# Controlling Number or Processes with SuperLU/MUMPS

**URL:** <https://fenicsproject.discourse.group/t/controlling-number-or-processes-with-superlu-mumps/9802>\
**Category:** Linear Algebra\
**Created:** [November 21, 2022, 1:57am UTC](https://fenicsproject.discourse.group/t/controlling-number-or-processes-with-superlu-mumps/9802 "2022-11-21T01:57:52Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![gideonsimpson](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/gideonsimpson/32/561_2.png) [@gideonsimpson](https://fenicsproject.discourse.group/u/gideonsimpson)\
**Post date:** [November 21, 2022, 1:57am UTC](https://fenicsproject.discourse.group/t/controlling-number-or-processes-with-superlu-mumps/9802/1 "2022-11-21T01:57:52Z")

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While I have no issue using `mpirun -np N` to control the number of processes when using a Krylov solver, I’m finding that if I try to use this with either `superlu_dist` or `mumps`, it just runs with all the cores on my system, no matter what I set for `N`. How do I control this?

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**Author:** ![dokken](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/dokken/32/1560_2.png) [@dokken](https://fenicsproject.discourse.group/u/dokken)\
**Post date:** [November 21, 2022, 6:47am UTC](https://fenicsproject.discourse.group/t/controlling-number-or-processes-with-superlu-mumps/9802/2 "2022-11-21T06:47:51Z")

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It might be worthwhile looking at [Multicore and Ubuntu - #7 by dparsons](https://fenicsproject.discourse.group/t/multicore-and-ubuntu/3080/7) and subsequent posts.