# Julia processes on a NUMA dual processor machine

**URL:** https://discourse.julialang.org/t/julia-processes-on-a-numa-dual-processor-machine/2943
**Category:** General Usage
**Tags:** question
**Created:** [March 29, 2017, 12:23am UTC](https://discourse.julialang.org/t/julia-processes-on-a-numa-dual-processor-machine/2943 "2017-03-29T00:23:02Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![rcnlee](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rcnlee/32/4107_2.png) [@rcnlee](https://discourse.julialang.org/u/rcnlee)
#### Post date: [March 29, 2017, 12:23am UTC](https://discourse.julialang.org/t/julia-processes-on-a-numa-dual-processor-machine/2943/1 "2017-03-29T00:23:02Z")

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Hello,

I have a program that spawns a number of julia processes and runs some code on them. The code uses `@async` in a way that is similar to the sample pmap code in the julia documentation. The problem that I am seeing is that half the processes complete in the expected amount of time, but the other half take more than 5x the time. I am on a server machine with dual processors (each processor has 8 cores), NUMA enabled, hyperthreading disabled, and running Windows 10 (Hyper V host, no VMs running).

Are there any gotchas to using Julia and spawning Julia processes in a dual processor NUMA setting?

Thanks,

Ritchie

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### Author: ![miguelraz](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/miguelraz/32/631_2.png) [@miguelraz](https://discourse.julialang.org/u/miguelraz)
#### Post date: [March 29, 2017, 3:23am UTC](https://discourse.julialang.org/t/julia-processes-on-a-numa-dual-processor-machine/2943/2 "2017-03-29T03:23:48Z")

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Ritchie! Welcome! Perhaps it’s best that you provide some actual code - a Minimum Working Example would help others help you.  
Otherwise, it’s hard to know general gotchas.  
Can you provide your Julia Version as well?  
Also, consider using `BenchmarkTools.jl` for useful stats.

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### Author: ![rcnlee](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rcnlee/32/4107_2.png) [@rcnlee](https://discourse.julialang.org/u/rcnlee)
#### Post date: [March 30, 2017, 9:42pm UTC](https://discourse.julialang.org/t/julia-processes-on-a-numa-dual-processor-machine/2943/3 "2017-03-30T21:42:19Z")

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Thanks Miguel,

Turns out this is not Julia-related at all. It’s a hardware issue!

Ritchie