From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 22 Aug 2001 17:15:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 22 Aug 2001 17:14:54 -0400 Received: from pizda.ninka.net ([216.101.162.242]:23680 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id ; Wed, 22 Aug 2001 17:14:44 -0400 Date: Wed, 22 Aug 2001 14:14:48 -0700 (PDT) Message-Id: <20010822.141448.112623586.davem@redhat.com> To: groudier@free.fr Cc: gibbs@scsiguy.com, axboe@suse.de, skraw@ithnet.com, phillips@bonn-fries.net, linux-kernel@vger.kernel.org Subject: Re: With Daniel Phillips Patch From: "David S. Miller" In-Reply-To: <20010822223658.X932-100000@gerard> In-Reply-To: <20010822.114620.77339267.davem@redhat.com> <20010822223658.X932-100000@gerard> X-Mailer: Mew version 2.0 on Emacs 21.0 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=big5 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by leeloo.zip.com.au id HAA03046 From: Grard Roudier Date: Wed, 22 Aug 2001 23:07:47 +0200 (CEST) And I seem to understand that David's preferred SUN hardware only allows streaming when using SAC with IOMMU.:-) It is true. And using DAC is 1 PCI cycle lost per transaction and if we are picky on performances ... True. This is why I find it mysterious when I run across a device which does not issue SAC for addresses with only 32-bits of significance. Happily, most do behave this way. Later, David S. Miller davem@redhat.com :.˛mkabzwmb˛mbz_^nrzh&zzޗ++zfh~iz_j:+v)ߣmSy杶ii