From: Derrick Stolee <stolee@gmail.com>
Date: Fri, 05 Oct 2018 20:00:12 GMT
Subject: Re: [RFC PATCH] We should add a "git gc --auto" after "git clone" due to commit graph
Message-ID: <14529aaa-fee0-e839-4629-bf87cdd13e31@gmail.com>
In-Reply-To: <20181005194703.GA19735@sigill.intra.peff.net>

On 10/5/2018 3:47 PM, Jeff King wrote:
> On Fri, Oct 05, 2018 at 03:41:40PM -0400, Derrick Stolee wrote:
>
>>> So can we really just take (total_objects - commit_graph_objects) and
>>> compare it to some threshold?
>> The commit-graph only stores the number of _commits_, not total objects.
> Oh, right, of course. That does throw a monkey wrench in that line of
> thought. ;)
>
> There's unfortunately not a fast way of doing that. One option would be
> to keep a counter of "ungraphed commit objects", and have callers update
> it. Anybody admitting a pack via index-pack or unpack-objects can easily
> get this information. Commands like fast-import can do likewise, and
> "git commit" obviously increments it by one.
>
> I'm not excited about adding a new global on-disk data structure (and
> the accompanying lock).

If we want, then we can add an optional chunk to the commit-graph file 
that stores the object count.