From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: The current state of the comment-cache branch Date: Wed, 28 Dec 2016 12:10:31 -0500 Message-ID: References: <20161223215056.GA2771@acm.fritz.box> <83fuldzre1.fsf@gnu.org> <20161224083054.GA2212@acm.fritz.box> <83bmw1zoy8.fsf@gnu.org> <20161224094246.GD2212@acm.fritz.box> <8360m9zf4h.fsf@gnu.org> <20161228083738.GA2304@acm.fritz.box> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1482945116 30199 195.159.176.226 (28 Dec 2016 17:11:56 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 28 Dec 2016 17:11:56 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1.50 (gnu/linux) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Dec 28 18:11:53 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cMHlW-00077e-Q0 for ged-emacs-devel@m.gmane.org; Wed, 28 Dec 2016 18:11:50 +0100 Original-Received: from localhost ([::1]:60204 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cMHlb-0007DQ-Ng for ged-emacs-devel@m.gmane.org; Wed, 28 Dec 2016 12:11:55 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:54934) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cMHkW-0006Li-FF for emacs-devel@gnu.org; Wed, 28 Dec 2016 12:10:49 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cMHkT-0002i8-Ao for emacs-devel@gnu.org; Wed, 28 Dec 2016 12:10:48 -0500 Original-Received: from [195.159.176.226] (port=39672 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cMHkT-0002hW-3j for emacs-devel@gnu.org; Wed, 28 Dec 2016 12:10:45 -0500 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1cMHkL-0006iT-1m for emacs-devel@gnu.org; Wed, 28 Dec 2016 18:10:37 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 17 Original-X-Complaints-To: usenet@blaine.gmane.org Cancel-Lock: sha1:fcDWV5bLomd4wjGOkfZCrkRcNPA= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 195.159.176.226 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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" Xref: news.gmane.org gmane.emacs.devel:210906 Archived-At: >> Also in the latest case where a major slow down showed up in CC-mode, >> the problem was reversed: CC-mode had some special code for when >> open-paren-in-column-0-is-defun-start is non-nil (can't remember what >> it was for), which was the cause of the slow down, IIRC. > Bug #22884. This isn't quite accurate. The slowdown happened when C > Mode thought that the "(" in the comment was a BOD and in repeated > scanning to point (which is typically harmless) was scanning many times > over ~40k characters. The thing I don't understand in this explanation is that if open-paren-in-column-0-is-defun-start is set to nil the problem did not show up, yet setting it to nil means that the scanning was done over *more* than 40K characters so it should have made the problem worse. Stefan