From owner-freebsd-questions Thu Feb 5 01:20:51 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id BAA18085 for questions-outgoing; Thu, 5 Feb 1998 01:20:51 -0800 (PST) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from septimius.mbfys.kun.nl (septimius.mbfys.kun.nl [131.174.173.155]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id BAA18052 for ; Thu, 5 Feb 1998 01:20:45 -0800 (PST) (envelope-from thom@mbfys.kun.nl) Received: from antonius.mbfys.kun.nl by septimius.mbfys.kun.nl via antonius.mbfys.kun.nl [131.174.173.161] with ESMTP id KAA19335 (8.6.10/2.4); Thu, 5 Feb 1998 10:20:44 +0100 From: Thom Oostendorp Received: by antonius.mbfys.kun.nl id KAA00216 (8.8.3/2.1); Thu, 5 Feb 1998 10:21:54 +0100 Message-Id: <199802050921.KAA00216@antonius.mbfys.kun.nl> Subject: Re: modem - X problem To: dwhite@resnet.uoregon.edu Date: Thu, 5 Feb 1998 10:21:53 +0100 (MET) Cc: freebsd-questions@FreeBSD.ORG In-Reply-To: from "Doug White" at Feb 4, 98 12:26:23 pm X-Mailer: ELM [version 2.4 PL25] MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG X-To-Unsubscribe: mail to majordomo@FreeBSD.org "unsubscribe questions" Hello Doug White. You wrote: > > On Wed, 4 Feb 1998, Thom Oostendorp wrote: > > > I seem to have a weird problem when using a modem connection and X11 > > simultaniously. > > > > Whenever I start a connection on my modem (it's on sio1) while X is running > > X starts slurping up 50% of CPU time,and the system slows down > > considerably. This happens for instance as soon as I start seyon, or > > when ppp starts making an automatic connection. > > As soon as seyon, ppp, or whatever stops using the modem, X drops > > back to a modest few % of CPU time. > > You don't have the modem and mouse set to the same port, do you? > No, I'm not that stupid. The mouse is on sio0. After some experimenting, if find that the combination of running X11 and 'cat /dev/ttyd1' is enough to cause the problem. 'top' shows that some 20% of run time is spent on interupts, and some 40% by X11. 'cat /dev/ttyd1' without X11 generates no interupts, and neither does X11 without 'cat /dev/ttyd1'. Clearly, the interupts are the source of the slowness of the system. Where they come from is a mistery to me; there is no data being recieved at that time. I start suspecting a hardware problem, like some cross talk between the com1 and com2 ports. However, in that case one would expect the same problems in Windows. Thom -- Thom Oostendorp Dept. of Medical Physics and Biophysics thom@mbfys.kun.nl Geert Grooteplein 21 6525 EZ Nijmegen http://www.mbfys.kun.nl/~thom University of Nijmegen, the Netherlands voice: +31 24 3614240 fax: +31 24 3541435 buzzer: 06 65 325 533 (Netherlands only)