From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 4 Sep 2001 15:35:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 4 Sep 2001 15:35:20 -0400 Received: from h157s242a129n47.user.nortelnetworks.com ([47.129.242.157]:36560 "EHLO zcars0m9.ca.nortel.com") by vger.kernel.org with ESMTP id ; Tue, 4 Sep 2001 15:35:07 -0400 Message-ID: <3B952CFE.A3B6FF95@nortelnetworks.com> Date: Tue, 04 Sep 2001 15:35:26 -0400 X-Sybari-Space: 00000000 00000000 00000000 From: "Christopher Friesen" X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.3-custom i686) X-Accept-Language: en MIME-Version: 1.0 To: Roger Larsson Cc: Fred , linux-kernel@vger.kernel.org Subject: Re: Should I use Linux to develop driver for specialized ISA card? In-Reply-To: <01090410264000.14864@bits.linuxball> <3B950034.17909E5D@nortelnetworks.com> <200109041823.f84INqE13918@maild.telia.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Orig: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Roger Larsson wrote: > > On Tuesday den 4 September 2001 18:24, Christopher Friesen wrote: > > Fred wrote: > > > I'm curious, Alan, Why? I'm a hardware developer, and I would have > > > assumed that linux would have been ideal for real time / embedded > > > projects? (routers / controllers / etc.) Is there, for instance, a reason > > > to suspect that linux would not be able to respond to interrupts at say > > > 8Khz? > > > of course I know nothing of rtlinux so I'll read. > > > > I'm involved in a project where we are using linux in an embedded > > application. We've got a gig of ram, no hard drives, no video, and the only > > I/O is serial, ethernet and fiberchannel. > > > > We have a realtime process that tries to run every 50ms. We're seeing > > actual worst-case scheduling latencies upwards of 300-400ms. > 1) Why shouldn't the low-latency patches work for another architecture? > Andrew Morton might be interested to fix other architectures too. > (but most patches are not in architecture specific code) Well, a while back I took a look at the low latency patch and saw a bunch of arch-specific files being modified so I assumed that it wouldn't do much on a different architecture. I may have been wrong. I guess its time for me to do some testing. Chris -- Chris Friesen | MailStop: 043/33/F10 Nortel Networks | work: (613) 765-0557 3500 Carling Avenue | fax: (613) 765-2986 Nepean, ON K2H 8E9 Canada | email: cfriesen@nortelnetworks.com