From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stephen Berman Newsgroups: gmane.emacs.devel Subject: Re: The Emacs master is much slower than the emacs-27 branch. Date: Fri, 04 Dec 2020 11:14:36 +0100 Message-ID: <878sadsws3.fsf@gmx.net> References: <877dpyzg9d.fsf@rub.de> <87czzpsyqn.fsf@gmx.net> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="6066"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Dec 04 11:16:03 2020 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kl88B-0001T7-9f for ged-emacs-devel@m.gmane-mx.org; Fri, 04 Dec 2020 11:16:03 +0100 Original-Received: from localhost ([::1]:36980 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kl88A-00082b-CI for ged-emacs-devel@m.gmane-mx.org; Fri, 04 Dec 2020 05:16:02 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:54998) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kl86z-0007TP-V4 for emacs-devel@gnu.org; Fri, 04 Dec 2020 05:14:49 -0500 Original-Received: from mout.gmx.net ([212.227.15.15]:51029) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kl86x-00005q-W5 for emacs-devel@gnu.org; Fri, 04 Dec 2020 05:14:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1607076885; bh=Wk1HtOtCoQFeSY5WVERdMmR/vWQOjhwUkn9CC1tJCO0=; h=X-UI-Sender-Class:From:To:Cc:Subject:References:Date:In-Reply-To; b=H3GgpYYNB05CruY5imVrx4FIlOAAfw13UcBLiLz5V637BFz2L8klz6Tg4H8wKnI+S +oWtbjF1tm2mVjf0BotctwYdN2otyOR20/+QcNgMpBfvQ8vtANkC10DcI/JxnQi0dQ e6TyKW9x1Il6DDirxKzWyRJuzg9y6KzxozmN8uoA= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Original-Received: from strobe-jhalfs ([178.6.218.210]) by mail.gmx.com (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1MtwZ4-1jtQYy2yWi-00uKGJ; Fri, 04 Dec 2020 11:14:44 +0100 In-Reply-To: (Alan Mackenzie's message of "Fri, 4 Dec 2020 09:53:40 +0000") X-Provags-ID: V03:K1:tDdCgG86dzZLVBVRGtc4CLtqkMpoNUOk/7SUfdXu7RSLDNkuM7f rCXuZqUByy5VYJLC06BdziwlI1fw03MD0RIUG7v8WwN59XAQYH7IdIvVNREDIi0Jys83w+W CwFMu2+1eWR+UQMEspAcv1xWSfxgN10xBHNrXlI5pk/vDo8XLpdQuR0nnCiqStTPJG1wtk0 aUVoL+0zgs+N2JFAzwHkA== X-UI-Out-Filterresults: notjunk:1;V03:K0:E38YdkbrxiM=:33cifFI+I5sRHN3kz2Q7bh 6IWBmr1U/kZc71c2Cf1p/Dd+i2KDdBpzUYGbgbeg6gfMoTwO8Co9eirogXhd1UTGcPz9Xf+0z raSYzjojWQDE2tSKXMVGHQN3wdFyBXrZt5htLmvoQoiGzetRTVTTmzF/GncDEwv2DkLW58fDw eHEK0MamYS+4I9YrTfCiPIzdT+hR46c3zSJYGDkzTiycrwlGtCLDZuoGUYdJXlbBgT/IklCNB WxdQVx01hlq9+AWehaMkMRg4vRDaLkn0gPvust5eMY/YGsoiw384zEuIBxxEOwY4fd+/znM4N QL4APu1flteto2fResNpjvJjAxn53Fk8ZMICNkOOnf5JJEYtNZFYqkSf/Q8/1TSf2aT8VOCM1 AedX7hTJ62iJ3kHo3s/HjQdHYK1hzAjJeZtzVfvPkSrPA54FbyNMR/N2d80rTVLkzoL5yO9cn 3294ADJ9R9DPx06hojnMOf69N3cH1YjdjGj+YN23Ef9ce5xlNX0lx9hMsQ8koSXrWLDgtndlc bqAXkH6yfnLxhEUMn096jFid07G1ncBSvcwVXGrqwqyMTa3fs6O9FY4M/Ia9ZDYJSQQ/YsCxB vfx0Xv4tsYnd4945bjiExoDQar27wn46Fqo2jxwAqbYVuozYVkhcJ6W0w70SZWXx6iFqP24Ub NKLVFd998BdUbw/jv0mYhs5dwfMpbyctERdIzzf7I5+yErJbEBbOuV8aunNGvwB/XjZeBwhE2 KuqNlIuH8d1TNtG5mFCGiy3+IupEnoZmIefj+0exuqpLKFlTmGS17DCcqyLyvV9i5jW9JAmy Received-SPF: pass client-ip=212.227.15.15; envelope-from=stephen.berman@gmx.net; helo=mout.gmx.net X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:260284 Archived-At: On Fri, 4 Dec 2020 09:53:40 +0000 Alan Mackenzie wrote: > Hello, Steve. > > On Fri, Dec 04, 2020 at 10:32:16 +0100, Stephen Berman wrote: >> On Fri, 4 Dec 2020 09:04:49 +0000 Alan Mackenzie wrote: >> > On Thu, Dec 03, 2020 at 23:17:18 +0100, Stephen Berman wrote: >> >> On Thu, 3 Dec 2020 18:15:30 +0000 Alan Mackenzie wrote: > >> >> > Hello, Emacs. > >> >> > I've got pretty much up to date copies of both the master and the >> >> > emacs-27 branches. > >> >> > When I run my customary benchmark (see below) on master's src/xdisp.c in >> >> > master, it's taking around 34s. On emacs-27, it's taking 22s. > >> >> Hm, this is odd: I just ran your benchmark on src/xdisp.c (starting >> >> Emacs with -Q, both configured with CFLAGS='-Og -g3') and got vastly >> >> different timings than you did: > >> >> master: 21.785817861557007 >> >> emacs-27: 61.3885281085968 > >> > Maybe the emacs-27 is built without optimisation for debugging. > >> As noted above, I build both master and emacs-27 with CFLAGS='-Og -g3'. > > Apologies. I hadn't read your post properly. > >> Given that, is such a difference still expected? Eli wrote: >> "In unoptimized builds I get almost no difference: Emacs 28 is about 4% >> slower than Emacs 27", which also contrasts sharply with my timings. > > I can't understand why you're getting such a slowdown in your emacs-27. > You've presumably got a modern machine, with plenty of cores and plenty > of RAM, so it shouldn't be swapping, or some other process taking up the > processor. The CPU is an i7-8700 with 6 cores (12 threads) and 16 GB RAM. I ran the benchmarks twice in sequence, first using xdisp.c from master and then using xdisp.c from emacs-27, with nearly identical results (with the latter the timings were insignificantly faster, but the differences between the runs from master and those from emacs-27 were the same). > There's something very strange happening. Indeed. Steve Berman