# How to use all thread during mdrun

**URL:** <https://gromacs.bioexcel.eu/t/how-to-use-all-thread-during-mdrun/9481>\
**Category:** User discussions\
**Created:** [June 23, 2024, 12:50pm UTC](https://gromacs.bioexcel.eu/t/how-to-use-all-thread-during-mdrun/9481 "2024-06-23T12:50:20Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![amir](https://avatars.discourse-cdn.com/v4/letter/a/c37758/32.png) [@amir](https://gromacs.bioexcel.eu/u/amir)\
**Post date:** [June 23, 2024, 12:50pm UTC](https://gromacs.bioexcel.eu/t/how-to-use-all-thread-during-mdrun/9481/1 "2024-06-23T12:50:20Z")

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GROMACS version: 2024.2

I have a computer with 16 cores and 32 threads. But, during mdrun 16 theards were used. how can i force gromacs to use 32 theards at once?  
also i set -ntomp 32 but nothing changed.  
I’d really appreciate it if someone help me.

 ![Screenshot from 2024-06-23 16-32-08](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/2X/1/176bfd4206dd6a275626e134c635bc98f493e61c.png)  
as you can see below, 16 threads were used:  
 ![Screenshot from 2024-06-23 16-24-32](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/2X/8/8935776b0b6729809891f4efca8c942805b2ae92.png)

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**Author:** ![obZehn](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/obzehn/32/2629_2.png) [@obZehn](https://gromacs.bioexcel.eu/u/obZehn)\
**Post date:** [June 23, 2024, 3:35pm UTC](https://gromacs.bioexcel.eu/t/how-to-use-all-thread-during-mdrun/9481/2 "2024-06-23T15:35:13Z")

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You have 16 physical cores, they are reported as 32 because of [hyperthreading](https://en.wikipedia.org/wiki/Hyper-threading). I think there is basically no advantage in using hyperthreading with GROMACS, so `-ntomp` is usually equal to the number of physical cores you want to use, which in your case is 16 if you want to use them all!