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Bug ID: JDK-7097048 G1: extend the G1 SA changes to print per-heap space information
JDK-7097048 : G1: extend the G1 SA changes to print per-heap space information

Details
Type:
Bug
Submit Date:
2011-09-30
Status:
Closed
Updated Date:
2013-10-04
Project Name:
JDK
Resolved Date:
2012-01-23
Component:
hotspot
OS:
generic
Sub-Component:
svc
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
hs23
Fixed Versions:
hs23 (b02)

Related Reports
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Sub Tasks

Description
The implementation of G1 support into the SA (7059019) has been inconsistent with what the other GCs do wrt the jmap -heap output. G1 only prints whole heap information whereas the other GCs print per-heap space information. Here's an example. G1:

Heap Usage:
Garbage-First (G1) Heap
   region size = 1048576 (1.0MB)
   regions     = 20
   capacity    = 20971520 (20.0MB)
   used        = 7154320 (6.8228912353515625MB)
   free        = 13817200 (13.177108764648438MB)
   34.11445617675781% used
Perm Generation:
   capacity = 16777216 (16.0MB)
   used     = 2570176 (2.45111083984375MB)
   free     = 14207040 (13.54888916015625MB)
   15.319442749023438% used

ParallelGC:

Heap Usage:
PS Young Generation
Eden Space:
   capacity = 17301504 (16.5MB)
   used     = 14982784 (14.2886962890625MB)
   free     = 2318720 (2.2113037109375MB)
   86.59815932765152% used
From Space:
   capacity = 2883584 (2.75MB)
   used     = 0 (0.0MB)
   free     = 2883584 (2.75MB)
   0.0% used
To Space:
   capacity = 2883584 (2.75MB)
   used     = 0 (0.0MB)
   free     = 2883584 (2.75MB)
   0.0% used
PS Old Generation
   capacity = 44040192 (42.0MB)
   used     = 240248 (0.22911834716796875MB)
   free     = 43799944 (41.77088165283203MB)
   0.5455198742094494% used
PS Perm Generation
   capacity = 16777216 (16.0MB)
   used     = 2574864 (2.4555816650390625MB)
   free     = 14202352 (13.544418334960938MB)
   15.34738540649414% used

We should update the SA so that it can also print the per-heap space information with G1 like ParalleGC and the other GCs.

                                    

Comments
EVALUATION

See main CR
                                     
2011-10-22
SUGGESTED FIX

It turns out this is a relatively easy fix. The changes for 7075646 maintain all the information needed in fields in the G1MonitoringSupport class (these are calculated automatically). So it should be easy to get that information from inside the SA (through a wrapper class).
                                     
2011-09-30
EVALUATION

See Description and Suggested Fix.
                                     
2011-09-30
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-gc/hotspot/rev/81aa07130d30
                                     
2011-10-04
EVALUATION

http://hg.openjdk.java.net/hsx/hsx22/hotspot/rev/aade124d1b1d
                                     
2011-10-12



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