From: Jeff King <peff@peff.net>
Date: Fri, 01 Jul 2022 18:21:50 GMT
Subject: Re: How to reduce pickaxe times for a particular repo?
Message-ID: <Yr87Pt8/l2Tte/Gd@coredump.intra.peff.net>
In-Reply-To: <6439e948-ff79-9e10-97f5-378806e25b5b@github.com>

On Tue, Jun 28, 2022 at 09:01:17AM -0400, Derrick Stolee wrote:

> > Typically, a `git log -S/-G` lookup takes around a minute to complete.
> > I would like to significantly reduce that time. How can I do that? I
> > can spend up to 10x more disk space, if required. The machine has 10
> > cores and 32GB of RAM.
> 
> You are using -S<string> or -G<regex> to see which commits change the
> number of matches of that <string> or <regex>. If you don't provide a
> pathspec, then Git will search every changed file, including those
> very large binary files.
> 
> Perhaps you'd like to start by providing a pathspec that limits the
> search to only the meaningful code files?

I think "-S" will search every file, since it's just counting instances
of the token in each file. But "-G" does a diff first, so it skips
binary files. So you could probably speed it up in general with a
.gitattributes that mark large binary files as such. Sort of the same
concept as your pathspec suggestion (which is a good one), but you don't
have to remember to add it to each invocation. :)

-Peff