Re: [PATCH] fetch: download bundles once, even with --all

[Junio C Hamano <gitster@pobox.com>]

"Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Derrick Stolee <derrickstolee@github.com>
>
> When fetch.bundleURI is set, 'git fetch' downloads bundles from the
> given bundle URI before fetching from the specified remote. However,
> when using non-file remotes, 'git fetch --all' will launch 'git fetch'
> subprocesses which then read fetch.bundleURI and fetch the bundle list
> again. We do not expect the bundle list to have new information during
> these multiple runs, so avoid these extra calls by un-setting
> fetch.bundleURI in the subprocess arguments.

It is a good observation, if we assume that all these remotes want
to share the same expectation on what the list of bundles described
in bundleURI should be.

I expected that people use multiple remotes and do a "fetch --all"
before starting work from a cronjob or while fetching coffee first
time in the morning to fetch from repositories holding work from
different folks and manged by different groups, and these groups do
not tightly share the object management recipes at what bundles to
pre-package and list in the list served at a bundleURI.  If there is
such an arrangement between repositires to share the object
management, even if the repositories fetched with the "--all" option
are truly multiple places, it may make sense to assume that these
repositories you are fetching from want you to use the same set of
bundles that are managed the same way to be used.  But I am not sure
if that assumption holds true.

Where does fetch.bundleURI come originally?  If we set only one
globally for the local repository at "git clone" time, perhaps that
is a problem?  IOW, instead of fetch.bundleURI, we would want to
have something per remote, e.g. remote.<name>.bundleURI, instead?

Putting that design level tangent aside, everything I see in this
patch makes sense, assuming that the fetch_bundle_uri() call done
fairly early in the parent process is sufficient to tell the child
processes that deal with individual repositories to reuse the info
that was already retrieved that call.

Thanks.