Good day,
I am writing here, as in technical support ticket I will most likely end
up to the outsourcing guys, who will try to write some formal reply and
close the ticket quickly to keep KPI high:)
I have a faint hope that someone will read and listen. It may also be
useful to colleagues.
I noticed at last few month, if some congestion occurs on the network
(specific subnet), facebook reduces the maximum segment size (MSS), even
down to 256 bytes. Purely academically, on paper - this will reduce
latency.
In reality - it will cause avalanche effect.
If ISP have CGNAT, or some other appliances - with great probability
they will encounter the fact that pps will increase 4-5 times, and might
hit pps limit on hardware. Additionally, overhead on IP headers will
increase significantly, especially on ipv6, and this will further
aggravate the congestion.
Facebook don't do that, please. And thank you, if you listen to
suggestions.
Denys
