CMS option for Java7 ignored (was Re: 1.7 G1GC significantly slower than 1.6 Mark and Sweep?)
Y. Srinivas Ramakrishna
y.s.ramakrishna at oracle.com
Fri Apr 29 12:57:46 PDT 2011
John, You brought up several related but somewhat orthogonal issues,
so best to deal with each in a separate sub-thread of the
On 4/29/2011 12:23 AM, John Hendrikx wrote:
> .... I don't know how to activate CMS for Java 7, it ignores the option that I'd use
> for Java 6.
> Java6: -ea -Xms256M -Xmx256M -XX:UseConcMarkSweepGC -verbose:gc
>>>>> For 1.6.0_22: -Xms256M -Xmx256M -XX:+UseConcMarkSweepGC
Are you saying that if you do:
-Xms256M -Xmx256M -XX:UseConcMarkSweepGC -verbose:gc
you do not get CMS? If not, what does the GC log say?
Can you provide the following details:
% java -version
% jinfo <pid>
as well as:
% jnifo -flag UseConcMarkSweepGC <pid>
where <pid> is yr JVM process.
The main issue will be dealt with in the original thread.
Sorry for the digression.
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