From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: emacs rendering comparisson between emacs23 and emacs26.3 Date: Thu, 02 Apr 2020 16:30:24 +0300 Message-ID: <83zhbuxbf3.fsf@gnu.org> References: <86tv2h2vww.fsf@gmail.com> <20200322123818.GB32470@ACM> <87eetk5swm.fsf@gnu.org> <20200326193128.GC14092@ACM> <86d08y4zsx.fsf@gmail.com> <83sghs7qdz.fsf@gnu.org> <83h7y63sjj.fsf@gnu.org> <834ku43c61.fsf@gnu.org> <83k12zz6ds.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="13997"; mail-complaints-to="usenet@ciao.gmane.io" Cc: acm@muc.de, rrandresf@gmail.com, emacs-devel@gnu.org To: rms@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Apr 02 15:31:39 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 1jJzwZ-0003YC-BG for ged-emacs-devel@m.gmane-mx.org; Thu, 02 Apr 2020 15:31:39 +0200 Original-Received: from localhost ([::1]:38712 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jJzwY-0005SU-8b for ged-emacs-devel@m.gmane-mx.org; Thu, 02 Apr 2020 09:31:38 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:42878) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jJzvl-0004oT-Uo for emacs-devel@gnu.org; Thu, 02 Apr 2020 09:30:50 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:56350) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1jJzvl-0007ur-Ez; Thu, 02 Apr 2020 09:30:49 -0400 Original-Received: from [176.228.60.248] (port=2811 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1jJzvd-0004fM-Mb; Thu, 02 Apr 2020 09:30:42 -0400 In-Reply-To: (message from Richard Stallman on Wed, 01 Apr 2020 22:32:12 -0400) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] 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:246255 Archived-At: > From: Richard Stallman > Cc: acm@muc.de, rrandresf@gmail.com, emacs-devel@gnu.org > Date: Wed, 01 Apr 2020 22:32:12 -0400 > > > I think we do try: patch review frequently has these aspects > > discussed. But it is a well known fact that humans are lousy > > predictors of code speed. > > I'm not suggesting we try to _predict_ the effect on code speed, > rather than we have a guideline to identify the cases where _if_ > the code gets slower it would be hard for a user to escape that. > > What we would do, in those cases, is add a switch to turn off > the changes. Without some efficient method of identifying the cases where this is probable, I fear we will have to add such switches for almost every non-trivial change (and for some trivial ones as well).