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Bug ID: JDK-6783381 NUMA allocator: don't pretouch eden space with UseNUMA
JDK-6783381 : NUMA allocator: don't pretouch eden space with UseNUMA

Details
Type:
Enhancement
Submit Date:
2008-12-10
Status:
Resolved
Updated Date:
2010-04-03
Project Name:
JDK
Resolved Date:
2009-02-11
Component:
hotspot
OS:
generic
Sub-Component:
gc
CPU:
generic
Priority:
P4
Resolution:
Fixed
Affected Versions:
hs14
Fixed Versions:
hs15 (b01)

Related Reports
Backport:
Backport:

Sub Tasks

Description
With +AlwaysPreTouch and +UseNUMA the space that will be occupied by eden is first pretouched and then all the pages a uncommitted when the NUMA-aware allocator initialized essentially discarding the work.

                                    

Comments
SUGGESTED FIX

Move pretouching into MutableSpace and do the work for each of the spaces separately.
Also make from,to and old spaces interleaved -- as demonstrated by John Coomes that adds about 5% to specjbb performance. Maintain interleaving during resizing, while limiting the amount of work done per GC cycle.
                                     
2008-12-10
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/4e400c36026f
                                     
2009-01-28



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