Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756937AbXHTAtj (ORCPT ); Sun, 19 Aug 2007 20:49:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751365AbXHTAt2 (ORCPT ); Sun, 19 Aug 2007 20:49:28 -0400 Received: from stargate.chelsio.com ([12.22.49.110]:28013 "EHLO stargate.chelsio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751915AbXHTAt1 convert rfc822-to-8bit (ORCPT ); Sun, 19 Aug 2007 20:49:27 -0400 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [ofa-general] Re: [PATCH RFC] RDMA/CMA: Allocate PS_TCPportsfrom the host TCP port space. Date: Sun, 19 Aug 2007 17:47:59 -0700 Message-ID: <8A71B368A89016469F72CD08050AD334018E20BE@maui.asicdesigners.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [ofa-general] Re: [PATCH RFC] RDMA/CMA: Allocate PS_TCPportsfrom the host TCP port space. thread-index: AcfiwoBrETjN8S2jTlSvLdmE96hfCQAABCGQ References: <8A71B368A89016469F72CD08050AD334018E209C@maui.asicdesigners.com><20070819.160428.76330262.davem@davemloft.net><8A71B368A89016469F72CD08050AD334018E20BC@maui.asicdesigners.com> <20070819.174017.77241227.davem@davemloft.net> From: "Felix Marti" To: "David Miller" Cc: , , , , , Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1595 Lines: 36 > -----Original Message----- > From: David Miller [mailto:davem@davemloft.net] > Sent: Sunday, August 19, 2007 5:40 PM > To: Felix Marti > Cc: sean.hefty@intel.com; netdev@vger.kernel.org; rdreier@cisco.com; > general@lists.openfabrics.org; linux-kernel@vger.kernel.org; > jeff@garzik.org > Subject: Re: [ofa-general] Re: [PATCH RFC] RDMA/CMA: Allocate > PS_TCPportsfrom the host TCP port space. > > From: "Felix Marti" > Date: Sun, 19 Aug 2007 17:32:39 -0700 > > [ Why do you put that "[Felix Marti]" everywhere you say something? > It's annoying and superfluous. The quoting done by your mail client > makes clear who is saying what. ] > > > Hmmm, interesting... I guess it is impossible to even have > > a discussion on the subject. > > Nice try, Herbert Xu gave a great explanation. [Felix Marti] David and Herbert, so you agree that the user<>kernel space memory copy overhead is a significant overhead and we want to enable zero-copy in both the receive and transmit path? - Yes, copy avoidance is mainly an API issue and unfortunately the so widely used (synchronous) sockets API doesn't make copy avoidance easy, which is one area where protocol offload can help. Yes, some apps can resort to sendfile() but there are many apps which seem to have trouble switching to that API... and what about the receive path? - 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/