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JDK-6924259 : Remove String.count/String.offset/String.hashcode

Details
Type:
Enhancement
Submit Date:
2010-02-08
Status:
Closed
Updated Date:
2017-05-16
Project Name:
JDK
Resolved Date:
2013-07-18
Component:
hotspot
OS:
generic,windows_nt,windows_xp
Sub-Component:
compiler
CPU:
generic,x86
Priority:
P3
Resolution:
Fixed
Affected Versions:
hs17,1.4.0,5.0,6
Fixed Versions:
hs24

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Sub Tasks

Description
Investigate the performance impacts of removing String.count, String.offset,
and String.hashcode on various industry standard benchmarks.
There are no new regression tests for this change because the API is not impacted. It is a behind-the-scenes performance/implementation change only

                                    

Comments
EVALUATION

http://hg.openjdk.java.net/lambda/lambda/hotspot/rev/8f972594effc
                                     
2012-06-29
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-rt/hotspot/rev/8f972594effc
                                     
2012-05-26
EVALUATION

http://hg.openjdk.java.net/hsx/hsx23.2/hotspot/rev/3facbb14e873
                                     
2012-05-23
EVALUATION

http://hg.openjdk.java.net/hsx/hotspot-comp/hotspot/rev/8f972594effc
                                     
2012-05-14
EVALUATION

A working change has been developed that allows a version
of the String class that doesn't use the count/offset fields.
However, it's not possible to eliminate the hashcode field.
This fix also works with compressed strings.

At this point, the fix is on hold as other priorities have
taken precedence.
                                     
2010-11-12



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