From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-x229.google.com (mail-ie0-x229.google.com [IPv6:2607:f8b0:4001:c03::229]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 1CB0321F42A for ; Thu, 13 Nov 2014 20:37:35 -0800 (PST) Received: by mail-ie0-f169.google.com with SMTP id y20so355703ier.14 for ; Thu, 13 Nov 2014 20:37:35 -0800 (PST) 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=RdfCif3b+jLyLlcHbfS/vi+8BABa3YS36pePUAI7YKY=; b=Bl9ArjfqQuJTSa/hZBSPHArPpgFziIagMgpbid6l9a4zmsbjj5YyzNjTM07lbbCCQ7 pbCc3dlAT62wOU8LRpJLucM0Fkk2lvjo/Mop/kTgCE9T6A6M6LcJmPbr0DYzDbKJLuf+ Q62uRWLcnAmYm7rUV/nocIEbIzkLXARAFpYpxZlFRmuSosSLJRa5Rbs8mjWWkFzY3gYe BSmBWdk5AB0uCW+MC5IzzneskAjRsknYyHNQTaUmfWQTAVg5nfYhPLfw7yBiuD/Hc7YW VICTr71XBbjq8UVKNCj9VRIga24OM6jSjYr4qbLlPxkYkgwVrpR/WCzoBNE6M4tB5RzD /OGA== MIME-Version: 1.0 X-Received: by 10.50.137.65 with SMTP id qg1mr3453287igb.37.1415939855005; Thu, 13 Nov 2014 20:37:35 -0800 (PST) Received: by 10.64.11.102 with HTTP; Thu, 13 Nov 2014 20:37:34 -0800 (PST) In-Reply-To: References: Date: Thu, 13 Nov 2014 20:37:34 -0800 Message-ID: From: Aaron Wood To: Dave Taht Content-Type: multipart/alternative; boundary=001a11c3e48014c19f0507ca30c7 Cc: Frank Horowitz , "cerowrt-devel@lists.bufferbloat.net" Subject: Re: [Cerowrt-devel] High Performance (SSH) Data Transfers using fq_codel? X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Nov 2014 04:38:04 -0000 --001a11c3e48014c19f0507ca30c7 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable I have a couple friends in that crowd, and they _also_ aren't using shared lines. So they don't worry in the slightest about congestion when they're trying to keep dedicated links fully saturated. They're big issue with dropped packets is that some of the TCP congestion-control algorithms kick in on a single dropped packet: http://fasterdata.es.net/network-tuning/tcp-issues-explained/packet-loss/ I'm thinking that some forward-error-correction would make their lives much, much better. -Aaron On Thu, Nov 13, 2014 at 7:11 PM, Dave Taht wrote: > One thing the HPC crowd has missed is that in their quest for big > buffers for contenental distances, they hurt themselves on shorter > ones... > > ... and also that big buffers with FQ on them works just fine in the > general case. > > As always I recomend benchmarking - do a rrul test between the two > points, for example, with their recomendations. > > > On Fri, Oct 17, 2014 at 4:21 PM, Frank Horowitz wrote: > > G=E2=80=99Day folks, > > > > Long time lurker. I=E2=80=99ve been using Cero for my home router for q= uite a > while now, with reasonable results (modulo bloody OSX wifi stuffola). > > > > I=E2=80=99m running into issues doing zfs send/receive over ssh across = a > (mostly) internet2 backbone between Cornell (where I work) and West > Virginia University (where we have a collaborator on a DOE sponsored > project. Both ends are linux machines running fq_codel configured like so= : > > tc qdisc > > qdisc fq_codel 0: dev eth0 root refcnt 2 limit 10240p flows 102= 4 > quantum 1514 target 5.0ms interval 100.0ms ecn > > > > I stumbled across hpn-ssh and > =E2=80=94 of particular interest to this group =E2=80=94 their page on t= uning TCP > parameters: > > > > > > > > N.B. their advice to increase buffer size=E2=80=A6 > > > > I=E2=80=99m curious, what part (if any) of that advice survives with fq= _codel > running on both ends? > > > > Any advice from the experts here would be gratefully received! > > > > (And thanks for all of your collective and individual efforts!) > > > > Cheers, > > Frank Horowitz > > > > > > _______________________________________________ > > Cerowrt-devel mailing list > > Cerowrt-devel@lists.bufferbloat.net > > https://lists.bufferbloat.net/listinfo/cerowrt-devel > > > > > > -- > Dave T=C3=A4ht > > thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks > _______________________________________________ > Cerowrt-devel mailing list > Cerowrt-devel@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cerowrt-devel > --001a11c3e48014c19f0507ca30c7 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I have a couple friends in that crowd, and they _also_ are= n't using shared lines.=C2=A0 So they don't worry in the slightest = about congestion when they're trying to keep dedicated links fully satu= rated.=C2=A0 They're big issue with dropped packets is that some of the= TCP congestion-control algorithms kick in on a single dropped packet: =C2= =A0http://fasterdata.es.net/network-tuning/tcp-issues-explained/= packet-loss/

I'm thinking that some forward-erro= r-correction would make their lives much, much better.

=
-Aaron

On Thu, Nov 13, 2014 at 7:11 PM, Dave Taht <dave.taht@gmail.com> wrote:
One thing the HPC cro= wd has missed is that in their quest for big
buffers for contenental distances, they hurt themselves on shorter
ones...

... and also that big buffers with FQ on them works just fine in the
general case.

As always I recomend benchmarking - do a rrul test between the two
points, for example, with their recomendations.


On Fri, Oct 17, 2014 at 4:21 PM, Frank Horowitz <frank@horow.net> wrote:
> G=E2=80=99Day folks,
>
> Long time lurker. I=E2=80=99ve been using Cero for my home router for = quite a while now, with reasonable results (modulo bloody OSX wifi stuffola= ).
>
> I=E2=80=99m running into issues doing zfs send/receive over ssh across= a (mostly) internet2 backbone between Cornell (where I work) and West Virg= inia University (where we have a collaborator on a DOE sponsored project. B= oth ends are linux machines running fq_codel configured like so:
>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0tc qdisc
>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0qdisc fq_codel 0: dev eth0 root refcn= t 2 limit 10240p flows 1024 quantum 1514 target 5.0ms interval 100.0ms ecn<= br> >
> I stumbled across hpn-ssh <https://www.psc.edu/index.php/hpn-ssh> a= nd =E2=80=94=C2=A0 of particular interest to this group =E2=80=94 their pag= e on tuning TCP parameters:
>
> <http://www.psc.edu/index.php/networking/641-tcp-tune&g= t;
>
> N.B. their advice to increase buffer size=E2=80=A6
>
> I=E2=80=99m curious, what part (if any) of that advice survives with f= q_codel running on both ends?
>
> Any advice from the experts here would be gratefully received!
>
> (And thanks for all of your collective and individual efforts!)
>
> Cheers,
>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0Frank Horowitz
>
>
> _______________________________________________
> Cerowrt-devel mailing list
> Cerowrt-devel@l= ists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/cerowrt-devel
>



--
Dave T=C3=A4ht

thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_T= alks
_______________________________________________
Cerowrt-devel mailing list
Cerowrt-devel@lists.= bufferbloat.net
https://lists.bufferbloat.net/listinfo/cerowrt-devel

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