[Pw_forum] serial run when parallel intended

[Stefano de Gironcoli]

because the code estimate that the communication overhead would exceed 
the gain due to the distribution of the operation across the processors.
This apply to the subspace diagonalization, the rest of the run is parallel

stefano

On 04/11/2011 08:52 AM, Omololu Akin-Ojo wrote:
> Hi,
>
> I was aiming to run QE in parallel but I see the following message in
> my output file; what am i doing wrong?
>
>       Subspace diagonalization in iterative solution of the eigenvalue problem:
>       a serial algorithm will be used
>
> Why is QE using a serial algorithm? I am using openmpi and QE
> recognizes the number of processors correctly:
>       Parallel version (MPI), running on     8 processors
>       R&  G space division:  proc/pool =    8
>
> I could give more info if needed.
>
> Thanks in advance for any help.
>
> o.
>
> Postdoctoral fellow,
> CMSP section,
> ICTP, Italy.
>
>
>