> Is it possible to configure/run OpenMPI in a such way, that only _one_
> process (e.g. master) performs real disk I/O, and other processes sends the
> data to the master which works as an agent?
It is possible to run OpenMPI this way, but it is not a matter of configuration,
but of implementation alone.
> Of course this would impacts the performance, because all data must be send
> over network, and the master may became a bottleneck. But is such scenario -
> IO of all processes bundled to one process - practicable at all?
I think this question can only be answered by trying, because it
on the volume of your messages and the quality of your hardware
(network and disk speed)