[GAP Forum] A question about ParGAP

[Sara Yaftian]

Dear Alexander

Thank you very much for your helpful message. I have a question about your
last message.
How to use master-salve communication?
On the other hand, I need to use 5 CPU's, but MPI in ParGAP used 2 CPU's.
Is there any command to solve this problem?

Best regards
Sara

On Wed, Jan 6, 2016 at 1:00 AM, Alexander Konovalov <alexk at mcs.st-and.ac.uk>
wrote:

> Dear Sara,
>
> > On 5 Jan 2016, at 10:50, Sara Yaftian <sara.yaftian at gmail.com> wrote:
> >
> > Dear Forum
> >
> > I have a question about ParGAP.
> > I installed parGAP by the following command
> >
> > cd pargap
> > ./configure
> > make
> >
> > and then I need mpi and I installed mpi.
> > Finally I paralleled a GAP program on Linux (Ubuntu 14.04 LTS) by the
> > following command:
> >
> > mpiexe -np 5 ./pargap.sh
>
> Thank you for your question, and Happy New Year to you too! The above
> steps seem to be correct. The rest depends on what "myprogram.txt" is
> doing - it is quite common that when one tries to parallelise the code
> then the first version of the parallel code runs slower than the
> sequential one.
>
> Also, the phrase "I paralleled a GAP program" sounds a bit ambiguous, so
> just in case: what
>
> mpiexe -np 5 ./pargap.sh
>
> command is doing is that it starts several copies of GAP. One of them is
> called 'master', and it provides the GAP command line interface and
> communicates with all the others, called 'slaves'. If you will call
>
> Read("myprogram.txt");
>
> but the code there does not use any master-slave communication, it will
> just perform the calculation on the master.
>
> Best wishes
> Alexander
>
>
>
>
>
>
>
>
> >
> > when GAP run then I typed Read("myprogram.txt");
> >
> > I am not sure my commands are correct or not because my laptop use 5 of
> CPU
> > but the speed of my program has not changed. Would you please help me?
> >
> > I wish you have a very happy New Year 2016.
> >
> > Best regards
> > Sara
>
>
>