[ESPResSo] Re: Re: Parallel Simulations and System Initialization

[Lorenzo Isella]

Hello,
And thanks for the suggestions.
As to the infiniband-adaptor, I am really in a bad shape (had to google 
it up and not sure I understand what that stands for).
For now, I have re-compiled Espresso with the --without-mpi option. 
However, does this infiniband thing mean that even if I managed to set 
up properly the  environment for the parallel libraries, they would not 
work on my machine in the present situation?
And a final question (definitely not entirely related to Espresso): my 
first target would be to make use of the 2 dual-core processors 
(actually, 4 CPU's) available on my desktop machine.
Any specific recommendation for a tutorial for an absolute beginner in 
this field to use e.g. OpenMPI on a single multi-core machine rather 
than a cluster?
Cheers

Lorenzo

> There are two packages that Espresso is known to work with: LAM/MPI and MPICH. 
> However, this will not solve your problems: LAM also requires you to prepare 
> your computer for parallel runs; this has nothing to do with Espresso itself, 
> but is a requirement of the parallel library. In case of LAM, for example, 
> you need to execute lamboot before running your application, and lamhalt 
> after running it. I think MPICH has a mode that does not require an external 
> daemon, but is typical less performant than LAM.
>
> The error that you obtain from LAM regarding "OpenIB" indicates that somehow 
> your OpenMPI installation tries to use an non-existing infiniband-adaptor. 
> Maybe you first want to check why OpenMPI wants to use Infiniband...
>