Re:Serving Netflix Video at 400Gb/s on FreeBSD [pdf]
by allanjude on Sunday September 19, 2021 @06:52PM
(#28588682)
In previous talks Netflix has mentioned that due to serving so many 1000s of people from each box, that they basically do 0 caching in memory, all of the system memory is needed for buffers that are enroute to users, and they purposely avoid keeping any buffer cache beyond what is needed for sendfile()
It would be fascinating to hear from Netflix on some serious details of the usage patterns they see and particular optimizations that they do for that, but I doubt there's so much they can do given the size of the streams, the 'randomness' of what people watch and when they watch, and for the fact that the linked slides say the servers have 18x2TB NVME drives per-server and 256GB.
I wouldn't be surprised if the Netflix logo opener exists once on disk instead of being the first N seconds of every file though.