From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-x230.google.com (mail-oi0-x230.google.com [IPv6:2607:f8b0:4003:c06::230]) (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 C6E2B21F94C for ; Sat, 31 Oct 2015 13:29:07 -0700 (PDT) Received: by oiao187 with SMTP id o187so76912469oia.3 for ; Sat, 31 Oct 2015 13:29:06 -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:content-transfer-encoding; bh=oq4VBeNN2iatwTwWjmozQV6cUJew2d1bXIigwoM2bWA=; b=jM55NOmBJFYGCU3ARu9kea+v98kM6Qx4d2SNcYP1IKpjI9Zi+YipvWqPNXnNin+iXX IpFJUQZpR70mHDN25T2dzUTG5+P1QbhSlsE8WhxiWAtmjWXZCZGghhlyH0ARAJaZNPH4 NXxWwzG2E9dEBv97YiZVV9010L7zhnlWMnisLGLhd1V9qqzN6opCik7Fa12r/yPxRHV/ PPDSgNu2MeDelZvGHksxp0lOrYSGEUYDGd8U/8JLZzWUR5lbH3jfUxWXi2SbMci8kEJX hirCoIkOJijceDeKhS0c4vgVOHVY2YPKLDVesoF/VzS8WZoHAZxaFDsg7RVr5aPDmDkP g/ww== MIME-Version: 1.0 X-Received: by 10.202.221.68 with SMTP id u65mr9535989oig.34.1446323346546; Sat, 31 Oct 2015 13:29:06 -0700 (PDT) Received: by 10.202.61.133 with HTTP; Sat, 31 Oct 2015 13:29:06 -0700 (PDT) In-Reply-To: <563517E5.4050202@darbyshire-bryant.me.uk> References: <563517E5.4050202@darbyshire-bryant.me.uk> Date: Sat, 31 Oct 2015 16:29:06 -0400 Message-ID: From: Dave Taht To: Kevin Darbyshire-Bryant Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Cc: cake@lists.bufferbloat.net Subject: Re: [Cake] Stranger target behaviour X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 31 Oct 2015 20:29:30 -0000 The second one is from the interval >> 4, which equates to 6.2ms. I note I picked that because some early data (2012) we had showed that target slightly greater than cable media acquision (6ms) time was a slight win, and it did not hurt to use a number more evenly divisible in binary than the arbitrary 5%. Also there was somewhere else in the original code where I'd stopped using the target variable entirely and just used the shifted interval, but given low rates where we have to account for the MTU, that approach does not work. (otherwise anytime I can replace a memory access with a mere shift, I'd do it) As for the first 5ms sample below, I am really behind on keeping up with the code. After next weekend I would hope to have time, but I do hope someone can step through all the permutations upon which init and change can be called to nail it. Somewhere on these threads someone suggested moving the target calculation into userspace, which does not work well, IMHO, when cake is the default qdisc, and we somehow get a means to actually get the actual line rate. Dave T=C3=A4ht I just invested five years of my life to making wifi better. And, now... the FCC wants to make my work, illegal for people to install. https://www.gofundme.com/savewifi On Sat, Oct 31, 2015 at 3:35 PM, Kevin Darbyshire-Bryant wrote: > Playing with latest JM authed commits on sch-cake & tc-adv. Look at the > target values: > > root@Router:~# tc -s qdisc change dev ifb4eth0 root cake internet > root@Router:~# tc -s qdisc show dev ifb4eth0 > qdisc cake 8008: root refcnt 2 bandwidth 39300Kbit diffserv4 flows rtt > 100.0ms noatm overhead 12 > Sent 285837 bytes 1240 pkt (dropped 0, overlimits 144 requeues 0) > backlog 0b 0p requeues 0 > capacity estimate: 10511Kbit > Tin 0 Tin 1 Tin 2 Tin 3 > thresh 39300Kbit 36843Kbit 29475Kbit 9825Kbit > target 5.0ms 5.0ms 5.0ms 5.0ms > interval 100.0ms 100.0ms 100.0ms 100.0ms > Pk-delay 0us 22us 0us 0us > Av-delay 0us 6us 0us 0us > Sp-delay 0us 2us 0us 0us > pkts 0 1240 0 0 > bytes 0 285837 0 0 > way-inds 0 0 0 0 > way-miss 0 125 0 0 > way-cols 0 0 0 0 > drops 0 0 0 0 > marks 0 0 0 0 > Sp-flows 0 0 0 0 > Bk-flows 0 2 0 0 > last-len 0 82 0 0 > max-len 0 1514 0 0 > > root@Router:~# tc -s qdisc change dev ifb4eth0 root cake rtt 100ms > root@Router:~# tc -s qdisc show dev ifb4eth0 > qdisc cake 8008: root refcnt 2 bandwidth 39300Kbit diffserv4 flows rtt > 100.0ms noatm overhead 12 > Sent 757689 bytes 2374 pkt (dropped 0, overlimits 464 requeues 0) > backlog 0b 0p requeues 0 > capacity estimate: 5964Kbit > Tin 0 Tin 1 Tin 2 Tin 3 > thresh 39300Kbit 36843Kbit 29475Kbit 9825Kbit > target 6.2ms 6.2ms 6.2ms 6.2ms > interval 100.0ms 100.0ms 100.0ms 100.0ms > Pk-delay 0us 286us 0us 0us > Av-delay 0us 70us 0us 0us > Sp-delay 0us 2us 0us 0us > pkts 0 2374 0 0 > bytes 0 757689 0 0 > way-inds 0 0 0 0 > way-miss 0 157 0 0 > way-cols 0 0 0 0 > drops 0 0 0 0 > marks 0 0 0 0 > Sp-flows 0 0 0 0 > Bk-flows 0 2 0 0 > last-len 0 82 0 0 > max-len 0 1514 0 0 > > Colour me confused :-) > > Kevin > > > _______________________________________________ > Cake mailing list > Cake@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/cake >