[gmx-users] PARALLEL PROBLEM

[Osmany Guirola Cruz]

Hi 
 I have a problem with gromacs and my linux cluster  look at this.

system with ~4000atoms(200ps)           system with ~40000atoms(40ps)
1 machine  1 micro   12589s                 1 machine  1 micro   8312s
1 machine  2 micro     7410s                 1 machine  2 micro   5060s
2 machine  4 micro     7535s                 2 machine  4 micro   5765s
4 machine  8 micro     6272s                 4 machine  8 micro   3701s
8 machine 16 micro    8783s                 8 machine 16 micro  3629s 
i am using coulomtype=cuttoff if i  use PME its worst

and this is not very funny, I did a test with NAMD and it works 
perfectly(scalable) but i hate NAMD, it's a real pain. which is the 
diference? I think that my problem is the MPI library . now i am using the 
rpm of my distribution (SuSE 8.1).(I think that i have to compile it). If 
this is the solution ,i need to know which are the options for do it. In the 
site of gromacs there are a rpm , is this the correct to resolve this 
problem? ,PLEASE tell me what to do
I have a lot of work and run a simulaton in 1 machine with the posibility to 
use 32 it is terrible
 HELP ME 
            thanks