GitLab

Force a full GC after importing a project

Closes #59477

See merge request gitlab-org/gitlab-ce!26803

(cherry picked from commit 57cba4d1)

d4c6a3af Force a full GC after importing a project

`perform_enqueued_jobs` is a Sidekiq method.
Using this method violates the Dependency inversion principle[0].

This commit replaces `perform_enqueued_jobs` with ActiveJob's abstract
method `perform_enqueued_jobs` in specs.

[0]: https://en.wikipedia.org/wiki/Dependency_inversion_principle

This enables skipping a lesser housekeeping task
(incremental or full repack) by consistently
scheduling a higher task (respectively full repack or gc)
with the same period.
Cf. #34981

This reverts commit cb10b725c8929b8b4460f89c9d96c773af39ba6b.

This moves tracking of the pushes since the last Git GC from PostgreSQL
to Redis. This reduces the number of writes on the "projects" table.
This in turn reduces the vacuuming overhead.

The lease used for incrementing the counter has been removed. This lease
was mostly put in place to prevent high database load but this isn't
needed anymore due to the counter now being stored in Redis.

Fixes gitlab-org/gitlab-ce#22125

Due to a stale NFS cache, it's possible that a branch lookup fails
while `git gc` is running and causes missing branches in merge requests.

Possible workaround for #15392