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Bug ID: JDK-6923991 G1: improve scalability of RSet scanning
JDK-6923991 : G1: improve scalability of RSet scanning

Details
Type:
Bug
Submit Date:
2010-02-05
Status:
Resolved
Updated Date:
2010-04-03
Project Name:
JDK
Resolved Date:
2010-03-02
Component:
hotspot
OS:
generic
Sub-Component:
gc
CPU:
generic
Priority:
P2
Resolution:
Fixed
Affected Versions:
hs16
Fixed Versions:
hs17 (b10)

Related Reports
Backport:
Backport:
Relates:

Sub Tasks

Description
G1 shows poor load balancing and high contention behavior during RSet scanning on CMT machines as well as on many-core x86. Previously implemented exponential skipping has unacceptable performance when it comes to extremely large processor count.

                                    

Comments
SUGGESTED FIX

The fix would be to implement block-based work stealing in rset scanning phase. It is also required to get rid of copying during this phase and postpone it until the main copying phase. This would also get rid of the buffering that significaly contributes to the observed imbalance.
                                     
2010-02-05
EVALUATION

See Description / Suggested Fix.
                                     
2010-02-11
EVALUATION

ChangeSet=http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/0414c1049f15,ChangeRequest=6923991
                                     
2010-02-12



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