Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263480AbTEDAju (ORCPT ); Sat, 3 May 2003 20:39:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263487AbTEDAju (ORCPT ); Sat, 3 May 2003 20:39:50 -0400 Received: from [81.68.134.96] ([81.68.134.96]:6917 "EHLO drinkel.cistron.nl") by vger.kernel.org with ESMTP id S263480AbTEDAjt (ORCPT ); Sat, 3 May 2003 20:39:49 -0400 Date: Sun, 4 May 2003 02:53:46 +0200 From: Miquel van Smoorenburg To: =?iso-8859-1?B?UOVs?= Halvorsen Cc: Mark Mielke , linux-kernel@vger.kernel.org, =?iso-8859-1?B?UOVs?= Halvorsen , miquels@cistron-office.nl Subject: Re: sendfile Message-ID: <20030504005346.GP32553@drinkel.cistron.nl> References: <20030430221834.GA23109@mark.mielke.cc> <20030501042831.GA26735@mark.mielke.cc> <3EB1A029.7080708@nortelnetworks.com> <20030502024147.GA523@mark.mielke.cc> <3EB1F1CD.4060702@nortelnetworks.com> <20030502210648.GA5322@mark.mielke.cc> Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset=ISO-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: ; from paalh@ifi.uio.no on Sat, May 03, 2003 at 23:01:21 +0200 X-Mailer: Balsa 2.0.10 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1574 Lines: 35 On Sat, 03 May 2003 23:01:21, P?l Halvorsen wrote: > > > Sat, May 03, 2003 at 12:42:59AM +0000, Miquel van Smoorenburg wrote: > > > In article <20030502210648.GA5322@mark.mielke.cc>, > > > Mark Mielke wrote: > > > >One question it raises in my mind, is whether there would be value > in > > > >improving write()/send() such that they detect that the userspace > > > >pointer refers entirely to mmap()'d file pages, and therefore no > copy > > > >of data from userspace -> kernelspace should be performed. > > > You mean like > > > > > > http://hypermail.idiosynkrasia.net/linux-kernel/archived/2003/week00/0056.html > > > > Yes, definately, and thank you for referring us to work that has > already > > been done. > > > > mark > > Does this mean that if you memory map a file and send it through TCP, > you'll have no copy operations transfering data from disk to NIC (except > the DMS transfers disk->memory and memory->NIC)? No. I just referred to an earlier discussion about this topic. That does't mean it has been implemented. In fact if you actually read that discussion you'll see that it probably won't be implemented at all. Mike. -- | Miquel van Smoorenburg | "I know one million ways, to always pick | | miquels@{drinkel.,}cistron.nl | the wrong fantasy" - the Black Crowes. | - 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/