[Bloat] excellent result with OpenWrt 18.06.1 + CAKE on FTTH

[Dave Taht]

On Mon, Nov 12, 2018 at 8:21 AM Mikael Abrahamsson <swmike at swm.pp.se> wrote:
>
> On Mon, 12 Nov 2018, Dave Taht wrote:
>
> > Don't use this connection much, do you? :)
>
> Last 4 week average is 300 kilobit/s up and 3000 kilobit/s down. So no.
> Mostly streaming Netflix and similar things.
>
> >>    marks             512
> >
> > and that you have at least one device with ecn enabled. Would this be
> > OSX or IOS perhaps?
>
> I typically turn it on on all devices I remember to turn it on. There are
> plenty of iOS devices in the household, but also ECN enabled OSX machines.
>
> > I don't suppose you have someone else "across town" you could run some
> > benchmarks against?
>
> Surely. I can run anything you need, I have 1GE ubuntu machine
> ~3ms away. What tests do you want me to run? I have ubuntu laptop here I
> can run wired tests with. It already has flent installed, so just tell me
> what you want me to do and test. If you want me to change qdisc settings
> I'm going to need good instructions, I am not proficient in changing those
> settings.

cake on or off would be a good start, then fq_codel with simple.qos.

irtt stats are more accurate at this high resolution,
irtt is now packaged and started automagically for ubuntu, and picked
up automatically by flent if available. do check to see if it's on
both boxes and that the relevant port is not firewalled.

#/bin/sh
F="flent -x -s .02" # run flent in high resolution - even 20ms samples
isn't good enough anymore!
S=your_server
T="a meaningful title"

$F -H $S -t "$T" rrul
$F -H $S -t "$T" rrul_be
$F -H $S -t "$T-100" -l 20 --socket-stats --te=upload_streams=100 tcp_nup
$F -H $S -t "$T-500" -l 20 --socket-stats --te=upload_streams=500 tcp_nup
$F -H $S -t "$T" --te=download_streams=100 tcp_ndown

Of these the most interesting one in cake's case is actually the
tcn_nup test, vs fq_codel, vs baseline

I note that -s .02 and socket stats will EAT GB of ram to process and
take minutes to finalize.

If you feel really ambitious, ecn/no behavior on your tcps on tcp_nup
is rather interesting at this load.

>
> > Similarly, a cpu number under load. I note here, that splitting GSO
> > has a big cost, (primarily in routing table lookup) and you can at
> > these speeds, probably disable it.
>
> sirq% peaks out around 35-40% when doing download at 250 megabit/s. Around
> 10% when doing upload at 100 megabit/s. Armada 385 is nice.

Yep. I've universaly switched to that on "the low end" when I can't
get an APU2.  If only the wifi was better.

> > I was also expecting 64k here. I imagine you are using modern linuxes
> > that don't overuse TSO anymore, and osx and windows never got into it to
> > the extreme that linux did.
>
> root at wrt1200-hemma:~# uname -a
> Linux wrt1200-hemma 4.14.63 #0 SMP Wed Aug 15 20:42:39 2018 armv7l GNU/Linux
>
>
>
> --
> Mikael Abrahamsson    email: swmike at swm.pp.se



-- 

Dave Täht
CTO, TekLibre, LLC
http://www.teklibre.com
Tel: 1-831-205-9740