# Command: SetFakeNumProcesses

NEST HelpDesk | Command Index | NEST Quick Reference

Name:

    SetFakeNumProcesses - Set a fake number of MPI processes.

Synopsis:

    n_procs SetFakeNumProcesses ->	-

Description:

      Sets the number of MPI processes to n_procs. Used for benchmarking purposes
      of memory consumption only.
      Please note:
     	- Simulation of the network will not be possible after setting fake
      processes.
     	- It is not possible to use this function when running a script on multiple
      actual MPI processes.
     	- The setting of the fake number of processes has to happen before the kernel
      reset and before the setting of the local number of threads.
      After calling SetFakeNumProcesses, it is obligatory to call either
      ResetKernel or SetStatus on the Kernel for the setting of the fake
      number of processes to come into effect.

      A typical use case would be to test if a neuronal network fits on a machine
      of given size without using the actual resources.

      Example:
      %%% Set fake number of processes
      100 SetFakeNumProcesses
      ResetNetwork

      %%% Build network
      /iaf_psc_alpha 100 Create
      [1 100] Range /n Set

      << /source n /target n >> Connect

      %%% Measure memory consumption
      memory_thisjob ==

      Execute this script with
      mpirun -np 1 nest example.sli

Availability:

    NEST 2.2

Author:

    Susanne Kunkel

FirstVersion:

    July 2011

SeeAlso:

- NumProcesses

Source:

    /opt/conda/conda-bld/nest_1512418773968/work/nest-2.14.0/nestkernel/nestmodule.cpp

NEST HelpDesk | Command Index | NEST Quick Reference

© 2004 The NEST Initiative