[mpich-discuss] Logging MPI Collectives

[sanath kumar]

Oh great. I understand them now. My requirement is to profile MPI benchmark
programs(that typically are very huge). So, from your explanation I
understand that RLOG is not suited for this purpose. I will take a look at
the code snippets you've suggested and get back to you.

On Tue, Feb 16, 2010 at 8:30 AM, Pavan Balaji <balaji at mcs.anl.gov> wrote:

>
> On 02/15/2010 08:51 PM, sanath kumar wrote:
> > Oh I understand. I read through the logging.pdf file. RLOG is
> > independent of MPE right? My doubt is if RLOG can do the job of MPE,
> > what is the need for MPE? Can you point out some differences between the
> > both? Thank you.
>
> Yes, rlog and MPE are independent. rlog is for internal profiling of
> MPICH2 (inside the library), while MPE profiles at the MPI call level.
> So, both have their own specific purposes. The common aspect is that the
> logs generated by both these profilers can be converted to slog2 format
> which is viewable by Jumpshot.
>
> There are some differences in their implementations as well. For
> example, rlog does in-memory profiling. Which means that it can't
> profile very long running applications. There are some other differences
> in the details as well (such as rlog doesn't have any inter-process
> synchronization, so you get independent log files, which might not be
> time synchronized). You need to view these as two independent tools.
>
> If you are just looking to extend MPE to add additional profiling,
> instead of using rlog, you'll need to add more states (see the calls to
> MPID_MPI_STATE_DECL and MPID_MPI_FUNC_ENTER in MPIR_Bcast (bcast.c:981)
> for example). But my suggestion is still to just use rlog instead.
>
>  -- Pavan
>
> --
> Pavan Balaji
> http://www.mcs.anl.gov/~balaji
> _______________________________________________
> mpich-discuss mailing list
> mpich-discuss at mcs.anl.gov
> https://lists.mcs.anl.gov/mailman/listinfo/mpich-discuss
>



-- 
SANATH KUMAR
http://blog.ceglug.org/sanath
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/mpich-discuss/attachments/20100216/d654f4a5/attachment.htm>