Git lock failure

[kit-ty-kate]

Building on cree.ocamllabs.io
fatal: Unable to create '/var/cache/obuilder/ocluster/git/opam-repository.git-b322f7b18d276db68487afc3dfc5a5befdd45818/.git/index.lock': File exists.

Another git process seems to be running in this repository, e.g.
an editor opened by 'git commit'. Please make sure all processes
are terminated then try again. If it still fails, a git process
may have crashed in this repository earlier:
remove the file manually to continue.
git-reset failed with exit-code 128

e.g. https://opam.ci.ocaml.org/github/ocaml/opam-repository/commit/fac594542e6e3fb469687d23f9ebe25982ab36c7/variant/opam-2.0,compilers,4.12,solo5-elftool.0.1.0

[talex5]

Probably just this again: ocurrent/ocluster#115

[kit-ty-kate]

It happened again: https://opam.ci.ocaml.org/github/ocaml/opam-repository/commit/05d575c1fe9cac3e1fd717d61936a03d27d7e68b/variant/opam-2.1,extras,nnp,libbinaryen.104.0.0

[tmcgilchrist]

And again https://opam.ci.ocaml.org/github/ocaml/opam-repository/commit/c58c3f18c25359b70e1c8d7e00a5cd6530287fe0/variant/macos,macos-homebrew-ocaml-4.14-arm64,tezt.3.0.0

2023-01-03 16:49.20: Waiting for resource in pool OCluster
2023-01-03 21:17.58: Waiting for worker…
2023-01-04 00:01.23: Got resource from pool OCluster
Building on m1-worker-01
All commits already cached
fatal: Unable to create '/private/var/lib/ocluster-worker/git/opam-repository.git-b322f7b18d276db68487afc3dfc5a5befdd45818/.git/index.lock': File exists.

Another git process seems to be running in this repository, e.g.
an editor opened by 'git commit'. Please make sure all processes
are terminated then try again. If it still fails, a git process
may have crashed in this repository earlier:
remove the file manually to continue.
git-reset failed with exit-code 128
2023-01-04 00:01.23: Job failed: Failed: Build failed

[kit-ty-kate]

See also ocurrent/opam-repo-ci#202 (comment)

@talex5 are we using Lwt.cancel for anything at this level?

[talex5]

@talex5 are we using Lwt.cancel for anything at this level?

Unlikely. I try to avoid it.

But I don't see what this issue has to do with OBuilder anyway. OCluster only passes a temporary copy of the git repository to OBuilder, so if it's broken then it's OCluster's fault (e.g. ocurrent/ocluster#115).