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, 9 Jan 2001 05:33:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 9 Jan 2001 05:33:05 -0500 Received: from ns.caldera.de ([212.34.180.1]:36103 "EHLO ns.caldera.de") by vger.kernel.org with ESMTP id ; Tue, 9 Jan 2001 05:32:51 -0500 Date: Tue, 9 Jan 2001 11:31:45 +0100 From: Christoph Hellwig To: Ingo Molnar Cc: Rik van Riel , "David S. Miller" , netdev@oss.sgi.com, linux-kernel@vger.kernel.org Subject: Re: [PLEASE-TESTME] Zerocopy networking patch, 2.4.0-1 Message-ID: <20010109113145.A28758@caldera.de> Mail-Followup-To: Ingo Molnar , Rik van Riel , "David S. Miller" , netdev@oss.sgi.com, linux-kernel@vger.kernel.org In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: ; from mingo@elte.hu on Tue, Jan 09, 2001 at 11:23:41AM +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 09, 2001 at 11:23:41AM +0100, Ingo Molnar wrote: > > On Mon, 8 Jan 2001, Rik van Riel wrote: > > > I really think the zerocopy network stuff should be ported to kiobuf > > proper. > > yep, we talked to Stephen Tweedie about this already, but it involves some > changes in kiovec support and we didnt want to touch too much code for > 2.4. In any case, the zerocopy code is 'kiovec in spirit' (uses vectors of > struct page *, offset, size entities), Yep. That is why I was so worried aboit the writepages file op. It's rather hackish (only write, looks usefull only for networking) instead of the proposed rw_kiovec fop. > > > The usefulness of the patch you posted is rather .. umm .. limited. > > [...] > > i violently disagree :-) The upcoming TUX release is based on David's and > Alexey's cleaned-up zerocopy framework. [thus TUX and zerocopy are > separated.] David's patch adds a *very* scalable implementation of > zerocopy sendfile() and zerocopy sendmsg(), the panacea of fileserver > (webserver) scalability - it can be used by Apache, Samba and other > fileservers. The new zerocopy networking code DMA-s straight out of the > pagecache, natively supports hardware-checksumming and highmem (64-bit DMA > on 32-bit systems) zerocopy as well and multi-fragment DMA - no > limitations. We can saturate a gigabit link with TCP traffic, at about 20% > CPU usage on a 500 MHz x86 UP system. David and Alexey's patch is cool - > check it out! Yuck. A new file_opo just to get a few benchmarks right ... I hope the writepages stuff will not be merged in Linus tree (but I wish the code behind it!) Christoph -- Whip me. Beat me. Make me maintain AIX. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/