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: The Emacs master is much slower than the emacs-27 branch. Date: Thu, 3 Dec 2020 18:15:30 +0000 Message-ID: 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="22406"; mail-complaints-to="usenet@ciao.gmane.io" To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Dec 03 19:23:23 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 1kktGF-0005iY-8a for ged-emacs-devel@m.gmane-mx.org; Thu, 03 Dec 2020 19:23:23 +0100 Original-Received: from localhost ([::1]:49370 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kktGE-0008Gw-Ae for ged-emacs-devel@m.gmane-mx.org; Thu, 03 Dec 2020 13:23:22 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:39748) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kkt8j-0003ep-NZ for emacs-devel@gnu.org; Thu, 03 Dec 2020 13:15:37 -0500 Original-Received: from colin.muc.de ([193.149.48.1]:11345 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1kkt8g-00040Q-Fq for emacs-devel@gnu.org; Thu, 03 Dec 2020 13:15:37 -0500 Original-Received: (qmail 35729 invoked by uid 3782); 3 Dec 2020 18:15:30 -0000 Original-Received: from acm.muc.de (p4fe159c7.dip0.t-ipconnect.de [79.225.89.199]) by localhost.muc.de (tmda-ofmipd) with ESMTP; Thu, 03 Dec 2020 19:15:30 +0100 Original-Received: (qmail 9540 invoked by uid 1000); 3 Dec 2020 18:15:30 -0000 Content-Disposition: inline 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:260235 Archived-At: 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. That's a massive slowdown. Does anybody know why this is happening? Should I raise a bug report? The benchmark I run is this: (defmacro time-it (&rest forms) "Time the running of a sequence of forms using `float-time'. Call like this: \"M-: (time-it (foo ...) (bar ...) ...)\"." `(let ((start (float-time))) ,@forms (- (float-time) start))) (defun time-scroll (&optional arg) (interactive "P") (message "%s" (time-it (condition-case nil (while t (if arg (scroll-down) (scroll-up)) (sit-for 0)) (error nil))))) On a freshly loaded buffer, do M-: (time-scroll). -- Alan Mackenzie (Nuremberg, Germany).