# Flux parallel execution
**URL:** https://discourse.julialang.org/t/flux-parallel-execution/12931
**Category:** Machine Learning
**Tags:** flux
**Created:** [August 6, 2018, 9:27am UTC](https://discourse.julialang.org/t/flux-parallel-execution/12931 "2018-08-06T09:27:10Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@kkmann](https://discourse.julialang.org/u/kkmann)
#### Post date: [August 6, 2018, 9:27am UTC](https://discourse.julialang.org/t/flux-parallel-execution/12931/1 "2018-08-06T09:27:11Z")
Hi,
so, this might be a very dumb question but how do I train model in flux.jl in parallel on my cpu?
---
### Author:  [@groot](https://discourse.julialang.org/u/groot)
#### Post date: [December 10, 2018, 12:59am UTC](https://discourse.julialang.org/t/flux-parallel-execution/12931/2 "2018-12-10T00:59:14Z")
Same question. MNIST demo in model zoo runs on a single core only. I am even surprised that Flux doesn’t run on multiple cores by default. Isn’t it mainly matrix multiplication which is paralleled by Julia?
Edit:
It does supported by julia. set JULIA\_NUM\_THREADS env variable will do the trick
I use following before running julia
```julia
export JULIA_NUM_THREADS=6
```
---
### Author:  [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)
#### Post date: [December 10, 2018, 5:33am UTC](https://discourse.julialang.org/t/flux-parallel-execution/12931/3 "2018-12-10T05:33:04Z")
I have implemented a manual model-parallel computations, where each model is evaluated on a single thread and on the end their gradient is averaged. It is faster in some cases. But I believe that the overall goal should be to have underlying routines multi-threaded.
The implementation is here.
>
---
### Author:  [@stegua](https://discourse.julialang.org/u/stegua)
#### Post date: [March 29, 2019, 3:48pm UTC](https://discourse.julialang.org/t/flux-parallel-execution/12931/4 "2019-03-29T15:48:33Z")
In Windows you have to set the enviroment variable using the Control Panel.