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Bug ID: JDK-7017124 Fix some VM stats to avoid 32-bit overflow
JDK-7017124 : Fix some VM stats to avoid 32-bit overflow

Details
Type:
Bug
Submit Date:
2011-02-03
Status:
Closed
Updated Date:
2011-04-24
Project Name:
JDK
Resolved Date:
2011-04-24
Component:
hotspot
OS:
solaris_10
Sub-Component:
runtime
CPU:
sparc
Priority:
P4
Resolution:
Fixed
Affected Versions:
hs19
Fixed Versions:
hs21 (b03)

Related Reports
Backport:
Relates:

Sub Tasks

Description
During long enough time (tens minutes) on modern processors some VM statistic 32-bit values overflow. We need to use longs. And when a value is long we still have a problem since it is incremented not atomically in 32-bit VM.

                                    

Comments
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/f7de3327c683
                                     
2011-02-08
PUBLIC COMMENTS

During long enough time (tens minutes) on modern processors
some VM statistic 32-bit values overflow. We need to use longs.
And when a value is long we still have a problem since it is
incremented not atomically in 32-bit VM.

Added new method inc_stat_counter() to increment long
statistic values and use atomic long load and store.

Fixed several output formats to use FORMAT macros.

I have to remove v9 check assert from Atomic_move_long() since
it is called before VM_Version is initialized and C2 is built
for v9 only anyway.

I fixed only statistic which was interesting to me.
                                     
2011-02-08



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