Right now, G1 uses fixed size PLABs for allocation during GC (set by the imaginatively-named parameter -XX:ParallelGCG1AllocBufferSize). It'd be nice to do what CMS does and use dynamic ergonomic resizing of the PLABs.

                                    

Comments
EVALUATION

Performance anomalies being currently investigated.
                                     
2010-09-08
PUBLIC COMMENTS

This might have dependency on 6722568, as if PLABs are very large and appear as a single allocation to the BOT might impose a non-trivial scanning overhead which might cancel out any benefits we'll get out of using large PLABs in the first place.
                                     
2011-08-12
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-gc/hotspot/rev/aaf61e68b255
                                     
2012-08-06



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