# Why "Threads.@threads for " doesn't use all possible threads?
**URL:** https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711
**Category:** New to Julia
**Tags:** multithreading
**Created:** [January 23, 2020, 7:07pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711 "2020-01-23T19:07:40Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@BMval](https://discourse.julialang.org/u/BMval)
#### Post date: [January 23, 2020, 7:07pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/1 "2020-01-23T19:07:40Z")
Good day.
I have 12 cores. So nthread() gives 12.
when I used "Threads.@threads for ", only 8 thread was created.
RAM memory was utilized for up to 85%.
Can memory limitations and the number of thread created be connected?
thanks.
---
### Author:  [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)
#### Post date: [January 23, 2020, 8:41pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/2 "2020-01-23T20:41:00Z")
Please show what code you ran.
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### Author:  [@BMval](https://discourse.julialang.org/u/BMval)
#### Post date: [January 23, 2020, 8:45pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/3 "2020-01-23T20:45:02Z")
```julia
function main()
files=readdir()
Threads.@threads for file in files
if file[end-1:end]=="gz"
println("threadid-",threadid(), " ", file)
df=ParseFile(file)
println("threadid-",threadid(), " ","Parsefile")
df=KeepUniqueId(df)
println("threadid-",threadid(), " ","KeepUnique")
dfNews=ParseSubjects(df)
println("threadid-",threadid(), " ","ParseSubjests")
filename=file[1:end-7]
CSV.write("$file.csv",dfNews)
end
end
end
```
The DataFrame size is around 1Gb.
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### Author:  [@jlapeyre](https://discourse.julialang.org/u/jlapeyre)
#### Post date: [January 23, 2020, 8:52pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/4 "2020-01-23T20:52:34Z")
See the first item here: [Please read: make it easier to help you](https://discourse.julialang.org/t/psa-make-it-easier-to-help-you/14757)
---
### Author:  [@Sukera](https://discourse.julialang.org/u/Sukera)
#### Post date: [January 23, 2020, 9:08pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/5 "2020-01-23T21:08:35Z")
> [@BMval](#):
>
> files=readdir() Threads.@threads for file in files
How many files are in that directory?
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### Author:  [@BMval](https://discourse.julialang.org/u/BMval)
#### Post date: [January 23, 2020, 9:09pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/6 "2020-01-23T21:09:52Z")
Around 10-12. it’s more than a number of threads.
---
### Author:  [@BMval](https://discourse.julialang.org/u/BMval)
#### Post date: [January 23, 2020, 9:38pm UTC](https://discourse.julialang.org/t/why-threads-threads-for-doesnt-use-all-possible-threads/33711/7 "2020-01-23T21:38:26Z")
Maybe I got the answer
“Threads.@threads for” tries distribute evenly a number of threads since when I have exactly 12 files, 12 threads were created.