From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.bugs Subject: bug#20404: 25.0.50; Sometimes no fontification with jit-lock-defer-time Date: Wed, 22 Apr 2015 13:37:13 -0400 Message-ID: References: <87a8y0iji1.fsf@gnu.org> <20150422163110.68601.qmail@mail.muc.de> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1429724302 18860 80.91.229.3 (22 Apr 2015 17:38:22 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 22 Apr 2015 17:38:22 +0000 (UTC) Cc: 20404@debbugs.gnu.org, Tassilo Horn To: Alan Mackenzie Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Wed Apr 22 19:38:11 2015 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 1YkybB-0000d5-4L for geb-bug-gnu-emacs@m.gmane.org; Wed, 22 Apr 2015 19:38:09 +0200 Original-Received: from localhost ([::1]:36392 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YkybA-0007bW-Fo for geb-bug-gnu-emacs@m.gmane.org; Wed, 22 Apr 2015 13:38:08 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:50128) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ykyb7-0007bO-QF for bug-gnu-emacs@gnu.org; Wed, 22 Apr 2015 13:38:06 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Ykyb4-0000T6-Qy for bug-gnu-emacs@gnu.org; Wed, 22 Apr 2015 13:38:05 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:46966) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ykyb4-0000T0-OA for bug-gnu-emacs@gnu.org; Wed, 22 Apr 2015 13:38:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1Ykyb4-0007C2-Gz for bug-gnu-emacs@gnu.org; Wed, 22 Apr 2015 13:38:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 22 Apr 2015 17:38:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 20404 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 20404-submit@debbugs.gnu.org id=B20404.142972423827595 (code B ref 20404); Wed, 22 Apr 2015 17:38:02 +0000 Original-Received: (at 20404) by debbugs.gnu.org; 22 Apr 2015 17:37:18 +0000 Original-Received: from localhost ([127.0.0.1]:36742 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1YkyaM-0007B0-4T for submit@debbugs.gnu.org; Wed, 22 Apr 2015 13:37:18 -0400 Original-Received: from chene.dit.umontreal.ca ([132.204.246.20]:54291) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1YkyaJ-0007Ar-2s for 20404@debbugs.gnu.org; Wed, 22 Apr 2015 13:37:16 -0400 Original-Received: from pastel.home (lechon.iro.umontreal.ca [132.204.27.242]) by chene.dit.umontreal.ca (8.14.1/8.14.1) with ESMTP id t3MHbDqr014191; Wed, 22 Apr 2015 13:37:14 -0400 Original-Received: by pastel.home (Postfix, from userid 20848) id 9CF2633E7; Wed, 22 Apr 2015 13:37:13 -0400 (EDT) In-Reply-To: <20150422163110.68601.qmail@mail.muc.de> (Alan Mackenzie's message of "22 Apr 2015 16:31:10 -0000") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-NAI-Spam-Flag: NO X-NAI-Spam-Threshold: 5 X-NAI-Spam-Score: 0 X-NAI-Spam-Rules: 1 Rules triggered RV5284=0 X-NAI-Spam-Version: 2.3.0.9393 : core <5284> : inlines <2779> : streams <1426815> : uri <1913178> 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:101883 Archived-At: [ OFFTOPIC: the bug report is not about performance but about a functional bug in jit-lock-defer. ] > There's a solution (or, depending on your point of view, a workaround) > for this. You're using Emacs-25, so set fast-but-imprecise-scrolling to > t, or customize it (it's in customisation group "scrolling"). FWIW, on my machine, this doesn't make much difference: a single "font-lock one screen's worth" takes much too long, so after that one screen is displayed, Emacs takes a while catching up (with no display at all in the mean time). That's why after you installed your change, I installed the one I had suggested (which tweaks the decision about when to skip redisplay and when to defer font-lock and relies on using jit-lock-defer-time). In my tests, it worked significantly better (was able to keep up). So I recommend you try jit-lock-defer-time set to 0 instead of using fast-but-imprecise-scrolling, and see if you like the resulting behavior. IIUC if Emacs can *almost* keep up, then fast-but-imprecise-scrolling might be just enough to let it keep up, in which case the behavior may look be better than with jit-lock-defer-time (because the text is never displayed unfontified). But if the repeat rate is faster than that, then jit-lock-defer-time should give noticeably better results. Stefan