# macOS M1, Julia 1.6, and swtch\_pri

**URL:** https://discourse.julialang.org/t/macos-m1-julia-1-6-and-swtch-pri/59826
**Category:** Performance
**Tags:** mac-m1
**Created:** [April 22, 2021, 8:05pm UTC](https://discourse.julialang.org/t/macos-m1-julia-1-6-and-swtch-pri/59826 "2021-04-22T20:05:45Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![GlenHenshaw](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/glenhenshaw/32/5269_2.png) [@GlenHenshaw](https://discourse.julialang.org/u/GlenHenshaw)
#### Post date: [April 22, 2021, 8:05pm UTC](https://discourse.julialang.org/t/macos-m1-julia-1-6-and-swtch-pri/59826/1 "2021-04-22T20:05:45Z")

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Hi all,

Using a MacBook Air M1 and Julia 1.6.

I’m running a fairly complex scientific code that does a ton of matrix vector calculations. When I profile it and display the results using PProf, it shows that approximately 80% of the time is spent in the Mach system call swtch\_pri. This does not show up when I do a Profile.print().

I’m confused. I’m not doing any explicit threading, although I am doing a lot of vectorized operations. Any idea if this is fixable, and if so how?

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### Author: ![wsshin](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/wsshin/32/360_2.png) [@wsshin](https://discourse.julialang.org/u/wsshin)
#### Post date: [January 18, 2022, 1:38am UTC](https://discourse.julialang.org/t/macos-m1-julia-1-6-and-swtch-pri/59826/2 "2022-01-18T01:38:29Z")

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Not sure if related, but Julia started providing the native M1 support from version 1.7: [Julia 1.7 Highlights](https://julialang.org/blog/2021/11/julia-1.7-highlights/#support_for_apple_silicon).