[Pw_forum] speedup of md simulation

[Paolo Giannozzi]

Hi

> [...] As to the planewave parallelization, I have tried other ab intio
> software package like CPMD. It seems the speedup there is much greater
> (around a factor of 5 on my 10 dual processor cluster). does the different
> performance stem from different methodologies that are utilized in those
> simulation packages?

No, I don't think so.

Remember that
- there is an optimal number of processors for each problem
- for small calculations, you may not gain anything from parallelization
- if you have dual processors, you may choose whether running
  two processes per node with MPI parallelization, or one process
  per node with automatic parallelization provided by libraries.
  Verify that you are not doing both, or they will conflict.

Paolo

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Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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