# Precompiling causing system freeze

**URL:** <https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008>\
**Category:** New to Julia\
**Created:** [May 28, 2021, 5:46pm UTC](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008 "2021-05-28T17:46:07Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![evad](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/evad/32/15756_2.png) [@evad](https://discourse.julialang.org/u/evad)\
**Post date:** [May 28, 2021, 5:46pm UTC](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008/1 "2021-05-28T17:46:07Z")

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Hi,  
I’m on a 10y-old machine, and each time I updated a few packages, a whopping 100+ packages got recompiled, and system hung if other resource intensive apps like YouTube page were running. I noticed compiling in R/Haskell etc use less system resource ( by the fact YouTube still plays and system doesn’t freeze). So can I know why this is happening and whether it possible to lower Julia’s precompiling load on memory?

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**Author:** ![fredrikekre](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/fredrikekre/32/1688_2.png) [@fredrikekre](https://discourse.julialang.org/u/fredrikekre)\
**Post date:** [May 28, 2021, 6:28pm UTC](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008/2 "2021-05-28T18:28:12Z")

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You can disable automatic precompilation by setting the environment variable `JULIA_PKG_PRECOMPILE_AUTO` to `0`, or you can limit the number of concurrent precompilation tasks by setting `JULIA_NUM_PRECOMPILE_TASKS`. See [docstring for `Pkg.precompile`](https://github.com/JuliaLang/Pkg.jl/blob/2029bee7e94140aa0614f7ec4077042c419a2fe9/src/Pkg.jl#L147-L148).

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**Author:** ![pixel27](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/pixel27/32/8902_2.png) [@pixel27](https://discourse.julialang.org/u/pixel27)\
**Post date:** [May 28, 2021, 6:39pm UTC](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008/3 "2021-05-28T18:39:02Z")

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If you are on Linux I wonder if `nice julia` would work for you by lowering Julia’s priority so your important applications can run. 🙂

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**Author:** ![evad](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/evad/32/15756_2.png) [@evad](https://discourse.julialang.org/u/evad)\
**Post date:** [May 29, 2021, 6:04am UTC](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008/5 "2021-05-29T06:04:27Z")

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I don’t know nice is a shipped command…let me try