# Julia faster on Mac OSX than in linux?

**URL:** https://discourse.julialang.org/t/julia-faster-on-mac-osx-than-in-linux/9839
**Category:** New to Julia
**Created:** [March 20, 2018, 4:00pm UTC](https://discourse.julialang.org/t/julia-faster-on-mac-osx-than-in-linux/9839 "2018-03-20T16:00:12Z")
**Posts on this page:** 1
**Showing post:** 15

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### Author: ![Ralph\_Smith](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ralph_smith/32/10344_2.png) [@Ralph\_Smith](https://discourse.julialang.org/u/Ralph_Smith)
#### Post date: [March 21, 2018, 2:18am UTC](https://discourse.julialang.org/t/julia-faster-on-mac-osx-than-in-linux/9839/15 "2018-03-21T02:18:17Z")

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(back on topic)

> [@v-i-s-h](#):
>
> CPU: Intel(R) Core™ i7-7700 CPU @ 3.60GHz  
> WORD\_SIZE: 64  
> BLAS: libopenblas (USE64BITINT DYNAMIC\_ARCH NO\_AFFINITY Prescott)

This probably means that OpenBLAS does not correctly identify your new processor, so it is not using the best SIMD instructions. (Prescott is the fallback architecture.)

You could build Julia to use MKL for BLAS, or you can try to force OpenBLAS to use the Haswell target. (See the README at [the main Julia repo](https://github.com/JuliaLang/julia) for instructions.)

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