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: [PATCH] Re: cc-mode fontification feels random Date: Tue, 31 Aug 2021 16:23:08 +0300 Message-ID: <83v93lsq83.fsf@gnu.org> References: <835yvmka50.fsf@gnu.org> <9377d9ec-a3e5-ceea-8a9a-523a420f13f7@dancol.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="14618"; mail-complaints-to="usenet@ciao.gmane.io" Cc: dancol@dancol.org, monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Tue Aug 31 15:38:11 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 1mL3xr-0003YG-72 for ged-emacs-devel@m.gmane-mx.org; Tue, 31 Aug 2021 15:38:11 +0200 Original-Received: from localhost ([::1]:50658 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mL3xq-0001AL-1m for ged-emacs-devel@m.gmane-mx.org; Tue, 31 Aug 2021 09:38:10 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:48366) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mL3jU-00084n-Gl for emacs-devel@gnu.org; Tue, 31 Aug 2021 09:23:22 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:35348) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mL3jS-0000ch-CK; Tue, 31 Aug 2021 09:23:18 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:4167 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 1mL3jR-0007IV-Sz; Tue, 31 Aug 2021 09:23:18 -0400 In-Reply-To: (message from Alan Mackenzie on Tue, 31 Aug 2021 10:54:23 +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:273585 Archived-At: > Date: Tue, 31 Aug 2021 10:54:23 +0000 > Cc: Daniel Colascione , Eli Zaretskii , > emacs-devel@gnu.org > From: Alan Mackenzie > > For my current project (finding CC Mode "found types") stealth > fontification is not ideal - what I need is a single pass through the > whole buffer to detect the types, and that should be as fast as > possible. The current stealth fontification is not fast (it doesn't > need to be) and carries on working until Emacs is shut down. The purpose of jit-lock-stealth is different, that's why. > So, it seems I want something like stealth, but not quite. Yes, you want a different feature. > How about, say jit-lock-single-fontification - it would apply to > individual buffers only, would scan through the buffer precisely > once, and would do just enough 500-byte chunks at at time to take > 0.05 seconds (configurable). > > On my machine in C Mode, approximately 100 chunks are fontified per > second. So if we had jit-lock-single-nice at 0.1 seconds, the time > taken to scan xdisp.c would be approximately 1 to 1.5 minutes. On a > smaller file, say syntax.c (a tenth of the size) it would take 5 - 10 > seconds. This is barely worse than context fontification, and would > only happen at mode start up. What happens if you unleash this jit-lock-single-fontification, and then type at a relatively slow pace: does Emacs still feel responsive enough? And how much of CPU does it use in that case?