# What does manifest\_usage.toml file do?
**URL:** https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633
**Category:** General Usage
**Tags:** question, manifest
**Created:** [October 31, 2023, 10:29pm UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633 "2023-10-31T22:29:35Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@math\_opt](https://discourse.julialang.org/u/math_opt)
#### Post date: [October 31, 2023, 10:29pm UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/1 "2023-10-31T22:29:35Z")
As the title says, what’s the purpose of manifest\_usage.toml?
I have a Julia project that has its own project.toml and manifest.toml. When I try to test this project, I sometimes encounter an error that says:
```julia
Activating project at `/user/project`
┌ Warning: failed to remove pidfile on close
│ path = "/user/.julia/logs/manifest_usage.toml.pid"
│ removed = false
â”” @ FileWatching.Pidfile /user/software/julia-1.9.3/share/julia/stdlib/v1.9/FileWatching/src/pidfile.jl:313
ERROR: LoadError: ArgumentError: number of bytes to checksum must be ≥ 0, got -4
```
A rerun of the test sometimes works, so it’s not reproducible. However, I do see it quite often. How do I resolve it? Is it safe to just delete `manifest_usage.toml`? Thanks for any help!
---
### Author:  [@ericphanson](https://discourse.julialang.org/u/ericphanson)
#### Post date: [November 1, 2023, 1:10am UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/2 "2023-11-01T01:10:32Z")
I think it is used for the Pkg GC system, to know which package versions are being used, and so it can clean up the unused ones after enough time has passed.
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### Author:  [@math\_opt](https://discourse.julialang.org/u/math_opt)
#### Post date: [November 1, 2023, 3:03am UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/3 "2023-11-01T03:03:27Z")
I see. I did suspect this and ran the `Pkg.resolve()` and `Pkg.gc` commands; however, I still see the error every now and then.
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### Author:  [@ericphanson](https://discourse.julialang.org/u/ericphanson)
#### Post date: [November 1, 2023, 11:29am UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/4 "2023-11-01T11:29:36Z")
I haven’t seen this issue with pidfiles for `manifest_usage` before. Might be worth filing an issue, or maybe @ianshmean has an idea
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### Author:  [@ianshmean](https://discourse.julialang.org/u/ianshmean)
#### Post date: [November 1, 2023, 2:16pm UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/5 "2023-11-01T14:16:50Z")
Yeah please file an issue with more info. Also your terminal printing seems off?
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### Author:  [@jling](https://discourse.julialang.org/u/jling)
#### Post date: [November 1, 2023, 2:22pm UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/6 "2023-11-01T14:22:30Z")
I have had similar issues before on a cluster system where home is on network mounted drive…
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### Author:  [@math\_opt](https://discourse.julialang.org/u/math_opt)
#### Post date: [November 1, 2023, 7:39pm UTC](https://discourse.julialang.org/t/what-does-manifest-usage-toml-file-do/105633/7 "2023-11-01T19:39:12Z")
@ianshmean @jling
I am running my script on an HPC cluster too. So that might have something to do with it. Regarding terminal printing, I am not sure why it outputs weird characters randomly. I am using non-interactive nodes on the cluster and they automatically write the output to a text file, which might have something to do with the printing issue. I filed a GitHub issue [here](https://github.com/JuliaLang/julia/issues/51983).