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, 12 Mar 2002 04:00:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 12 Mar 2002 03:59:55 -0500 Received: from 99dyn73.com21.casema.net ([62.234.30.73]:51666 "EHLO abraracourcix.bitwizard.nl") by vger.kernel.org with ESMTP id ; Tue, 12 Mar 2002 03:59:39 -0500 Message-Id: <200203120859.JAA04099@cave.bitwizard.nl> Subject: zero copy. To: Linux kernel mailing list Date: Tue, 12 Mar 2002 09:59:36 +0100 (MET) CC: linux-net@vger.kernel.org From: R.E.Wolff@BitWizard.nl (Rogier Wolff) X-notice1: This Email contains my Email address. This grants you the right X-notice2: to communicate with me using this address, related to the subject X-notice3: in this message. Unsollicitated mass-mailings are explictly X-notice4: forbidden here, and by Dutch law. X-Mailer: ELM [version 2.4ME+ PL60 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, Is linux able to do zero copy? I remember from previous discussions that there was always a camp that would claim that the copy was free because of the checksum, and/or the other way around. And warming the cache on input would prove to eliminate almost all overhead. I have an application where the bulk of the data is NOT generated or consumed by the CPU, in fact, the CPU does not have enough bandwidth to move all the data. We really need to have the DMA-devices go and get the data for themselves.... So far, I'm finding more or less unavoidable copy to/from user calls in both the tcp send and the tcp recieve path..... Suggestions? Roger. -- ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 ** *-- BitWizard writes Linux device drivers for any device you may have! --* * There are old pilots, and there are bold pilots. * There are also old, bald pilots.