LanguageServer waiting for background task / IO / timer

[jj-du-plessis]

Whenever I run update to update my packages, I always get the following line

◐ LanguageServer Waiting for background task / IO / timer. Interrupt to inspect

which hangs for a while before yielding the following:

  1 dependency had output during precompilation:
┌ LanguageServer
│  [ Info: Package CSV (336ed68f-0bac-5ca0-87d4-7b16caf5d00b) is cached.
│  [ Info: Package BenchmarkTools (6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf) is cached.
│  [ Info: Package LanguageServer (2b0e0bc5-e4fd-59b4-8912-456d1b03d8d7) is cached.
│  [ Info: Package PyCall (438e738f-606a-5dbb-bf0a-cddfbfd45ab0) is cached.
│  [ Info: Package NPZ (15e1cf62-19b3-5cfa-8e77-841668bca605) is cached.
│  [ Info: Package JSON (682c06a0-de6a-54ab-a142-c8b1cf79cde6) is cached.
│  [ Info: Package StatsBase (2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91) is cached.
│  [ Info: Package SymPy (24249f21-da20-56a4-8eb1-6a02cf4ae2e6) is cached.
│  [ Info: Package Latexify (23fbe1c1-3f47-55db-b15f-69d7ec21a316) is cached.
│  [ Info: Package PyPlot (d330b81b-6aea-500a-939a-2ce795aea3ee) is cached.
│  [ Info: Package FileIO (5789e2e9-d7fb-5bc7-8068-2c6fae9b9549) is cached.
│  [ Info: Package FFTW (7a1cc6ca-52ef-59f5-83cd-3a7055c09341) is cached.
│  [ Info: Symbol server indexing took 8.704601967 seconds.
│  
│  [pid 478565] waiting for IO to finish:
│   Handle type        uv_handle_t->data
│   timer              0x152d1800->0x7fb9f301ef50
│  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 478565] waiting for IO to finish:
│   Handle type        uv_handle_t->data
│   timer              0x152d1800->0x7fb9f301ef50
│  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.
└  

I'm not sure what this means, and I'm not sure how to fix it. Please advise.

[AlexanderPerez23]

I have a similar issue, this completely broke the language server in my neovim setup and VSCode, none of the installed packages are recognized, and there is no autocomplete

(@v1.11) pkg> add LanguageServer.jl Resolving package versions... No Changes to /.julia/environments/v1.11/Project.tomlNo Changes to/.julia/environments/v1.11/Manifest.toml`
Precompiling project...
1 dependency successfully precompiled in 42 seconds. 261 already precompiled.
1 dependency had output during precompilation:
┌ LanguageServer
│ [ Info: Package Tullio (bc48ee85-29a4-5162-ae0b-a64e1601d4bc) is cached.
│ [ Info: Package ILUZero (88f59080-6952-5380-9ea5-54057fb9a43f) is cached.
│ [ Info: Package ForwardDiff (f6369f11-7733-5829-9624-2563aa707210) is cached.
│ [ Info: Package HiGHS (87dc4568-4c63-4d18-b0c0-bb2238e4078b) is cached.
│ [ Info: Package MPI (da04e1cc-30fd-572f-bb4f-1f8673147195) is cached.
│ [ Info: Package Test (8dfed614-e22c-5e08-85e1-65c5234f0b40) is cached.
│ [ Info: Package Random (9a3f8284-a2c9-5f02-9a11-845980a1fd5c) is cached.
│ [ Info: Package BenchmarkTools (6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf) is cached.
│ [ Info: Package Delaunator (466f8f70-d5e3-4806-ac0b-a54b75a91218) is cached.
│ [ Info: Package JuMP (4076af6c-e467-56ae-b986-b466b2749572) is cached.
│ [ Info: Package NearestNeighbors (b8a86587-4115-5ab1-83bc-aa920d37bbce) is cached.
│ [ Info: Package TimerOutputs (a759f4b9-e2f1-59dc-863e-4aeb61b1ea8f) is cached.
│ [ Info: Package FiniteDifferences (26cc04aa-876d-5657-8c51-4c34ba976000) is cached.
│ [ Info: Package Serialization (9e88b42a-f829-5b0c-bbe9-9e923198166b) is cached.
│ [ Info: Package AMD (14f7f29c-3bd6-536c-9a0b-7339e30b5a3e) is cached.
│ [ Info: Package IncompleteLU (40713840-3770-5561-ab4c-a76e7d0d7895) is cached.
│ [ Info: Package Lazy (50d2b5c4-7a5e-59d5-8109-a42b560f39c0) is cached.
│ [ Info: Package LinearAlgebra (37e2e46d-f89d-539d-b4ee-838fcccc9c8e) is cached.
│ [ Info: Package Ipopt (b6b21f68-93f8-5de0-b562-5493be1d77c9) is cached.
│ [ Info: Package Triangulate (f7e6ffb2-c36d-4f8f-a77e-16e897189344) is cached.
│ [ Info: Package NPZ (15e1cf62-19b3-5cfa-8e77-841668bca605) is cached.
│ [ Info: Package LoopVectorization (bdcacae8-1622-11e9-2a5c-532679323890) is cached.
│ [ Info: Package SparseArrays (2f01184e-e22b-5df5-ae63-d93ebab69eaf) is cached.
│ [ Info: Package WriteVTK (64499a7a-5c06-52f2-abe2-ccb03c286192) is cached.
│ [ Info: Package StaticArrays (90137ffa-7385-5640-81b9-e52037218182) is cached.
│ [ Info: Package JLD2 (033835bb-8acc-5ee8-8aae-3f567f8a3819) is cached.
│ [ Info: Package SpecialFunctions (276daf66-3868-5448-9aa4-cd146d93841b) is cached.
│ [ Info: Package UnPack (3a884ed6-31ef-47d7-9d2a-63182c4928ed) is cached.
│ [ Info: Package Setfield (efcf1570-3423-57d1-acb7-fd33fddbac46) is cached.
│ [ Info: Package Printf (de0858da-6303-5e67-8744-51eddeeeb8d7) is cached.
│ [ Info: Package Metis (2679e427-3c69-5b7f-982b-ece356f1e94b) is cached.
│ [ Info: Package Reexport (189a3867-3050-52da-a836-e630ba90ab69) is cached.
│ [ Info: Symbol server indexing took 2.728310792 seconds.
│
│ [pid 25608] waiting for IO to finish:
│ Handle type uv_handle_t->data
│ timer 0x60000a65b780->0x13a5270d0
│ 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 25608] waiting for IO to finish:
│ Handle type uv_handle_t->data
│ timer 0x60000a65b780->0x13a5270d0
│ 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.
└

(@v1.11) pkg>`

[wgmitchener]

I also see this in version 1.10.9. It looks like a lot of pipes have been opened, and the process connected to those pipes are still running, but I'm not sure what they are. I'm running Fedora Linux. I don't see anything useful in the list of running processes, like curl or wget.

[jorgenorena]

I have the same issue in version 1.11.5 on Ubuntu 25.04

[kewiechecki]

I have the same issue on Arch Linux with at least versions 1.11.5, 1.11.4, and 1.10.9.

[differentprogramming]

Same on both the release and beta on Windows.