# Only 1 BLAS thread in 1.9-beta2

**URL:** <https://discourse.julialang.org/t/only-1-blas-thread-in-1-9-beta2/92578>\
**Category:** Performance\
**Created:** [January 5, 2023, 10:28pm UTC](https://discourse.julialang.org/t/only-1-blas-thread-in-1-9-beta2/92578 "2023-01-05T22:28:22Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![PeterSimon](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/petersimon/32/25193_2.png) [@PeterSimon](https://discourse.julialang.org/u/PeterSimon)\
**Post date:** [January 5, 2023, 10:28pm UTC](https://discourse.julialang.org/t/only-1-blas-thread-in-1-9-beta2/92578/1 "2023-01-05T22:28:22Z")

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When I start up Julia 1.9-beta2 on my 8-core Windows machine, `BLAS.get_num_threads()` returns `1` (whether or not I start with the `-t8` option. Is this intended behavior or a bug?

```julia
PS D:\peter\Documents> julia
               _
   _ _ _(_)_ | Documentation: https://docs.julialang.org
  (_) | (_) (_) |
   _ _ _| |_ __ _ | Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` | |
  | | |_| | | | (_| | | Version 1.9.0-beta2 (2022-12-29)
 _/ |\ __'_|_|_|\__'_| | Official https://julialang.org/ release
|__/ |

julia> using LinearAlgebra

julia> BLAS.get_num_threads()
1

julia> versioninfo()
Julia Version 1.9.0-beta2
Commit 7daffeecb8 (2022-12-29 07:45 UTC)
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: 8 × Intel(R) Core(TM) i7-9700 CPU @ 3.00GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-14.0.6 (ORCJIT, skylake)
  Threads: 1 on 8 virtual cores
Environment:
  JULIA_EDITOR = runemacs.exe

```

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<div class="post-metadata">

**Author:** ![Hawkes](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/hawkes/32/22365_2.png) [@Hawkes](https://discourse.julialang.org/u/Hawkes)\
**Post date:** [January 5, 2023, 10:30pm UTC](https://discourse.julialang.org/t/only-1-blas-thread-in-1-9-beta2/92578/2 "2023-01-05T22:30:52Z")

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This will be fixed in 1.9-beta3: [Bad default number of BLAS threads on 1.9? · Issue #48062 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/issues/48062)

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<div class="post-metadata">

**Author:** ![ctkelley](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ctkelley/32/10684_2.png) [@ctkelley](https://discourse.julialang.org/u/ctkelley)\
**Post date:** [January 6, 2023, 12:18am UTC](https://discourse.julialang.org/t/only-1-blas-thread-in-1-9-beta2/92578/3 "2023-01-06T00:18:14Z")

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While you wait, put this in your `startup.jl` file.

```julia
BLAS.set_num_threads(8)

```