[mvapich-discuss] mvapich2 + PGI + TCP/IPoIB

[Olafur Rognvaldsson]

Howdy all.

> It doesn't appear that /usr/pgi/linux86-64/6.1/license.dat exists, so
> double-check to make sure you have set the LM_LICENSE_FILE environment
> variable correctly. You may need to set this value to a FLEXlm license
> server, depending on your setup.

Well, if this does not make me look like a total ass I don't know what will:-) 
The LM_LICENSE_FILE env variable was set in my .bashrc file, but as I was 
doing this as root everything went bananas.

> Please let us know if you have any other questions or if this does not
> solve your problem.

MVAPICH2 installes and runs smoothly. However, the results for running the MM5 
weather model on 20 CPU's are discouraging. On average I'm only getting about 
35% CPU usage and the model is veeery slow.

My "educated" guess is that MVAPICH2 is not taking advantage of the Topspin 
IPoIB software. Any thoughts on this???

Using Topspin MPI, I'm getting approximately 89% and 83% scaling with 12 and 
20 CPUs, respectively (as compared to running MM5 on a single CPU).

All the best, Ólafur.
-- 
Ólafur Rögnvaldsson 
or at os.is
http://www.os.is/~or/rev
Phone: +(354) 569 6000
           +(354) 864 4943