From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: Default of jit-lock-stealth-time Date: Sat, 03 Mar 2007 14:36:28 +0100 Message-ID: <85irdi1mar.fsf@lola.goethe.zz> References: <85tzxazb8r.fsf@lola.goethe.zz> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1172929015 9646 80.91.229.12 (3 Mar 2007 13:36:55 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Sat, 3 Mar 2007 13:36:55 +0000 (UTC) Cc: rms@gnu.org, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Mar 03 14:36:48 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1HNUPn-00007Z-Fu for ged-emacs-devel@m.gmane.org; Sat, 03 Mar 2007 14:36:47 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HNUPn-00023j-1q for ged-emacs-devel@m.gmane.org; Sat, 03 Mar 2007 08:36:47 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1HNUPc-00023c-DB for emacs-devel@gnu.org; Sat, 03 Mar 2007 08:36:36 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1HNUPa-00023G-Fx for emacs-devel@gnu.org; Sat, 03 Mar 2007 08:36:35 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HNUPa-00023C-Aa for emacs-devel@gnu.org; Sat, 03 Mar 2007 08:36:34 -0500 Original-Received: from mail-in-05.arcor-online.net ([151.189.21.45]) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA:32) (Exim 4.52) id 1HNUPY-0000ux-0v; Sat, 03 Mar 2007 08:36:32 -0500 Original-Received: from mail-in-02-z2.arcor-online.net (mail-in-02-z2.arcor-online.net [151.189.8.14]) by mail-in-05.arcor-online.net (Postfix) with ESMTP id 994D418346F; Sat, 3 Mar 2007 14:36:30 +0100 (CET) Original-Received: from mail-in-08.arcor-online.net (mail-in-08.arcor-online.net [151.189.21.48]) by mail-in-02-z2.arcor-online.net (Postfix) with ESMTP id 82084113F5D; Sat, 3 Mar 2007 14:36:30 +0100 (CET) Original-Received: from lola.goethe.zz (dslb-084-061-027-182.pools.arcor-ip.net [84.61.27.182]) by mail-in-08.arcor-online.net (Postfix) with ESMTP id 5B8D72BAA28; Sat, 3 Mar 2007 14:36:30 +0100 (CET) Original-Received: by lola.goethe.zz (Postfix, from userid 1002) id 17AB11C460D3; Sat, 3 Mar 2007 14:36:28 +0100 (CET) In-Reply-To: (Eli Zaretskii's message of "Sat\, 03 Mar 2007 15\:22\:50 +0200") User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.94 (gnu/linux) X-detected-kernel: Linux 2.4-2.6 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:67255 Archived-At: Eli Zaretskii writes: > On a 3-GHz machine, with jit-lock-stealth-time set to nil, I measure a > consistent 5-10% increase in CPU time when paging up thru sufficiently > long Texinfo documents wrt to an already fontified buffer (18%-25% > percent the first time I page up, vs 10%-16% on subsequent attempts). > By contrast, with the default setting of jit-lock-stealth-time I see > only 1-3% of CPU being used while stealth fontification runs in the > background, which is barely distinguishable from a totally idle > machine. Well, I have a 1.2GHz laptop (but the results were similar for my previous 600MHz box). Apart from "pathological" buffers, paging through a file will deliver font locking fast enough to follow the user action, without causing the laptop to use the fan. In contrast, left alone to jit-lock-stealth-time=16, Emacs will eventually turn to eating 100% of CPU time (not 1-3%), causing the fan to go on and power drainage to occur. That does not mean that the problematic files will page through without noticeable delay when I go through them by hand: they tend to react sluggishly to editing. But that is a minor inconvenience compared to the computer going unresponsible at full CPU power frequently. I would consider stealth fontification completely useless as long as the computer can keep up with the user, which appears to be the case for your usage. In that case, investing the power when it is actually needed seems by far the sanest choice. -- David Kastrup, Kriemhildstr. 15, 44793 Bochum