From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: Re: [RFC PATCH net-next 0/3] sctp: add GSO support Date: Thu, 28 Jan 2016 19:03:26 -0200 Message-ID: <20160128210326.GD6602@mrl.redhat.com> References: <063D6719AE5E284EB5DD2968C1650D6D1CCCEDE4@AcuExch.aculab.com> <9D5B8E18-A20A-4E27-8EB8-EE8856DFB184@lurchi.franken.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Laight , "netdev@vger.kernel.org" , Neil Horman , Vlad Yasevich , David Miller , "brouer@redhat.com" , "alexander.duyck@gmail.com" , "alexei.starovoitov@gmail.com" , "borkmann@iogearbox.net" , "marek@cloudflare.com" , "hannes@stressinduktion.org" , "fw@strlen.de" , "pabeni@redhat.com" , "john.r.fastabend@intel.com" , "linux-sctp@vger.kernel.org" To: Michael Tuexen Return-path: Received: from mx1.redhat.com ([209.132.183.28]:55843 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967646AbcA1VDd (ORCPT ); Thu, 28 Jan 2016 16:03:33 -0500 Content-Disposition: inline In-Reply-To: <9D5B8E18-A20A-4E27-8EB8-EE8856DFB184@lurchi.franken.de> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Jan 28, 2016 at 06:54:06PM +0100, Michael Tuexen wrote: > > On 28 Jan 2016, at 14:51, David Laight wrote: > > > > From: Marcelo Ricardo Leitner > >> Sent: 27 January 2016 17:07 > >> This patchset is merely a RFC for the moment. There are some > >> controversial points that I'd like to discuss before actually proposing > >> the patches. > > > > You also need to look at how a 'user' can actually get SCTP to > > merge data chunks in the first place. > > > > With Nagle disabled (and it probably has to be since the data flow > > is unlikely to be 'command-response' or 'unidirectional bulk') > > it is currently almost impossible to get more than one chunk > > into an ethernet frame. > > > > Support for MSG_MORE would help. > What about adding support for the explicit EOR mode as specified in > https://tools.ietf.org/html/rfc6458#section-8.1.26 Seizing the moment to clarify my understanding on that. :) Such multiple calls to send system calls will result in a single data chunk. Is that so? That's what I get from that text and also from this snippet: "Sending a message using sendmsg() is atomic unless explicit end of record (EOR) marking is enabled on the socket specified by sd (see Section 8.1.26)." Best regards, Marcelo > Best regards > Michael > > > > Given the current implementation you can get almost the required > > behaviour by turning nagle off and on repeatedly. > > > > I did wonder whether the queued data could actually be picked up > > be a Heartbeat chunk that is probing a different remote address > > (which would be bad news). > > > > David > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-sctp" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > >