From owner-freebsd-net@FreeBSD.ORG Wed May 23 05:57:50 2012 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 8B091106566C; Wed, 23 May 2012 05:57:50 +0000 (UTC) (envelope-from venkatduvvuru.ml@gmail.com) Received: from mail-ob0-f182.google.com (mail-ob0-f182.google.com [209.85.214.182]) by mx1.freebsd.org (Postfix) with ESMTP id 2D9D38FC15; Wed, 23 May 2012 05:57:50 +0000 (UTC) Received: by obcni5 with SMTP id ni5so14358465obc.13 for ; Tue, 22 May 2012 22:57:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=3Vk8ZOzZYXfiaWM7DwhI8itkfymPMc4oZNOSSYdlIHo=; b=mfV3mHFSvzvUW2eg1Lywd22b4ipydhHQheWCo740XczbJI6q/1oQA3Dwq2RM/eOhPv 1Z1wbzYTkPEMm9NWcCJc0eXkXjJ948Ff76z4Axyh7QdbIuLq1gNL9FFtOCK4alcKUiGI zN/M/3t+tletcGx7nedSNDsEXBqwjTmm62R4PGnMev0gbdnSDTFfxMFrRg9jC3WY0mV2 YAOnKyhfkyhCaQ8fDxPRhYPxG4wSLl+xlmg6+GPsmGsu26lAjNkdZUuFt4LXTyAw1mw6 3dcYj9pFQ+MQuFEdMysaRlGNa+IA8ywK66VknIFv3ITpcwzPqsBYJSThyZ4papi0+teg yOlA== MIME-Version: 1.0 Received: by 10.50.41.165 with SMTP id g5mr11890503igl.13.1337752669238; Tue, 22 May 2012 22:57:49 -0700 (PDT) Received: by 10.64.12.205 with HTTP; Tue, 22 May 2012 22:57:49 -0700 (PDT) In-Reply-To: References: <72B744D5-3D24-4A56-907C-2A8F6620877B@FreeBSD.org> Date: Wed, 23 May 2012 11:27:49 +0530 Message-ID: From: Venkat Duvvuru To: Jack Vogel Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-net@freebsd.org, "Bjoern A. Zeeb" , freebsd-questions@freebsd.org Subject: Re: LRO support for IPv6 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 May 2012 05:57:50 -0000 Ok. I found the reason for the throughput drop in case of IPv6. Reason is that the "tcp check sum" calculation is mandated in case of IPv6 irrespective of whether the card is doing it or not (checksum offload). Is there a reason why freebsd is doing it that way? /Venkat On Tue, May 22, 2012 at 11:16 PM, Jack Vogel wrote: > LRO is a huge win for 10G (as is TSO on the TX side), so odds are good its > behind the drop, > in any case you'll be able to test that soon :) > > Jack > > > > On Tue, May 22, 2012 at 10:35 AM, Venkat Duvvuru < > venkatduvvuru.ml@gmail.com> wrote: > >> Thanks for the response. >> >> I observed that there is a significant performance drop in case of IPv6 >> on the "rx" side. >> While I'm able to hit line rate ~9.5 Gbps on a 10gb NIC for IPv4..I could >> only get ~6 Gbps on the "rx" front for IPv6...However "tx" for IPv6 is on >> par with IPv4 hitting almost line rates. >> >> Could this be because of lack of LRO6?? >> >> Note: hwpmc profiling shows that most of the time is spent in the IPv6 >> stack code >> >> /Venkat >> On Tue, May 22, 2012 at 10:37 PM, Bjoern A. Zeeb wrote: >> >>> >>> On 22. May 2012, at 17:04 , Jack Vogel wrote: >>> >>> > Oh, that's right, distracted with other projects and I forgot, now we >>> just need >>> > to have an LRO that works with forwarding eh :) >>> >>> That's a 6 line bainaid commit afterwards, basically returning form the >>> LRO queuing >>> function in case forwarding is turned on for that address family; a >>> proper solution >>> for long term can than be done whenever we feel like it. The above we >>> should have done >>> years ago;) >>> >>> >>> > You ROCK bz :) >>> > >>> > Jack >>> > >>> > >>> > On Tue, May 22, 2012 at 10:01 AM, Bjoern A. Zeeb >>> wrote: >>> > >>> > On 22. May 2012, at 16:50 , Jack Vogel wrote: >>> > >>> > > The LRO code as it stands right now is IPV4 specific, it would be >>> nice to >>> > > extend it, one of >>> > > many improvements that may get done at some point. >>> > >>> > I am about to commit it to HEAD. Bear another few days with me; I know >>> > I am running late but committing new code had less prio than some other >>> > real life things currently. >>> > >>> > I'll also bring TSO6, etc... >>> >>> -- >>> Bjoern A. Zeeb You have to have visions! >>> It does not matter how good you are. It matters what good you do! >>> >>> >> >