# EXPLICIT and OMP\_NUM\_THREADS
**URL:** https://calculix.discourse.group/t/explicit-and-omp-num-threads/896
**Category:** Uncategorized
**Created:** [December 7, 2021, 11:45am UTC](https://calculix.discourse.group/t/explicit-and-omp-num-threads/896 "2021-12-07T11:45:35Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@toref](https://calculix.discourse.group/u/toref)
#### Post date: [December 7, 2021, 11:45am UTC](https://calculix.discourse.group/t/explicit-and-omp-num-threads/896/1 "2021-12-07T11:45:35Z")
Hi all, any help with the 2 below questions would be greatly appreciated - thanks in advance!
1. Can the \*DYNAMIC,DIRECT,EXPLICIT procedure utilize multiple cores?
**Background** : we experience no change in calculation time when increasing OMP\_NUM\_THREADS, ie from 6 to 12 – we have compiled with the \_MT option and can see in spooles.out that 12 threads where used. Furthermore for IMPLICIT calculations we _do_ see a speedup
2. Is the \*RIGID BODY card valid for \*DYNAMIC,DIRECT,EXPLICIT?
**Background:** When using \*RIGID we see a “local” deformation in the body as you would normally see in deforming bodies
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### Author:  [@Calc\_em](https://calculix.discourse.group/u/Calc_em)
#### Post date: [December 7, 2021, 2:42pm UTC](https://calculix.discourse.group/t/explicit-and-omp-num-threads/896/2 "2021-12-07T14:42:32Z")
Check this thread, part (but only part) of explicit solver algorithm is not done in parallel:
> [@Accessing the explicit solver](https://calculix.discourse.group/t/accessing-the-explicit-solver/385):
>
> Hello, I’m an experienced Abaqus user and have started having a play with Calculix. I want to try to run a wave propagation model using the explicit solver. I’ve used \*STEP, DYNAMIC, EXPLICIT and it runs but it’s very slow (about 25 times slower than it would have been with the Abaqus explicit solver). Is there any way to check if Calculix is actually using the explicit solver?
When it comes to rigid body, it should work in explicit dynamics procedure as well. Apparently, you came across some bug. This issue would require further research. Can you share more details about this?
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### Author:  [@feacluster](https://calculix.discourse.group/u/feacluster)
#### Post date: [December 7, 2021, 4:03pm UTC](https://calculix.discourse.group/t/explicit-and-omp-num-threads/896/3 "2021-12-07T16:03:12Z")
I am not familiar with \*DYNAMIC, but if you are concerned about performance, then I would not use spooles… Intel compiler is now free which has pardiso…