From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.bugs Subject: bug#33670: 26.1; very large c++-mode yank performance regression 25.3_1-x86_64 -> 26.1-x86_64 Date: Sun, 9 Dec 2018 12:01:02 +0000 Message-ID: <20181209120102.GB4878@ACM> References: <20181208204036.61878.qmail@mail.muc.de> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1544357114 29115 195.159.176.226 (9 Dec 2018 12:05:14 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 9 Dec 2018 12:05:14 +0000 (UTC) User-Agent: Mutt/1.10.1 (2018-07-13) Cc: 33670@debbugs.gnu.org To: Chris Hecker Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Sun Dec 09 13:05:09 2018 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1gVxpd-0007S6-5o for geb-bug-gnu-emacs@m.gmane.org; Sun, 09 Dec 2018 13:05:09 +0100 Original-Received: from localhost ([::1]:55075 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gVxrj-00048U-HF for geb-bug-gnu-emacs@m.gmane.org; Sun, 09 Dec 2018 07:07:19 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:57541) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gVxrY-00047p-1N for bug-gnu-emacs@gnu.org; Sun, 09 Dec 2018 07:07:08 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gVxrT-0004yF-3Z for bug-gnu-emacs@gnu.org; Sun, 09 Dec 2018 07:07:07 -0500 Original-Received: from debbugs.gnu.org ([208.118.235.43]:35012) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gVxrS-0004y9-UX for bug-gnu-emacs@gnu.org; Sun, 09 Dec 2018 07:07:02 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1gVxrS-0002sv-PN for bug-gnu-emacs@gnu.org; Sun, 09 Dec 2018 07:07:02 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Alan Mackenzie Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Sun, 09 Dec 2018 12:07:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 33670 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 33670-submit@debbugs.gnu.org id=B33670.154435717211002 (code B ref 33670); Sun, 09 Dec 2018 12:07:02 +0000 Original-Received: (at 33670) by debbugs.gnu.org; 9 Dec 2018 12:06:12 +0000 Original-Received: from localhost ([127.0.0.1]:39265 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gVxqd-0002rO-Pd for submit@debbugs.gnu.org; Sun, 09 Dec 2018 07:06:12 -0500 Original-Received: from colin.muc.de ([193.149.48.1]:55444 helo=mail.muc.de) by debbugs.gnu.org with smtp (Exim 4.84_2) (envelope-from ) id 1gVxqc-0002rG-C6 for 33670@debbugs.gnu.org; Sun, 09 Dec 2018 07:06:10 -0500 Original-Received: (qmail 77617 invoked by uid 3782); 9 Dec 2018 12:06:09 -0000 Original-Received: from acm.muc.de (p2E5D55DE.dip0.t-ipconnect.de [46.93.85.222]) by colin.muc.de (tmda-ofmipd) with ESMTP; Sun, 09 Dec 2018 13:06:08 +0100 Original-Received: (qmail 5293 invoked by uid 1000); 9 Dec 2018 12:01:02 -0000 Content-Disposition: inline In-Reply-To: X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 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" Xref: news.gmane.org gmane.emacs.bugs:153253 Archived-At: Hello, Chris. On Sat, Dec 08, 2018 at 13:31:42 -0800, Chris Hecker wrote: > It wasn’t a string, it was a single line function call. Very simple code. > Like: > Foo(); Ah. That's worrying. The cause of the slowdown will not be found in that single line of code, rather in its context. The way CC Mode works is, at each buffer change, a region around the change where side effects might propagate is calculated. This region is then checked for any such side effects. I'm guessing here, but it might well be that the region in this case has been extended far more than is necessary. Is there any way you could get a copy of the file to me, specifying a line which shows the problem? It's practically impossible to debug otherwise. Thanks! > Chris -- Alan Mackenzie (Nuremberg, Germany).