CMS option for Java7 ignored (was Re: 1.7 G1GC significantly slower than 1.6 Mark and Sweep?)

[Y. Srinivas Ramakrishna]

John, You brought up several related but somewhat orthogonal issues,
so best to deal with each in a separate sub-thread of the
main thread.

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

and also

% 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.

-- ramki