From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Long lines and bidi Date: Sun, 10 Feb 2013 18:57:00 +0200 Message-ID: <83r4ko5cpv.fsf@gnu.org> References: <877gmp5a04.fsf@ed.ac.uk> <83vca89izh.fsf@gnu.org> <5110906D.7020406@yandex.ru> <83fw1aac3d.fsf@gnu.org> <51120360.4060104@yandex.ru> <51127363.5030203@yandex.ru> <834nhp9u9j.fsf@gnu.org> <5114FEBB.8020201@yandex.ru> <838v6y99wk.fsf@gnu.org> <836222983u.fsf@gnu.org> <51152A00.6070101@yandex.ru> <83y5ey7npl.fsf@gnu.org> <5115C3BC.8020203@cs.ucla.edu> <83txpl7u3w.fsf@gnu.org> <5116113D.5070707@cs.ucla.edu> <83mwvd7qlx.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1360515419 27892 80.91.229.3 (10 Feb 2013 16:56:59 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 10 Feb 2013 16:56:59 +0000 (UTC) Cc: emacs-devel@gnu.org To: eggert@cs.ucla.edu, dmantipov@yandex.ru Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Feb 10 17:57:20 2013 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 1U4aDQ-0005tg-2Y for ged-emacs-devel@m.gmane.org; Sun, 10 Feb 2013 17:57:20 +0100 Original-Received: from localhost ([::1]:41605 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U4aD6-00045O-KZ for ged-emacs-devel@m.gmane.org; Sun, 10 Feb 2013 11:57:00 -0500 Original-Received: from eggs.gnu.org ([208.118.235.92]:40210) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U4aD4-00045J-GH for emacs-devel@gnu.org; Sun, 10 Feb 2013 11:56:59 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1U4aD3-0002ah-A9 for emacs-devel@gnu.org; Sun, 10 Feb 2013 11:56:58 -0500 Original-Received: from mtaout20.012.net.il ([80.179.55.166]:50151) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U4aD3-0002aZ-25 for emacs-devel@gnu.org; Sun, 10 Feb 2013 11:56:57 -0500 Original-Received: from conversion-daemon.a-mtaout20.012.net.il by a-mtaout20.012.net.il (HyperSendmail v2007.08) id <0MI000500KDP6600@a-mtaout20.012.net.il> for emacs-devel@gnu.org; Sun, 10 Feb 2013 18:56:55 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout20.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0MI00048VKEUPFA0@a-mtaout20.012.net.il>; Sun, 10 Feb 2013 18:56:55 +0200 (IST) In-reply-to: <83mwvd7qlx.fsf@gnu.org> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: Solaris 10 X-Received-From: 80.179.55.166 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:156946 Archived-At: > Date: Sat, 09 Feb 2013 12:01:46 +0200 > From: Eli Zaretskii > Cc: dmantipov@yandex.ru, emacs-devel@gnu.org > > That is why I think we should attack this problem one reason at a > time. The most important reason is the first one: long lines cause > the display code traverse too much of buffer text. This is why you > see x_produce_glyphs so high on the profile in the unidirectional > case: it examines too many characters, much more than what will be > actually displayed on the screen. I just committed to the trunk revision 111724 with a couple of simple changes which speed up by a factor of 3 some redisplay operations, such as M-v or M->, in a buffer with very long lines. Please try it. This is by no means the complete solution, even for the situations where it provides a 3-fold speed-up: we need the speed-up to be much more aggressive. But it does demonstrate how simple changes can have a significant effect in this area. Stay tuned.