From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Ulrich Mueller Newsgroups: gmane.emacs.devel Subject: Re: Scrolling xdisp.c. Room for optimisation in syntax.c/CC Mode. Date: Sun, 19 Oct 2014 18:37:26 +0200 Message-ID: <21571.59590.312221.336635@a1i15.kph.uni-mainz.de> References: <20141018181937.GA5924@acm.acm> <20141018202839.GB5924@acm.acm> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1413738597 16976 80.91.229.3 (19 Oct 2014 17:09:57 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 19 Oct 2014 17:09:57 +0000 (UTC) Cc: emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Oct 19 19:09:51 2014 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XftzK-0002Cz-4F for ged-emacs-devel@m.gmane.org; Sun, 19 Oct 2014 19:09:50 +0200 Original-Received: from localhost ([::1]:40656 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XftzJ-0005Eu-N3 for ged-emacs-devel@m.gmane.org; Sun, 19 Oct 2014 13:09:49 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:42743) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xftyx-00052b-6j for emacs-devel@gnu.org; Sun, 19 Oct 2014 13:09:34 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xftyp-0005A0-F5 for emacs-devel@gnu.org; Sun, 19 Oct 2014 13:09:27 -0400 Original-Received: from a1www.kph.uni-mainz.de ([134.93.134.1]:38698) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xftyp-00057z-3S for emacs-devel@gnu.org; Sun, 19 Oct 2014 13:09:19 -0400 Original-Received: from a1i15.kph.uni-mainz.de (a1i15.kph.uni-mainz.de [134.93.134.92]) by a1www.kph.uni-mainz.de (8.14.9/8.14.7) with ESMTP id s9JGbRxH025256; Sun, 19 Oct 2014 18:37:27 +0200 Original-Received: from a1i15.kph.uni-mainz.de (localhost [127.0.0.1]) by a1i15.kph.uni-mainz.de (8.14.8/8.14.2) with ESMTP id s9JGbQ8x027198; Sun, 19 Oct 2014 18:37:26 +0200 Original-Received: (from ulm@localhost) by a1i15.kph.uni-mainz.de (8.14.8/8.14.8/Submit) id s9JGbQDa027194; Sun, 19 Oct 2014 18:37:26 +0200 In-Reply-To: <20141018202839.GB5924@acm.acm> X-Mailer: VM 8.2.0b under 24.3.1 (x86_64-pc-linux-gnu) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 134.93.134.1 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:175565 Archived-At: >>>>> On Sat, 18 Oct 2014, Alan Mackenzie wrote: > I've just repeated the measurement on the Emacs trunk, with emacs -Q. I > now get these results: > no-odd-xdisp.c: 500 scrolls, total time = 104.21487808227539s. > xdisp.c: 500 scrolls, total time = 167.73530864715576s. > I don't know why there are more scroll operations needed. But the fact > that scrolling is taking two and a half times longer in the trunk than in > 24..3 is noteworthy, and possibly disturbing. I'm think I compiled both > version with the same optimisation level, etc. I don't see such a large degradation of performance between 24.3 and trunk here. no-odd-xdisp.c: 22.3: 415 scrolls, total time = 14.469409942626953s. 23.4: 415 scrolls, total time = 14.116178750991821s. 24.3: 415 scrolls, total time = 45.48526978492737s. 24.4-rc1: 415 scrolls, total time = 44.03023886680603s. 25.0.50: 415 scrolls, total time = 45.08613348007202s. xdisp.c: 22.3: 415 scrolls, total time = 14.692334413528442s. 23.4: 415 scrolls, total time = 14.051368474960327s. 24.3: 415 scrolls, total time = 50.858959674835205s. 24.4-rc1: 415 scrolls, total time = 58.63706636428833s. 25.0.50: 415 scrolls, total time = 59.3416690826416s. Tests were done with emacs -Q -nw in an xterm, 80 columns times 80 lines. (What causes the big slowdown from 23.4 to 24.3, though?) Ulrich