[Pw_forum] << running QE in parallel >>

[Lorenzo Paulatto]

Dear Camps,
let's have a look at all the output, not just the last line:


In data 28 agosto 2009 alle ore 16:42:01, I. Camps <i_camps at yahoo.com.br>  
ha scritto:
> ...
>      Parallel version (MPI)

This mean you have actually compiled the parallel version, good!

>      Number of processors in use:       1

But you are running it with only one processor.

>      Subspace diagonalization in iterative solution of the eigenvalue  
> problem:
>      Too few procs for parallel algorithm
>        we need at least 4 procs per pool
>      a serial algorithm will be used

Having only one processor, you also have less than 4 processors per pool,  
hence matrix diagonalization is done serially.

There must be an error in one of these lines, or in the way you combine  
them together. I cannot say which, because I don't use lam and I don't  
have access to the script you've used.

> export PARA_PREFIX="mpiexec -n 4"
> export PARA_POSTFIX="-npool 1"
> PWgui="/software/PWgui-4.1"

Double-check the script, maybe you only have to replace -n with -np.

best regards.


-- 
Lorenzo Paulatto
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