[Pw_forum] How to choose number of pools

[Lorenzo Paulatto]

In data 30 aprile 2009 alle ore 16:18:38, Ihsan Erikat <ihsanas at yahoo.com>  
ha scritto:

> Hello all
> I am  running pwscf on 10 CPU

how are they connected to each other?

> and  the k points in my file is 3x6x1.

how many kpoints do you have after symmetry operations have been applied?

> When I use  the command mpirun -np xx  pw.x -npool x , how can I choose   
> the effective number of processors and pools.

All processors inside the same pool must be able to comunicate with each  
other with an extremely large bandwidth and low latency. You can have a  
benefit by taking the number of pools as a divisor of the number of  
kpoints, especially if the number of kpoints is small.

regards


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Lorenzo Paulatto
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