Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 28 Aug 2002 09:50:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 28 Aug 2002 09:50:54 -0400 Received: from hq.fsmlabs.com ([209.155.42.197]:1966 "EHLO hq.fsmlabs.com") by vger.kernel.org with ESMTP id ; Wed, 28 Aug 2002 09:50:54 -0400 Date: Wed, 28 Aug 2002 07:53:19 -0600 From: yodaiken@fsmlabs.com To: "Richard B. Johnson" Cc: yodaiken@fsmlabs.com, Mark Hounschell , "Wessler, Siegfried" , "'linux-kernel@vger.kernel.org'" Subject: Re: interrupt latency Message-ID: <20020828075319.A24146@hq.fsmlabs.com> References: <20020827145631.B877@hq.fsmlabs.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from root@chaos.analogic.com on Wed, Aug 28, 2002 at 08:18:25AM -0400 Organization: FSM Labs Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 811 Lines: 21 On Wed, Aug 28, 2002 at 08:18:25AM -0400, Richard B. Johnson wrote: > No, no, no. There is no such port read that takes 18 microseconds, even > on old '386 machines with real ISR slots. A port read on those took > almost exactly 300 nanoseconds and, in fact, was the limiting factor > for the programmed I/O devices on the ISA bus. Amazing how they can do that with a bus clock that is much slower -) -- --------------------------------------------------------- Victor Yodaiken Finite State Machine Labs: The RTLinux Company. www.fsmlabs.com www.rtlinux.com - 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/