From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: bug-reference-prog-mode slows down CC Mode's scrolling by ~7% Date: Sat, 11 Sep 2021 20:17:17 +0300 Message-ID: <837dfnghgi.fsf@gnu.org> References: <83a6kuyysv.fsf@gnu.org> <837dfwyird.fsf@gnu.org> <83tuj0ux6y.fsf@gnu.org> <83pmtouul2.fsf@gnu.org> <83k0jwus8w.fsf@gnu.org> <83k0jngtub.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="12889"; mail-complaints-to="usenet@ciao.gmane.io" Cc: acm@muc.de, emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sat Sep 11 19:18:29 2021 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 1mP6e5-000376-9m for ged-emacs-devel@m.gmane-mx.org; Sat, 11 Sep 2021 19:18:29 +0200 Original-Received: from localhost ([::1]:58482 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mP6e3-0005Oc-6u for ged-emacs-devel@m.gmane-mx.org; Sat, 11 Sep 2021 13:18:27 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:36958) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mP6d9-0004jG-SJ for emacs-devel@gnu.org; Sat, 11 Sep 2021 13:17:31 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:38200) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mP6d9-0000j7-6x; Sat, 11 Sep 2021 13:17:31 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:4943 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mP6d8-0004Of-Px; Sat, 11 Sep 2021 13:17:31 -0400 In-Reply-To: (message from Stefan Monnier on Sat, 11 Sep 2021 13:04:31 -0400) 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:274555 Archived-At: > From: Stefan Monnier > Cc: acm@muc.de, emacs-devel@gnu.org > Date: Sat, 11 Sep 2021 13:04:31 -0400 > > >> and it will probably say nil. > > That's sheer luck: it happens only when the invisible text between > > headings is longer than jit-lock-chunk-size. > > That was exactly the case I was talking about. > That's why I wrote a few messages ago: > > Maybe a good way to see the waste is to measure the time for the > initial font-lock in an outline-mode buffer where the screen is > filled with single-line headers and everything else is hidden: > a whole chunk will be fontified for each line, so with a single > 40-line screen you can expect to fontify 40 chunks (unless the > hidden text between lines is smaller than the chunk size, of > course). That's okay, but the thing is we do fontify invisible text, and 1500 characters could be easily 40 lines, so the probability of more than that to be hidden is not large, except in unusual cases like reading Lisp in Outline mode with all the code hidden.