[Zaphod-Users] zaphod update

[Kai Germaschewski]

With the a/c in the machine room working at reduced capacity, zaphod is
now partially available again.

In course of the maintaince on Mon and continued downtime, we also made 
significant changes to zaphod's software. In particular, we had to upgrade 
kernel and gm (the Myrinet driver) in preparation to support 32-bit MPI 
applications. A consequence of this is that all applications will need 
recompiling with current mpich / gm drivers.

We also installed a software management tool called "modules", probably 
familiar to other supercomputers' users.

A short introduction is available e.g. on 
http://www.nersc.gov/nusers/resources/software/os/modules.php

In particular, if you would like to use the PGI compilers, the command

$ module load pgi

will do the necessary preparations. If you would like to use mpich,

$ module load mpich/gm

or 

$ module load mpich/p4

will set the environment for use of mpich (Myrinet version and ethernet 
version, respectively).

There are most likely bugs in the current configuration, and some things 
might break in the course of the ongoing work, but we're trying to keep 
things running and usable.

If you experience any kind of issues, please let us know, since we won't 
fix problems we don't know about ;)

--Kai