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JDK-8007003 : ParNew sends the heap summary too early

Details
Type:
Bug
Submit Date:
2013-01-28
Status:
Resolved
Updated Date:
2013-06-14
Project Name:
JDK
Resolved Date:
2013-03-12
Component:
hotspot
OS:
Sub-Component:
gc
CPU:
Priority:
P5
Resolution:
Fixed
Affected Versions:
Fixed Versions:
hs24 (b36)

Related Reports
Backport:

Sub Tasks

Description
If there is a risk for promotion failure then ParNew can decide to do an early exit. In ParNew::collect, the heap summary event is sent before this check, which means that there might be a heap summary without a corresponding garbage collection event.

I = low
L = medium
w = high
-------------------
ILW => P5
                                    

Comments
Could be verified with:
closed/com/oracle/jfr/gc/TestHeapSummaryEventParNewCMS.java
closed/com/oracle/jfr/gc/TestHeapSummaryEventParNewSerial.java


                                     
2013-06-14
URL:   http://hg.openjdk.java.net/hsx/hsx24/hotspot/rev/e41e48824311
User:  jwilhelm
Date:  2013-03-12 18:59:01 +0000

                                     
2013-03-12
The easy fix would be not to count the early exited GC. This would also be the correct fix. Unfortunately this is not a quick fix since the MX beans counts these as GCs (which is a bug in itself). A more correct solution would be something like having should_collect() detecting the promotion failed condition and say no to GC.
                                     
2013-01-30



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