JDK-6649622 : HotSpot Biased locking needs tuning on latest CPUs
Type:Enhancement
Component:hotspot
Sub-Component:compiler
Affected Version:6u4p
Priority:P2
Status:Resolved
Resolution:Fixed
OS:solaris_nevada
CPU:x86
Submitted:2008-01-11
Updated:2011-02-17
Resolved:2008-11-19
The Version table provides details related to the release that this issue/RFE will be addressed.
Unresolved : Release in which this issue/RFE will be addressed. Resolved: Release in which this issue/RFE has been resolved. Fixed : Release in which this issue/RFE has been fixed. The release containing this fix may be available for download as an Early Access Release or a General Availability Release.
EVALUATION
Can put pushed to hs13 with AggressiveOpts, perhaps hs14 without.
17-06-2008
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.