From owner-freebsd-current Sun Dec 2 11:14:54 2001 Delivered-To: freebsd-current@freebsd.org Received: from mass.dis.org (mass.dis.org [216.240.45.41]) by hub.freebsd.org (Postfix) with ESMTP id 09C2137B405 for ; Sun, 2 Dec 2001 11:14:46 -0800 (PST) Received: from mass.dis.org (localhost [127.0.0.1]) by mass.dis.org (8.11.6/8.11.3) with ESMTP id fB2JJ7W01626; Sun, 2 Dec 2001 11:19:08 -0800 (PST) (envelope-from msmith@mass.dis.org) Message-Id: <200112021919.fB2JJ7W01626@mass.dis.org> X-Mailer: exmh version 2.1.1 10/15/1999 To: culverk@wam.umd.edu Cc: Alan Eldridge , freebsd-current@freebsd.org Subject: Re: parallel port i/o hogs cpu badly; is this normal? In-reply-to: Your message of "Sun, 02 Dec 2001 14:10:58 EST." <20011202191049.28EF137B417@hub.freebsd.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sun, 02 Dec 2001 11:19:07 -0800 From: Mike Smith Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG > I don't know if there's a way to stop this, but it's normal, whenever I use > my Parallel port zip drive, I have similar problems. There isn't, really. The parallel port is terribly inefficient. > > But what surprises me is that copying that data to the parallel intfc burns > > up an incredible amount of CPU. Until the document is printed, there's a > > steady bg buzz of ~10% CPU use, with periods of 50% and even 100% CPU > > utilization by the 'parallel'[1] process. The load is sufficient that it > > locks out the mouse on X (interrupt blocking?). > > > > Anyone care to comment? Does this sound normal? Is there a way to reduce > > the amount of CPU needed to drive the parallel port? Get a USB printer, or a USB-parallel adapter cable. It won't necessarily be much faster, but it will use a lot less CPU. The cables are pretty cheap (< $30), and they're mostly based on a single design that's known to work. -- ... every activity meets with opposition, everyone who acts has his rivals and unfortunately opponents also. But not because people want to be opponents, rather because the tasks and relationships force people to take different points of view. [Dr. Fritz Todt] V I C T O R Y N O T V E N G E A N C E To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message