# Parallel computation for openmc.deplete

**URL:** <https://openmc.discourse.group/t/parallel-computation-for-openmc-deplete/3752>\
**Category:** User Support\
**Created:** [December 16, 2023, 12:51pm UTC](https://openmc.discourse.group/t/parallel-computation-for-openmc-deplete/3752 "2023-12-16T12:51:11Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Tianxiang](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/tianxiang/32/3806_2.png) [@Tianxiang](https://openmc.discourse.group/u/Tianxiang)\
**Post date:** [December 16, 2023, 12:51pm UTC](https://openmc.discourse.group/t/parallel-computation-for-openmc-deplete/3752/1 "2023-12-16T12:51:11Z")

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Hi all:  
I’d like to run openmc.depletion on a multi-node computer to speed up calculations. I’m attempting to use 4 nodes with a total of 512 cores, but it seems that the computation speed isn’t significantly faster than running on a single node (only about 20% faster). I have limited knowledge of OPENMP and MPI. Can anyone help me identify if there’s an issue with my configuration?

> ![1702731039834](https://global.discourse-cdn.com/free1/uploads/openmc/original/2X/3/3bf8b682bf4f7f9171d73cdf9ca811fadea9b921.png)
> 
> ![ed8a43b681a376cc84ad5558c6d2162](https://global.discourse-cdn.com/free1/uploads/openmc/original/2X/7/77737e85b74a8aeeccaac86a4c0e7ab8dbd2d25c.png)

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**Author:** ![ASureda](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@ASureda](https://openmc.discourse.group/u/ASureda)\
**Post date:** [December 16, 2023, 4:07pm UTC](https://openmc.discourse.group/t/parallel-computation-for-openmc-deplete/3752/2 "2023-12-16T16:07:52Z")

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Hello, normally to take advantage of parallel computing performance you must ensure that the number of particles is high, i.e. there is a balance between computation time and communication time between nodes. I recommend you to have a look at some speedup concepts. In the past I did a project on parallel computing performance, in the link I give you you can see that as you increase the number of particles the performance increases with respect to serial computing. [MPI efficiency](https://github.com/Asureda/MPI-NVT/blob/main/Parallel%20efficiency/speedup%20BS.png).  
Therefore, try lowering the number of processors and look at the performance with respect to the serial computation by setting a number of particles. Or increase the number of particles a lot and compare with the serial computation.

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**Author:** ![Tianxiang](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/tianxiang/32/3806_2.png) [@Tianxiang](https://openmc.discourse.group/u/Tianxiang)\
**Post date:** [December 16, 2023, 4:46pm UTC](https://openmc.discourse.group/t/parallel-computation-for-openmc-deplete/3752/4 "2023-12-16T16:46:38Z")

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Thank you for your input! I’ll review your suggestions. Much appreciated!