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: cc-mode fontification feels random Date: Fri, 11 Jun 2021 20:53:10 +0300 Message-ID: <83k0n09tkp.fsf@gnu.org> References: <62e438b5-d27f-1d3c-69c6-11fe29a76d74@dancol.org> <83fsxsdxhu.fsf@gnu.org> <83pmwudgw3.fsf@gnu.org> <83k0n2cjg5.fsf@gnu.org> <83im2lbqmv.fsf@gnu.org> <179f6e4fa40.2816.cc5b3318d7e9908e2c46732289705cb0@dancol.org> <83fsxpbpn9.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="34262"; mail-complaints-to="usenet@ciao.gmane.io" Cc: rudalics@gmx.at, dancol@dancol.org, emacs-devel@gnu.org, monnier@iro.umontreal.ca, rms@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Jun 11 19:54:11 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 1lrlM9-0008ia-Q8 for ged-emacs-devel@m.gmane-mx.org; Fri, 11 Jun 2021 19:54:09 +0200 Original-Received: from localhost ([::1]:60684 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lrlM8-0004kT-TM for ged-emacs-devel@m.gmane-mx.org; Fri, 11 Jun 2021 13:54:08 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:44514) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lrlLX-000436-Vm for emacs-devel@gnu.org; Fri, 11 Jun 2021 13:53:31 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:36418) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lrlLT-0008Mb-Ow; Fri, 11 Jun 2021 13:53:28 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:3443 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 1lrlLN-0005L8-KG; Fri, 11 Jun 2021 13:53:21 -0400 In-Reply-To: (message from Alan Mackenzie on Fri, 11 Jun 2021 16:11:19 +0000) 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:270708 Archived-At: > Date: Fri, 11 Jun 2021 16:11:19 +0000 > Cc: Daniel Colascione , rudalics@gmx.at, > monnier@iro.umontreal.ca, rms@gnu.org, emacs-devel@gnu.org > From: Alan Mackenzie > > I have measured CC Mode's scrolling performance using: > > (defmacro time-it (&rest forms) > "Time the running of a sequence of forms using `float-time'. > Call like this: \"M-: (time-it (foo ...) (bar ...) ...)\"." > `(let ((start (float-time))) > ,@forms > (- (float-time) start))) > > together with > > M-: (time-it (scroll-up-window) (sit-for 0)) > > on regions of text which are not yet fontified. My window has 65 lines > of buffer text. Starting at the middle of xdisp.c, I see the following > timings for the first few scrolls: > > 0.026s, 0.025s, 0.026s, 0.078s, 0.026s, 0.027s. > > That is, with the exception of the fourth timing, the scroll operation > takes a little over 1/40 second. > > This is in an Emacs-28 compiled with default optimisation, on a 4 > year-old first generation Ryzen machine. > > For me personally, this scrolling speed, in conjunction with > fast-but-imprecise-scrolling, is acceptable. I also accept there are > people with slower machines. I suggest to compare these times with Emacs 23 to see how we regressed.