From: Junio C Hamano Date: Mon, 02 Mar 2026 18:54:19 GMT Subject: Re: Performance regression in "update" hooks Message-ID: In-Reply-To: <87wlzu5cug.fsf@collabora.com> Adrian Ratiu writes: > On Mon, 02 Mar 2026, Jeff King wrote: >> On Mon, Mar 02, 2026 at 03:27:22PM +0100, Patrick Steinhardt wrote: >> >>> > > I don't have the benchmark setup and it might be easier for you to >>> > > confirm? >>> >>> All you need is a normal development infra and hyperfine. The >>> benchmarking scripts in the repo I linked should then "just work" with >>> the above invocation. >> >> Thanks, these were very cool and easy to use. >> >> Looking at the patch, my guess was that the problem is that we are now >> setting up and tearing down the sideband muxer for each hook invocation. >> This is expensive for the "update" hook, since it fires once per ref. > > I independently root caused it and came up with (mostly) the same fix, > so this is a very good confirmation, thanks! > > Please wait for my patch because it needs fixing it 3 places, for 3 > hooks which spin up/down no-op async threads. :) Thanks for working on the problem report and coming to a fix so quickly.