From owner-freebsd-net@FreeBSD.ORG Tue Jul 29 04:03:14 2014 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id A9CDFF78 for ; Tue, 29 Jul 2014 04:03:14 +0000 (UTC) Received: from mail-wg0-x231.google.com (mail-wg0-x231.google.com [IPv6:2a00:1450:400c:c00::231]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 31EFE2F7F for ; Tue, 29 Jul 2014 04:03:14 +0000 (UTC) Received: by mail-wg0-f49.google.com with SMTP id k14so8231180wgh.32 for ; Mon, 28 Jul 2014 21:03:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:reply-to:date:message-id:subject:from:to:content-type; bh=bUklx9HZB5IdL4nHgkGzGtZ2hM2tE0wJhCmLmxun5sE=; b=JCwGmTcLadMWtz44wOZbGU+6jA+v0oa0BUvjgjCvKJU+R0TEj/lIDnG6TEGJ7QBthx h5Vp1JAp5/i5a/j2Wm/fOJ/NSSvQGvl+TCQk3yJh04aBXW74FqvStDB3qDMY1+AuKiyq edzaOAO4kfCbL57Y2fBDCvchsDSapjUGqJIRDbOxE/hBqL+sGBfcimo3rtE2revfRbqy QIs9fmml1Z4FMPPKEtnQthxDGE8liqMU1MEL8xGRrsHf5iW2w52BN45hKtNmioDmmXnb qDMPup6t9M0o0POMP8WpIZrZp34L81nzu4TLGHmK8uR/yKr5tTv3MedG4Pn0+p2eGFZi +jyA== MIME-Version: 1.0 X-Received: by 10.194.219.193 with SMTP id pq1mr21510090wjc.5.1406606592234; Mon, 28 Jul 2014 21:03:12 -0700 (PDT) Received: by 10.216.159.136 with HTTP; Mon, 28 Jul 2014 21:03:12 -0700 (PDT) Reply-To: araujo@FreeBSD.org Date: Tue, 29 Jul 2014 12:03:12 +0800 Message-ID: Subject: Re: [patch][lagg] - Set a better granularity and distribution on roundrobin protocol. From: Marcelo Araujo To: FreeBSD Net Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 29 Jul 2014 04:03:14 -0000 > > > > > > 2014-07-19 2:18 GMT+08:00 Navdeep Parhar > >: > > > > On 07/18/14 00:49, Marcelo Araujo wrote: > > > Hello guys, > > > > > > I made few changes on the lagg(4) patch. Also, I made tests using > > igb(4), > > > ixgbe(4) and em(4); seems everything worked pretty well. > > > > > > I'm wondering if anyone else could make a review, and what I need > > to do, to > > > see this patch committed. > > > > Deliberately putting out-of-order packets on the wire is never a good > > idea. This would count as a serious regression in lagg(4) imho. > > > > Regards, > > Navdeep > > > > > > > > I'm wondering if anyone have tested the patch; because as I have > > explained in another email, the number of SACK is much less with this > > patch. I have put some pcap files > > here: http://people.freebsd.org/~araujo/lagg/ > > > > Also, as far as I know, the current roundrobin implementation has no > > such kind of mechanism to control the order of the packages that goes to > > the wire. And this patch, what it only does is, instead to send only one > > package through one interface and switch to the another one, it will > > send X(where X is the number of packets defined via sysctl) packets and > > then, switch to the next interface. > > > > So, could you show me, where this patch deliberately put out-of-order > > packets? Did I miss anything? > Hey np@ > > Are you saying lagg's roundrobin implementation is already spraying > packets for the same flow across interfaces? Yes it does, if you check the SACK counter you can see that it does out of order by itself, with the patch or without the patch. The only thing that this patch helps is, send more packets throughout an interface before switch to the next one, and we will end up with less SACK and a better throughput, and also we can make a fine tuning. > That would make it > unsuitable for anything TCP. This is something that everybody knows, it breaks TCP by itself, I mean, performance will drop. > But then your patch isn't making it any > worse so I don't have any objection to it any more. > Thank you so much, and sorry by my late reply, I got busy testing other things. > > Looks like loadbalance does the right thing for flows. > Yes, loadbalance has no issue, it is mainly on round robin. Best Regards, -- Marcelo Araujo (__)araujo@FreeBSD.org \\\'',)http://www.FreeBSD.org \/ \ ^ Power To Server. .\. /_)