From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-03-ewr.dyndns.com (mxout-049-ewr.mailhop.org [216.146.33.49]) by lists.bufferbloat.net (Postfix) with ESMTP id B16E92E0726 for ; Sun, 20 Mar 2011 15:47:20 -0700 (PDT) Received: from scan-02-ewr.mailhop.org (scan-02-ewr.local [10.0.141.224]) by mail-03-ewr.dyndns.com (Postfix) with ESMTP id 0493E789109 for ; Sun, 20 Mar 2011 22:47:20 +0000 (UTC) X-Spam-Score: 0.1 () X-Mail-Handler: MailHop by DynDNS X-Originating-IP: 75.145.127.229 Received: from gw.co.teklibre.org (75-145-127-229-Colorado.hfc.comcastbusiness.net [75.145.127.229]) by mail-03-ewr.dyndns.com (Postfix) with ESMTP id 0C824788C47; Sun, 20 Mar 2011 22:47:18 +0000 (UTC) Received: from cruithne.co.teklibre.org (unknown [IPv6:2002:4b91:7fe5:1::20]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "cruithne.co.teklibre.org", Issuer "CA Cert Signing Authority" (verified OK)) by gw.co.teklibre.org (Postfix) with ESMTPS id 7D7055E88A; Sun, 20 Mar 2011 16:47:17 -0600 (MDT) Received: by cruithne.co.teklibre.org (Postfix, from userid 1000) id 57394120889; Sun, 20 Mar 2011 16:47:16 -0600 (MDT) From: d@taht.net (Dave =?utf-8?Q?T=C3=A4ht?=) To: Jonathan Morton Organization: Teklibre - http://www.teklibre.com References: <0D59AD34-AA64-4376-BB8E-58C5D378F488@gmail.com> <4D829B58.1070601@swin.edu.au> <4D8664A9.5060805@swin.edu.au> <87k4fte83o.fsf@cruithne.co.teklibre.org> Date: Sun, 20 Mar 2011 16:47:16 -0600 In-Reply-To: <87k4fte83o.fsf@cruithne.co.teklibre.org> ("Dave =?utf-8?Q?T?= =?utf-8?Q?=C3=A4ht=22's?= message of "Sun, 20 Mar 2011 16:32:27 -0600") Message-ID: <87ei61e7ez.fsf@cruithne.co.teklibre.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: bloat-devel , bloat Subject: Re: [Bloat] Progress with latency-under-load tool X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 20 Mar 2011 22:47:21 -0000 d@taht.net (Dave T=C3=A4ht) writes: > The interesting outlier thus far is 8... I'm tempted to stop the test > now and recompile for testing 3 u/l 3 d/l first.... Scenario 12: 2 uploads, 2 downloads... 4725 KiB/s up, 3645 KiB/s down, 0.81= Hz smoothness ... Still running tests ... > Txqueuelen =3D 1000 =3D ~1.5Mbyte (and I'm struggling with using consiste= nt > decimal or base 2 units this month) Mibibyte? > > Normal dma tx ring size ranges from 64 to 512, can be seen sometimes > with ethtool -g device With wireless you also have TX_RETRIES =3D 13 for these (ath9) devices drivers under test. (Reduced to 4 in the less bloated version I can't test right now) You also have contention from other devices, and the occasional complete retrain from a base figure of 1Mbit/sec up, while devices struggle to regain sync. There are (presumably helpful) effects of packet aggregation. You also have modulo issues against the size of the tx queues, an interaction with the network flow scheduler (what triggers filling the tx queue?), SACK/DSACK and lost ACK retransmits, and probably more issues than I've been able to come up with offhand. --=20 Dave Taht http://nex-6.taht.net