Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 6 Mar 2003 12:42:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 6 Mar 2003 12:42:35 -0500 Received: from highland.isltd.insignia.com ([195.74.141.1]:54020 "EHLO highland.isltd.insignia.com") by vger.kernel.org with ESMTP id ; Thu, 6 Mar 2003 12:42:34 -0500 To: mingo@elte.hu (Ingo Molnar) Cc: Linus Torvalds , Jeff Garzik , Andrew Morton , , From: jvlists@ntlworld.com Subject: Re: [patch] "HT scheduler", sched-2.5.63-B3 Date: Thu, 06 Mar 2003 17:52:54 +0000 In-Reply-To: (mingo@elte.hu's message of "Thu, 6 Mar 2003 17:15:09 -0000") Message-ID: User-Agent: Gnus/5.090013 (Oort Gnus v0.13) XEmacs/21.4 (Military Intelligence (RC1), i686-pc-linux) References:

MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2030 Lines: 45 mingo@elte.hu (Ingo Molnar) writes: > X is special. Especially in Andrew's wild-window-dragging experiment X is > a pure CPU-bound task that just eats CPU cycles no end. There _only_ thing > that makes it special is that there's a human looking at the output of the > X client. This is information that is simply not available to the kernel. Isn't it special because the window manager and other interactive tasks are blocked waiting for it? Presumably during a wild-window drag there will be loads of block-wakeup sequences between X and the window manager. IF every such event gave a little boost to the X server that would mean the X server would get loads of interactivity brownie points. This may be a stupid idea (feel free to ignore, it may even be what the kernel already does), but if you had a separate input server and display server instead of one X server you could follow the trail all the way from the real user. /dev/input/mice is special because we know it interfaces to the user. The X input server gains points for waiting on /dev/input/mice interactive X program gains points for waiting on X input server X output server is special because it blocks waiting on the interactive X program (and vice versa!) The hard part would be detecting interactivity for stuff waiting on ip sockets. If this information was available to user programs then the X display server could even prioritize rendering a new character in bash over displaying the fishbowl animation running in the background. Jan P.S. IMVHO the xine problem is completely different as has nothing to with interactivity but with the fact that it is soft real-time. i.e. you need to distingish xine from say a gimp filter or a 3D renderer with incremental live updates of the scene it is creating. - 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/