From: Jeff King <peff@peff.net>
Date: Wed, 07 Oct 2020 15:39:47 GMT
Subject: Re: [ANNOUNCE] Git v2.29.0-rc0
Message-ID: <20201007153947.GA181281@coredump.intra.peff.net>
In-Reply-To: <xmqqa6x070tn.fsf@gitster.c.googlers.com>

On Mon, Oct 05, 2020 at 03:41:24PM -0700, Junio C Hamano wrote:

>  * "git index-pack" learned to resolve deltified objects with greater
>    parallelism.

I noticed a small regression in v2.29 today: we no longer seem to show
progress during the delta resolution phase of index-pack.

E.g., try this in a clone of git.git (or really any decent-sized repo
where the delta resolution takes a few seconds):

  # simulate the pack we'd get from a clone or big fetch
  git pack-objects --all --stdout >foo.pack </dev/null

  # now simulate the index-pack on the receiving side
  rm -rf repo
  git init repo &&
  (cd repo && git index-pack -v --stdin <../foo.pack)

You should see the:

  Receiving objects: 100% (300970/300970), 74.39 MiB | 57.93 MiB/s, done.

progress. We used to follow that with:

  Resolving deltas: 100% (249340/249340), done.

but now you get nothing for several seconds while we resolve deltas.

The problem bisects to f08cbf60fe (index-pack: make quantum of work
smaller, 2020-09-08) at the tip of jt/threaded-index-pack. I haven't dug
further yet.

-Peff