From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C2AAC433DB for ; Tue, 30 Mar 2021 07:16:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DC51161994 for ; Tue, 30 Mar 2021 07:16:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231187AbhC3HQS (ORCPT ); Tue, 30 Mar 2021 03:16:18 -0400 Received: from cloud.peff.net ([104.130.231.41]:36768 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230415AbhC3HP7 (ORCPT ); Tue, 30 Mar 2021 03:15:59 -0400 Received: (qmail 18132 invoked by uid 109); 30 Mar 2021 07:15:58 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with ESMTP; Tue, 30 Mar 2021 07:15:58 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 22064 invoked by uid 111); 30 Mar 2021 07:15:59 -0000 Received: from coredump.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Tue, 30 Mar 2021 03:15:59 -0400 Authentication-Results: peff.net; auth=none Date: Tue, 30 Mar 2021 03:15:58 -0400 From: Jeff King To: Taylor Blau Cc: git@vger.kernel.org, avarab@gmail.com, dstolee@microsoft.com, gitster@pobox.com, jonathantanmy@google.com Subject: Re: [PATCH v3 16/16] midx.c: improve cache locality in midx_pack_order_cmp() Message-ID: References: <550e785f10ba14f166958501c007b75a04052a0d.1615482270.git.me@ttaylorr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Mon, Mar 29, 2021 at 05:34:21PM -0400, Taylor Blau wrote: > > Did we record any numbers to show the improvement here? I don't think it > > can be demonstrated with this series (since most of the code is dead), > > but I recall that this was motivated by a noticeable slowdown. > > Looking through our messages, you wrote that this seemed to produce a > .8 second speed-up on a large-ish repository that we were testing. > That's not significant overall, the fact that we were spending so long > probably caught our attention when looking at a profiler. That sounds about right from my recollection. > I could go either way on mentioning it. It does feel a little like > cheating to say, "well, if you applied these other patches it would make > it about this much faster". So I'm mostly happy to just keep it vague > and say that it makes things a little faster, unless you feel strongly > otherwise. No, I don't feel strongly. I just wanted to give people reading a sense of what to expect. Now we have. -Peff