Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264443AbUDSNi4 (ORCPT ); Mon, 19 Apr 2004 09:38:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264421AbUDSNhf (ORCPT ); Mon, 19 Apr 2004 09:37:35 -0400 Received: from hermine.idb.hist.no ([158.38.50.15]:60169 "HELO hermine.idb.hist.no") by vger.kernel.org with SMTP id S264433AbUDSNb4 (ORCPT ); Mon, 19 Apr 2004 09:31:56 -0400 Message-ID: <4083D511.6040702@aitel.hist.no> Date: Mon, 19 Apr 2004 15:33:05 +0200 From: Helge Hafting Organization: AITeL, HiST User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20031107 Debian/1.5-3 X-Accept-Language: no, en MIME-Version: 1.0 To: Antti Lankila CC: linux-kernel@vger.kernel.org Subject: Re: elevator=as, or actually gpm doesn't get time from scheduler??? References: In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2226 Lines: 47 Antti Lankila wrote: > In response to Nick Piggin's: > > >>The only other problems I can think of that you might be >>having are chipset problems, or CPU scheduler problems. >>Which reminds me, do you have your X server at nice 0? > > > X has been reniced to zero. But hey! I was doing "cat /dev/psaux" when mouse > stopped moving in X, and I _did_ see data coming from /dev/psaux! So this is > a major update to my understanding of the problem. > > But make no mistake, I have been doing this cat /dev/psaux test earlier and > at that time I did _not_ see chars coming out of psaux when the mouse > stopped. That is why I thought I had established that the problem is in the > kernel. I must retest this on the other machines involved when I get to > their consoles next week. I can not explain why this time psaux appears to > work regardless of the userland mouse stall, so for now I must assume some > other factor confused the cat /dev/psaux test at that time. > > My X reads gpmdata, so perhaps that's the problem? I now undercut gpm in > order to examine the situation, and my system behaves _perfectly_ as far as > I can see. The mouse issues are all gone. (gpm is still running in the > background, X just reads psaux directly. As I have understood, this is > possible in 2.6 while in 2.4 it caused a problem for multiple readers.) > Gpm might be a problem in high-load situations, for two reasons: 1. gpm is another process. The mouse moves, it takes some time before gpm gets to read it because the cpu is busy. Then it pass stuff onto the fifo that X reads from, but now X waits for a while because so much is going on. 2. You may play with the priority of x in order to get better response, but this does not affect the priority of gpm. With X reading psaux directly, you avoid some waiting. And X may get a priority boost for waiting for the mouse to move. With gpm this bonus goes to gpm which may have a lot less to do with it. Helge Hafting - 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/