Subject:
Re: Fwd: J2SE 5.0 hprof & UseConcMarkSweepGC
From:
Alan Bateman <###@###.###>
Date:
Tue, 23 Nov 2004 20:50:28 +0000
To:
###@###.###

To:
###@###.###
CC:
Y Srinivas Ramakrishna <###@###.###>, ###@###.###


Matt,

Prior to JDK5.0 the JVMPI-based HPROF only worked with the serial collector. In JDK5.0 things have improved and the new JVM TI-based HPROF works with all collectors except for CMS. This is a temporary issue meaning that we will address it at some one (hopefully mustang if there is time). So if you want to use HPROF to do heap/space profiling then you need to run the application without -XX:+UseConcMarkSweepGC. In technical terms the issue relates to the object tagging feature in JVM TI. To get the object tagging feature the agent (HPROF in this case) trys to enable a capability called "can_tag_objects". When CMS is enabled we don't allow an agent to get this capability so the agent gets an error. In the case of HPROF this is the error it prints.

-Alan.

Y Srinivas Ramakrishna wrote:

> ...forwarded from java_sustaining_chat...
>
> Please respond to original posting in case
> you have any information on hprof support
> (current or planned future support) with
> the non-serial collectors, in general, and
> CMS, in particular.
>
> thanks.
> -- ramki.
>
>
>
> ------------------------------------------------------------------------
>
> Subject:
> J2SE 5.0 hprof & UseConcMarkSweepGC
> From:
> Matt Hosanee - Sun Microsystems <###@###.###>
> Date:
> Tue, 23 Nov 2004 17:32:06 +0000
> To:
> ###@###.###
>
> To:
> ###@###.###
>
>
>
> Hi all!
>
> IHAC trying to run this on Solaris SPARC 9/10, J2SE 5.0 GA
>
> bash-2.05b$ java -Xrunhprof -XX:+UseConcMarkSweepGC
>
> but he and I get the following error:
>
> HPROF ERROR: Unable to get necessary JVMTI capabilities. [../../../src/share/demo/jvmti/hprof/hprof_util.c:1182]
>
>
> Would anyone know the state of our support for concurrent mark-sweep GC & hprof?
>
>
> Thanks in advance,
> Matt.


###@###.### 2005-05-31 11:49:11 GMT