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To: Kenneth Porter <shiva@sewingwitch.com>, bloat <bloat@lists.bufferbloat.net>
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Date: Sun, 06 Dec 2020 13:15:25 +0100
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Subject: Re: [Bloat] Xfinity Flex streaming box starves on cake?
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Kenneth Porter <shiva@sewingwitch.com> writes:

> I suspect that my Xfinity Flex box has too small an internal buffer and is 
> starving when fed by my cake-enabled OpenWrt router.

>From your config you have around 10x the downstream bandwidth you need
for streaming, so unless you are really hitting your connection hard
with other things I would not expect packets to buffer in the
modem/router at all while you're streaming.

So if this really is caused by sqm-scripts (which I think you should do
a few more tests to definitely confirm), I would think it more likely it
was due to some other weird interaction. Streaming box expecting a
certain DSCP marking? Server choking on ACK stream due to filtering?
Hard to say... A packet dump of the stream going to the box while the
black screen happens may be illuminating, but could be hard to pull off
if it's not reliably reproducible...

-Toke