Re: [PATCH 2/2] fetch-pack: respect --no-update-shallow in v2

[Jeff King <peff@peff.net>]

On Tue, Mar 26, 2019 at 05:14:11PM +0700, Duy Nguyen wrote:

> > That seems like the best we can do without the protocol change. And even
> > if we adjust the protocol, we need some fallback behavior for existing
> > v2 servers, so this is worth doing.
> 
> Are people actually doing this (i.e. cloning from or  pushing to a
> shallow repo)? I added this with the intention that a big shallow repo
> (e.g. one year long history) is served as the common source to reduce
> server loads and everything, while the full/big repo is available but
> rarely needed. I never saw anyone complain about it (so, likely not
> using it).

I don't think I've ever seen anybody serve fetches out of a shallow
clone in practice (I don't think we ever seriously considered them at
GitHub, but given their general incompatibility with reachability
bitmaps, I suspect it would cause more performance problems than it
solves).

I've always imagined people do it for one-offs. E.g., they have a
shallow clone, and fetch out of that to a temporary copy. That may be
less useful these days with the advent of separate worktrees.

-Peff