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Bug ID: JDK-6649622 HotSpot Biased locking needs tuning on latest CPUs
JDK-6649622 : HotSpot Biased locking needs tuning on latest CPUs

Details
Type:
Enhancement
Submit Date:
2008-01-11
Status:
Resolved
Updated Date:
2011-02-17
Project Name:
JDK
Resolved Date:
2008-11-19
Component:
hotspot
OS:
solaris_nevada
Sub-Component:
compiler
CPU:
x86
Priority:
P2
Resolution:
Fixed
Affected Versions:
6u4p
Fixed Versions:
hs14 (b07)

Related Reports
Backport:
Backport:

Sub Tasks

Description
HotSpot Biased Locking needs tunign on latest CPUs.

-see comments for details-

                                    

Comments
SUGGESTED FIX

Add to set_aggressive_opts_flags() in arguments.cpp just after the NOT_WINDOWS
disabling of CacheTimeMillis.

  if (FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
    FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
  }

Alternatively, just change the value of BiasedLockingStartupDelay in globals.hpp
to 500.  This is the preferred solution if indeed Alacrity shows no startup time
degradation on client apps as a result of doing so.
                                     
2008-03-20
EVALUATION

Can put pushed to hs13 with AggressiveOpts, perhaps hs14 without.
                                     
2008-06-17
EVALUATION

http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/b6cfd754403d
                                     
2008-10-29



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