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[104.178.186.189]) by smtp.gmail.com with ESMTPSA id a129-20020a0dd887000000b0060a16fb9209sm2340877ywe.115.2024.05.06.13.28.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 May 2024 13:28:41 -0700 (PDT) Date: Mon, 6 May 2024 16:28:40 -0400 From: Taylor Blau To: Jeff King Cc: Junio C Hamano , git@vger.kernel.org, Karthik Nayak , John Cai , Dhruva Krishnamurthy Subject: Re: Re* using tree as attribute source is slow, was Re: Help troubleshoot performance regression cloning with depth: git 2.44 vs git 2.42 Message-ID: References: <20240501220030.GA1442509@coredump.intra.peff.net> <20240503174653.GD3631237@coredump.intra.peff.net> Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20240503174653.GD3631237@coredump.intra.peff.net> On Fri, May 03, 2024 at 01:46:53PM -0400, Jeff King wrote: > On Fri, May 03, 2024 at 08:34:27AM -0700, Junio C Hamano wrote: > > > And for folks who had been happy with the pre 2.42 behaviour, > > we could do something like the attached as the first step to a real fix. > > It looks like lots of discussion happened with out me, and everybody > already posted all of the responses I was going to. Good. :) > > In particular... > > > ----- >8 --------- >8 --------- >8 --------- >8 ----- > > Subject: [PATCH] stop using HEAD for attributes in bare repository by default > > [...] > > The right fix for this is to optimize the code paths that allow > > accesses to attributes in tree objects, but that is a much more > > involved change and is left as a longer-term project, outside the > > scope of this "first step" fix. > > ...this was the exact first step I was going to suggest. And your patch > looks correct to me. I assume you'd target this for 'maint'. The > regression goes back to v2.43.0, so it's not exactly new, but given the > severity in some cases it seems like it's worth getting it into a > release sooner rather than later. For what it's worth, I am in favor of the patch that Junio proposed here. Thanks, Taylor