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Bug ID: 6896099 Integrate CMS heap ergo with default heap sizing ergo
6896099 : Integrate CMS heap ergo with default heap sizing ergo

Details
Type:
Enhancement
Submit Date:
2009-10-28
Status:
Closed
Updated Date:
2011-05-26
Project Name:
JDK
Resolved Date:
2011-04-24
Component:
hotspot
OS:
generic
Sub-Component:
gc
CPU:
x86,generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
hs17
Fixed Versions:
hs21

Related Reports
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Sub Tasks

Description
CMS heap ergo should be integrated with the default heap sizing ergo.  Right now
CMS ergo is a world unto itself.  Default heap sizing should run first, then
CMS should modify it to suit itself.

                                    

Comments
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/dde920245681
                                     
2011-03-25
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-rt/hotspot/rev/dde920245681
                                     
2011-03-21
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/dde920245681
                                     
2011-03-16
PUBLIC COMMENTS

This CR should be release-noted. Doc-writer, please use the following
text, suitably word-smithed to provide suitable verbage in release notes:-

The default out-of-the-box heap size and shape parameters for the
concurrent mark sweep collector (CMS) have been modified to take advantage of
the faster platforms since JDK 6 was released when these settings were
last changed. Like the other collectors in HotSpot, CMS will now use
the available physical memory on the platform to size its heap, while
attempting to shape that heap so as to keep pause times associated with
minor collections "reasonable". The specific shape of the heap may
be platform-dependent in other ways as well. Users can override all or
some of these default settings by means of explicitly sizing or shaping
the heap, aka "heap tuning", to suit their specific needs.

At this point, please point to the heap tuning guide which will also be
updated to describe the default settings for this and other collectors.
                                     
2011-03-15
EVALUATION

High time.
                                     
2010-11-01



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