Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261409AbVEYIfp (ORCPT ); Wed, 25 May 2005 04:35:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261486AbVEYIfp (ORCPT ); Wed, 25 May 2005 04:35:45 -0400 Received: from main.gmane.org ([80.91.229.2]:8678 "EHLO ciao.gmane.org") by vger.kernel.org with ESMTP id S261409AbVEYIfh (ORCPT ); Wed, 25 May 2005 04:35:37 -0400 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Giuseppe Bilotta Subject: Re: RT patch acceptance Date: Wed, 25 May 2005 10:29:43 +0200 Message-ID: <1sqzfpcvfd64k.19ompsenhoq7d.dlg@40tude.net> References: <1116957953.31174.37.camel@dhcp153.mvista.com> <20050524224157.GA17781@nietzsche.lynx.com> <1116978244.19926.41.camel@dhcp153.mvista.com> <20050525001019.GA18048@nietzsche.lynx.com> <1116981913.19926.58.camel@dhcp153.mvista.com> <20050525005942.GA24893@nietzsche.lynx.com> <1116982977.19926.63.camel@dhcp153.mvista.com> <20050524184351.47d1a147.akpm@osdl.org> <4293DCB1.8030904@mvista.com> <20050524192029.2ef75b89.akpm@osdl.org> <20050525063306.GC5164@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@sea.gmane.org X-Gmane-NNTP-Posting-Host: oblomov.dipmat.unict.it User-Agent: 40tude_Dialog/2.0.15.1 Posted-And-Mailed: yes Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1858 Lines: 35 On Wed, 25 May 2005 08:33:06 +0200, Ingo Molnar wrote: > i agree in theory, but interestingly, people who use the -RT branch do > report a smoother desktop experience. While it might also be a > psychological effect, under -RT an interactive X process has the same > kind of latency properties as if all of the mouse pointer input and > rendering was done in the kernel (like some other desktop OSs do). The only way to actually know if it really makes a difference or not would be to run a double-blind test, with people not knowing if they're running a RT kernel or not, and then reporting their experience re. desktop smoothness. But I doubt such a test could actually be taken into consideration, unless distributions start shipping with different kernels without the user knowing, and then ask about how it feels ... This all being said, esp. concerning the next point you rise > so in terms of mouse pointer 'smoothness', it might very well be > possible for humans to detect a couple of msec delays visually - even > though they are unable to notice those delays directly. (Isnt there some > existing research on this?) IIRC, there have been (I'm not sure if there still are) some issues with IRQs being lost on the input devices, missing keys, missing events or misbehaving of mice and similar ... would these problems (and the underlying issues in the codepaths) be more easy or harder to happen and to trace if they happened? -- Giuseppe "Oblomov" Bilotta "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." Benjamin Franklin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/