Re: [PATCH 0/9] send-email: various optimizations to speed up by >2x

From: Jeff King <peff@peff.net>
Date: May 12, 2021, 23:36 UTC
Message-ID: <YJxmmyM9/3KBFPTg@coredump.intra.peff.net>
In-Reply-To: <cover-0.9-0000000000-20210512T132955Z-avarab@gmail.com>

On Wed, May 12, 2021 at 03:48:16PM +0200, Ævar Arnfjörð Bjarmason wrote:

Show 7 quoted lines

> As noted in the subject this speeds up git-send-email invocations by
> ~2x or more, and brings the very slow t9001 test from running in ~26s
> on my box to ~12s. It's no longer consistently the slowest test I run.
> 
> This is basically done in two ways: We lazily invoke "git config" to
> get config, before it's very eager, and deferring Perl compilation
> with s/use/require/g.

Splitting my reply, since the other one got deep into test-suite timing details.

The techniques here look overall pretty reasonable. I think the module lazy-loading makes the overall code a _little_ uglier, but IMHO the speedup you're getting is worth it (I was surprised how much of the improvement comes from that versus avoiding git-config subprocesses).

My only concern is changing the interface of Git::config_regexp() in the final patch. Do we need to have a config_regexp_with_values() to avoid breaking third-party users of the module?

-Peff