Downloads trailing task warning during precompilation on 1.11rc2 and 1.11rc3

[ufechner7]

julia> versioninfo()
Julia Version 1.11.0-rc2
Commit 34c3a63147b (2024-07-29 06:24 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 16 × AMD Ryzen 7 7840U w/ Radeon  780M Graphics
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, znver4)
Threads: 1 default, 0 interactive, 1 GC (on 16 virtual cores)

Test script:

#!/bin/bash -eu
rm -rf /tmp/testdepot
mkdir /tmp/testdepot
rm -rf /tmp/test
mkdir /tmp/test
cd /tmp/test
export JULIA_DEPOT_PATH=/tmp/testdepot 
julia --project="." -e "using Pkg; Pkg.add(\"LinearSolve\"); using LinearSolve"
cd ..

Output:

       Info Packages marked with ⌅ have new versions available but compatibility constraints restrict them from upgrading. To see why use `status --outdated -m`
Precompiling project...
  104 dependencies successfully precompiled in 67 seconds. 21 already precompiled.
  1 dependency had output during precompilation:
┌ MKL_jll
│   Downloading artifact: MKL
│  
│  [pid 29931] waiting for IO to finish:
│   Handle type        uv_handle_t->data
│   timer              0x591eb7b98610->0x7029f5fa8670
│  This means that a package has started a background task or event source that has not finished running. For precompilation to complete successfully, the event source needs to be closed explicitly. See the developer documentation on fixing precompilation hangs for more help.
│  
│  [pid 29931] waiting for IO to finish:
│   Handle type        uv_handle_t->data
│   timer              0x591eb7b98610->0x7029f5fa8670
│  This means that a package has started a background task or event source that has not finished running. For precompilation to complete successfully, the event source needs to be closed explicitly. See the developer documentation on fixing precompilation hangs for more help.

This issue does also appear with Julia 1.10.4, but is fixed in the release-1.10 branch.
It is a Pkg issue.

[ufechner7]

See also: #3950

The comment "is alrady fixed in 1.11" is wrong.

[jishnub]

This should probably be moved to the Pkg.jl repo?

[ufechner7]

This should probably be moved to the Pkg.jl repo?

Who could do that? I would not know how to do that.

[jishnub]

Some admin of the org. Either way, I'll not worry about it, as it'll reach the right eyes. The Pkg repo has less activity, so the issue is less likely to be lost.

[giordano]

Some admin of the org.

You can also do it by clicking on the "transfer issue" button on the right sidebar

[ufechner7]

Same problem on Julia 1.11rc3. Can this be added to the 1.11 milestone?

[giordano]

Why? It has been there forever, why it should suddenly become a release blocker?

[IanButterworth]

Can someone with an intel cpu check whether this reproduces on nightly julia?

% JULIA_DEPOT_PATH=$(mktemp -d): julia +1.11 --start=no -e 'using Pkg; Pkg.add("LinearSolve"); using LinearSolve'

[jishnub]

Output on nightly v"1.12.0-DEV.1106" using

JULIA_DEPOT_PATH=$(mktemp -d): julia +nightly --startup=no -e 'using Pkg; Pkg.add("LinearSolve"); using LinearSolve'

[...]
Precompiling all packages...
  95 dependencies successfully precompiled in 108 seconds. 33 already precompiled.
  1 dependency had output during precompilation:
┌ MKL_jll
│   Downloading artifact: MKL
│  
│  [pid 46097] waiting for IO to finish:
│   Handle type        uv_handle_t->data
│   timer              0x196ea00->0x752a7a1aad10
│  This means that a package has started a background task or event source that has not finished running. For precompilation to complete successfully, the event source needs to be closed explicitly. See the developer documentation on fixing precompilation hangs for more help.
│  
│  [pid 46097] waiting for IO to finish:
│   Handle type        uv_handle_t->data
│   timer              0x196ea00->0x752a7a1aad10
│  This means that a package has started a background task or event source that has not finished running. For precompilation to complete successfully, the event source needs to be closed explicitly. See the developer documentation on fixing precompilation hangs for more help.
└  

versioninfo:

julia> versioninfo()
Julia Version 1.10.4
Commit 48d4fd48430 (2024-06-04 10:41 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 12 × Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, skylake)
Threads: 1 default, 0 interactive, 1 GC (on 12 virtual cores)
Environment:
  JULIA_EDITOR = subl

[ufechner7]

Why? It has been there forever, why it should suddenly become a release blocker?

Because it is fixed in Julia 1.10.5

[IanButterworth]

@jishnub seems you're on 1.10.4?

julia> versioninfo()
Julia Version 1.10.4

[jishnub]

That's just for the versioninfo which I generated separately, mainly for the CPU info

[IanButterworth]

Ok, please update it for clarity. The commit info is helpful.

[IanButterworth]

For anyone trying to repro this, this works for all architectures, not just intel.

% JULIA_DEPOT_PATH=$(mktemp -d): julia +1.11 --start=no -e 'using Pkg; Pkg.add("MicroMamba");'

I'm looking into what's happening here.

[IanButterworth]

Found the issue. The Downloads atexit tidy up function was only being registered when precompiling Downloads itself, which meant the test case in Downloads was fixed but not in any packages that use Downloads. JuliaLang/Downloads.jl#257