Re: [PATCH] fetch: choose a sensible default with --jobs=0 again

"Matthias Aßhauer via GitGitGadget"  [off-list ref]
writes:

From: =?UTF-8?q?Matthias=20A=C3=9Fhauer?= <redacted>

prior to 51243f9 (run-command API: don't fall back on online_cpus(),
2022-10-12) `git fetch --multiple --jobs=0` would choose some default amount
of jobs, similar to `git -c fetch.parallel=0 fetch --multiple`. While our
documentation only ever promised that `fetch.parallel` would fall back to a
"sensible default", it makes sense to do the same for `--jobs`. So fall back
to online_cpus() and not BUG() out.

Yup, the way I read 51243f9f (run-command API: don't fall back on
online_cpus(), 2022-10-12) is that it wanted to make it a best
practice for the callers of the API to be making an explicit choice
of scaling with online_cpus() or other metrics depending on their
needs.  The problematic commit does touch some fetch-related code
paths and make them call online_cpus() themselves, so we probably
are looking at an inadequate tests, and this is a fix that is in
line of the spirit, completing what 51243f9f started to do.

Thanks, will queue.