[gmx-users] mdrun -multi

[Anton Feenstra]

Nguyen Hoang Phuong wrote:

> Dear All,
> 
> I would like to run mdrun with the option -multi (multiple simulations in
> paralell). Suppose that I have 4 nodes (8cpus), is it possible to run 8
> simulations in parallel on these 8cpus?

AFAIK there is one, and only one!, sensible reason for using mdrun -multi
and that is when you have access to a supercomputer with rather strict
policies on the queues. That is, many supercomputer administrators require
that only parallel (and thus multi-processor) jobs can be run. If, in stead,
you have a (large) number of individual simulations that you want to run
you can use mdrun -multi to bypass this queuing policy by making the system
think you are running a paralell job, while you actually run multiple
independent simulations.

In all other cases, IMHO, you should simply start multiple separate instances
of mdrun!


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
|(   |   )| | | De Boelelaan 1083 - 1081 HV Amsterdam - Netherlands   |
| \_/ \_/ | | | Tel: +31 20 44 47608 - Fax: +31 20 44 47610           |
|             | Feenstra at chem.vu.nl - www.chem.vu.nl/~feenstra/       |
|             | "If You See Me Getting High, Knock Me Down"           |
|             | (Red Hot Chili Peppers)                               |
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