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Bug ID: JDK-6753547 NUMA allocator: Invalid chunk size computation during adaptive resizing
JDK-6753547 : NUMA allocator: Invalid chunk size computation during adaptive resizing

Details
Type:
Bug
Submit Date:
2008-09-28
Status:
Resolved
Updated Date:
2010-04-03
Project Name:
JDK
Resolved Date:
2008-11-04
Component:
hotspot
OS:
generic
Sub-Component:
gc
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
hs14
Fixed Versions:
hs14 (b06)

Related Reports
Backport:
Backport:

Sub Tasks

Description
The per-lgrp chuck size can be incorrectly computed because of the non-associativity of the floating point operations:

Expression z = x1 * y / x2 with x1 <= x2 can yield z > y, which applied to chunk size computation can result in a chunk size bigger that available.

                                    

Comments
SUGGESTED FIX

Rearrange operations, so that the precision is not lost: z = x1 / x2 * y;
                                     
2008-09-28
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-gc/hotspot/rev/ab4a7734b9c4
                                     
2008-10-07



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