From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: The Emacs master is much slower than the emacs-27 branch. Date: Fri, 4 Dec 2020 09:53:40 +0000 Message-ID: References: <877dpyzg9d.fsf@rub.de> <87czzpsyqn.fsf@gmx.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="30650"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: Stephen Berman Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Dec 04 10:54:36 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 1kl7nQ-0007uD-EE for ged-emacs-devel@m.gmane-mx.org; Fri, 04 Dec 2020 10:54:36 +0100 Original-Received: from localhost ([::1]:46566 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kl7nP-00075Q-Ey for ged-emacs-devel@m.gmane-mx.org; Fri, 04 Dec 2020 04:54:35 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:47610) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kl7md-0006OX-7I for emacs-devel@gnu.org; Fri, 04 Dec 2020 04:53:47 -0500 Original-Received: from colin.muc.de ([193.149.48.1]:49975 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1kl7mZ-0000Id-SN for emacs-devel@gnu.org; Fri, 04 Dec 2020 04:53:46 -0500 Original-Received: (qmail 61417 invoked by uid 3782); 4 Dec 2020 09:53:41 -0000 Original-Received: from acm.muc.de (p4fe158a9.dip0.t-ipconnect.de [79.225.88.169]) by localhost.muc.de (tmda-ofmipd) with ESMTP; Fri, 04 Dec 2020 10:53:40 +0100 Original-Received: (qmail 4350 invoked by uid 1000); 4 Dec 2020 09:53:40 -0000 Content-Disposition: inline In-Reply-To: <87czzpsyqn.fsf@gmx.net> X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de Received-SPF: pass client-ip=193.149.48.1; envelope-from=acm@muc.de; helo=mail.muc.de X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, 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:260281 Archived-At: 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. There's something very strange happening. > Steve Berman -- Alan Mackenzie (Nuremberg, Germany).