Re: [Bloat] Best practices for paced TCP on Linux?

[Dave Taht <dave.taht@gmail.com>]

Incidentally, I need to correct something I said earlier, in that I
noted that CS5 marking over ipv6 didn't survive the trip to NZ.

It turned out that I'd changed the port number and wasn't marking that
correctly.
That reduces my data set for that statistic to 0. (it WAS 3AM, forgive me)

I note that doing this marking internally at the event for wifi would
be a bad thing due to the characteristics of the VI queue, but perhaps
marking such for e2e externally on the tcp stream might help (and the
survival rate of that marking particularly for ipv6 and 6in4,6to4)
would be interesting too)

for the port I was using...

ip6tables -t mangle -I POSTROUTING -p udp -m multiport --ports 1234 -j
DSCP --set-dscp-class CS5

would have been correct

for the tcp streams in play here:

ip6tables -t mangle -I POSTROUTING -o whatever_the_right_interface_is
-p tcp -m multiport --ports 80,9094  -j DSCP --set-dscp-class CS5
iptables -t mangle -I POSTROUTING -o whatever_the_right_interface_is
-p tcp -m multiport --ports  80,9094 -j DSCP --set-dscp-class CS5


On Sat, Apr 7, 2012 at 8:35 AM, Steinar H. Gunderson
<sgunderson@bigfoot.com> wrote:
> On Sat, Apr 07, 2012 at 08:25:18AM -0700, Dave Taht wrote:
>> The test HD tcp stream is up at
>>
>> http://cesur.tg12.gathering.org:9094/
>
> That's the SD stream. http://stream.tg12.gathering.org/ has HD etc.
>
>> I'd like to look into what percentage of the failures I observed
>> happened on the wifi hop vs the ethernet gateway
>> since then many changes where made, and I'm low on sleep. (what do
>> geeks do on a friday night?)
>
> FWIW, most of the users complaining don't have wifi in the mix at all.
>
>> I don't know if they are still trying sfqred or qfq in production -
>> they worked! - but had little effect (as is to be kind of expected
>> with the instantaneous queue length being so short and bandwidth so
>> high on their first and nearest hops....)
>
> The one on cesur.tg12 has sfqred + my hacked VLC to do TCP pacing.
>
> The one on stream.tg12 has the oddest “shaping” in a while; the 10GigE is
> terminated in a Cisco 4948E which then has a 8x1GigE trunk out. We hope this
> will smooth out the worst bursts a bit.
>
> /* Steinar */
> --
> Homepage: http://www.sesse.net/



-- 
Dave Täht
SKYPE: davetaht
US Tel: 1-239-829-5608
http://www.bufferbloat.net