On Sun, 1 Jun 2003, John Darrington wrote:
> I'm trying to get started with XMPI to help me profile my code.
>
> Can someone tell me :
>
> a) What do the different colours red/yellow/green actually mean ?
Green is time spent in user code - outside of an MPI call. Yellow is time
spent in an MPI call, but not actively sending messages. And red is time
spent transporting the data around.
> b) Why don't I see the white lines between the ranks as the web page
> at http://www.lam-mpi.org/software/xmpi/ shows?
White lines are point to point communication. At present, only the MPI-1
pt-2-pt functions draw white lines. Also, a line (or partial line for an
unmatched send/recv) is only drawn once the send/recv finishes.
> c) On the timeline, what units are the numbers? Presumably they're
> seconds. But is this cpu time, elapsed time or what?
The units are wall-clock seconds, found by calling gettimeofday(). There
is a reasonable clock adjustment algorithm to try to keep all the
temporal problems under control, but it is by no means always right. So
things sometimes look weird on nodes 1 -> N, as XMPI tried to adjust for
clock drift versus that of node 0.
> d) When I click on Help->Help it tries to launch netscape and load the
> page: http://www.mpi.nd.edu/lam/software/xmpi/xmpi-help.php3
>
> This causes two problems:
>
> 1. I don't have netscape. How can I configure it to launch
> mozilla instead?
>
> 2. That web page doesn't exist anyway. Where has it moved to?
Hehe. I'll have to look at that. Back when that was written, Netscape
was the only browser for Unix. The new URL is:
http://www.lam-mpi.org/software/xmpi/help.php
> By the way: XMPI Version: XMPI 2.23b6 / LAM-libxmpi 6.5.3
>
>
> Thanks
>
>
>
--
Brian Barrett
LAM/MPI developer and all around nice guy
Have a LAM/MPI day: http://www.lam-mpi.org/
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