From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#15555: 24.3; Bidirectional display very slow with long lines Date: Wed, 09 Oct 2013 19:59:26 +0300 Message-ID: <83iox6qt1t.fsf@gnu.org> References: <83wqlo461e.fsf@gnu.org> <8338obskk4.fsf@gnu.org> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1381338024 18768 80.91.229.3 (9 Oct 2013 17:00:24 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 9 Oct 2013 17:00:24 +0000 (UTC) Cc: jlquinn@us.ibm.com, 15555@debbugs.gnu.org To: Stefan Monnier Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed Oct 09 19:00:25 2013 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1VTx7R-0000By-PP for geb-bug-gnu-emacs@m.gmane.org; Wed, 09 Oct 2013 19:00:17 +0200 Original-Received: from localhost ([::1]:42909 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTx7R-0005ni-EI for geb-bug-gnu-emacs@m.gmane.org; Wed, 09 Oct 2013 13:00:17 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:51832) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTx7I-0005hl-W6 for bug-gnu-emacs@gnu.org; Wed, 09 Oct 2013 13:00:14 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VTx7D-0001Gi-R2 for bug-gnu-emacs@gnu.org; Wed, 09 Oct 2013 13:00:08 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:58058) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTx7D-0001Fb-FZ for bug-gnu-emacs@gnu.org; Wed, 09 Oct 2013 13:00:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1VTx7C-0000du-LG for bug-gnu-emacs@gnu.org; Wed, 09 Oct 2013 13:00:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 09 Oct 2013 17:00:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 15555 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 15555-submit@debbugs.gnu.org id=B15555.13813379722390 (code B ref 15555); Wed, 09 Oct 2013 17:00:02 +0000 Original-Received: (at 15555) by debbugs.gnu.org; 9 Oct 2013 16:59:32 +0000 Original-Received: from localhost ([127.0.0.1]:38115 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VTx6h-0000cT-FG for submit@debbugs.gnu.org; Wed, 09 Oct 2013 12:59:31 -0400 Original-Received: from mtaout20.012.net.il ([80.179.55.166]:43170) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1VTx6e-0000cJ-Vb for 15555@debbugs.gnu.org; Wed, 09 Oct 2013 12:59:30 -0400 Original-Received: from conversion-daemon.a-mtaout20.012.net.il by a-mtaout20.012.net.il (HyperSendmail v2007.08) id <0MUE00100V129T00@a-mtaout20.012.net.il> for 15555@debbugs.gnu.org; Wed, 09 Oct 2013 19:59:27 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout20.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0MUE0001VV72RJD0@a-mtaout20.012.net.il>; Wed, 09 Oct 2013 19:59:26 +0300 (IDT) In-reply-to: X-012-Sender: halo1@inter.net.il X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:79094 Archived-At: > From: Stefan Monnier > Cc: Jerome L Quinn , 15555@debbugs.gnu.org > Date: Wed, 09 Oct 2013 08:26:58 -0400 > > >> And disabling bidi reordering completely eliminates the bad behavior. > > If you can afford that, go for it. > > IIRC this is the first report where setting bidi-display-reordering to > nil is really the best recommendation we can offer (and where it > apparently indeed helps significantly). Actually, it's not my recommendation. But the OP keeps claiming that nothing else works for him. My recommendation would be rather to make lines shorter. > I consider bidi-display-reordering as a debugging tool rather than > a user config, so I'm not very happy about this situation. I'm not happy either (probably even less than you), but I'm not going to agree that slow redisplay of 14K-character lines has anything to do with bidirectional editing support. _Anything_ that slows down redisplay even a bit will have the same effect with such long lines, e.g., JIT font lock, Flyspell, invisible text, you name it. In fact, even on a reasonably fast machine (mine is a core i7 screamer) Emacs is unbearably slow with such long lines without reordering as well. Maybe the OP has an unreasonably fast machine, but that just makes his use case even more rare. IOW, this is bug #13675, which has nothing to do with bidi. As long as the basic display algorithms are not changed to fix that bug, I'm going to claim that bidi is not the issue here.