United StatesChange Country, Oracle Worldwide Web Sites Communities I am a... I want to...
Bug ID: JDK-7030453 JSR 292 ClassValue.get method is too slow
JDK-7030453 : JSR 292 ClassValue.get method is too slow

Details
Type:
Bug
Submit Date:
2011-03-23
Status:
Resolved
Updated Date:
2013-04-30
Project Name:
JDK
Resolved Date:
2012-01-27
Component:
hotspot
OS:
generic
Sub-Component:
compiler
CPU:
generic
Priority:
P3
Resolution:
Fixed
Affected Versions:
7
Fixed Versions:

Related Reports
Backport:

Sub Tasks

Description
Now that ClassValue is in the java.lang package, it should be co-optimized with Class, just as ThreadLocal is co-optimized with Thread.

                                    

Comments
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-main/jdk/rev/92d2cba30f08

Technical discussion of the fix may be found here:
  http://mail.openjdk.java.net/pipermail/mlvm-dev/2011-September/003930.html

This bug is mainly a performance bug, due to the use of a global table (keyed by Class) instead of a direct link (from a non-public field in Class).  The global table also introduces race conditions, at least potentially, when mapping from a new Class key to a stable root for the Class's ClassValue set.
                                     
2012-01-21



Hardware and Software, Engineered to Work Together