From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Is Emacs buffer scroll/redisplay slow? Date: Sun, 19 Jan 2020 17:20:53 -0500 Message-ID: References: <20200119115146.GA9172@ACM> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="30191"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: Alan Mackenzie , Emacs developers To: Fabrice Popineau Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Jan 19 23:21:40 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 1itIwt-0007nq-K0 for ged-emacs-devel@m.gmane-mx.org; Sun, 19 Jan 2020 23:21:39 +0100 Original-Received: from localhost ([::1]:54094 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1itIws-00053j-M7 for ged-emacs-devel@m.gmane-mx.org; Sun, 19 Jan 2020 17:21:38 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:50219) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1itIwF-0004bf-BU for emacs-devel@gnu.org; Sun, 19 Jan 2020 17:21:00 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1itIwE-00052N-0a for emacs-devel@gnu.org; Sun, 19 Jan 2020 17:20:58 -0500 Original-Received: from mailscanner.iro.umontreal.ca ([132.204.25.50]:60882) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1itIwD-00051Y-Su for emacs-devel@gnu.org; Sun, 19 Jan 2020 17:20:57 -0500 Original-Received: from pmg2.iro.umontreal.ca (localhost.localdomain [127.0.0.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id 75B5281184; Sun, 19 Jan 2020 17:20:56 -0500 (EST) Original-Received: from mail01.iro.umontreal.ca (unknown [172.31.2.1]) by pmg2.iro.umontreal.ca (Proxmox) with ESMTP id EBC4680077; Sun, 19 Jan 2020 17:20:54 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=iro.umontreal.ca; s=mail; t=1579472454; bh=KZCV4TBxerRno88IXvN0QIm64HTHht4J6hINcKFICSI=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=meAo4zmIAY6FjixGmVnUUYSo7qs5J21KzTBwb4s4yVsOgZl3M5cKewwwl4Vj1ee8O Y+nVh9gNRtfpIbQ1ZUcroaHXJausp+U47NlxH/l1VMQTpi3e3fcbxvesG9LNtgW3Eo 7CtO1by/Z5Kn4JQM4A4sWDjgovh00Wltx3Y7Y2dCBkkSM00BWp5w3I9nQ1dpbqhg8w 1snGdJ0WnPiql4sCwt6Awo7z/S2YfnYJc8kaB9/jX/3pBOgd3y/X6LK3FUyyMngB0k cGp6zQMsDavHDA5EHeOw6UTwBSTdgngxFgK67b4kgDKs7bjVCN7TbMNzMITLvA3tDB pWDCvNkW+NHCA== Original-Received: from pastel (unknown [45.72.156.100]) by mail01.iro.umontreal.ca (Postfix) with ESMTPSA id B47DB120EBE; Sun, 19 Jan 2020 17:20:54 -0500 (EST) In-Reply-To: (Fabrice Popineau's message of "Sun, 19 Jan 2020 15:24:19 +0100") X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 132.204.25.50 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:244395 Archived-At: >> > .... scrolling through an elisp buffer: I started the timer by hand and >> > scrolled down for 1000 lines .... [...] >> .... and it took 45s on Windows/WSL and 35s on Windows/native. 1000 lines divided by 45s is about 22 lines per second. If you did that with `C-n` it suggests you're simply using a keyboard repeat rate of about 20 repetitions-per-second and Emacs is just neither fast nor slow. 35s on native suggests the keyboard repeat rate is (surprisingly) different, more like 30 repetitions-per-second. If Emacs is slow in such a test, you'll notice because it will stop refreshing the display at times (hoping that skipping the redisplay time will help it keep up with the repeat rate). Stefan