[mpich-discuss] Hydra framework (thru Grid Engine)

[Pavan Balaji]

Hi Bernard,

On 12/12/2011 08:58 AM, Bernard Chambon wrote:
> 1/ After compiling hydra framework, I didn't find mpicc in hydra directories
> (so I used mpicc in older mpich2 install)
> Do I need to understand that hydra is "only" an execution framework
> (mpiexec, etc.) ?

Correct.  Hydra just provides the execution framework.  You can compile 
your application with any version of MPICH2 or its derivatives, but it 
is recommended that you use the latest version.

> 2/ with Hydra (1.4.1p1) , is it possible to use 10 GigE TCP interface
> We have machines with two TCP interfaces (eth0 = 1Gb/s, eth2 = 10Gb/s)
> with Hydra I can't use eth2 even when specifying -iface eth2

This should work correctly.  Just to make sure you are using this right: 
setting the -iface option makes sure that your application is using the 
eth2 interface, so MPI communication will use eth2.  Hydra itself will 
use the default network interface for launching processes, unless it 
finds a local interface in your host file list.  If the SGE provided 
host list is using the 1GE interface, it will use 1GE.

You might or might not care about what network interface is used for 
launching processes, but I want to make sure you are checking the 
network usage on the right machines.

> To be more explicit, running :
> mpiexec -rmk sge -iface eth2 -n $NSLOTS ./bin/advance_test

The "-rmk sge" and "-n $NSLOTS" parts should be autodetected, so you 
don't need to provide them.

> Other reason for using hydra, is that mpd process are not very stable
> (in my configuration)

Please don't use MPD.  It's not supported anymore.

  -- Pavan

-- 
Pavan Balaji
http://www.mcs.anl.gov/~balaji