[tostitos1979]

I suggest you look for slides from the Whatsapp folks on the kernel and Beam vm tuning they did to get similar numbers. Don't have the link handy but fairly easy to find.

What is more problematic IMHO is generating the load to saturate said server.

[davidw]

IIRC, the Whatsapp folks use FreeBSD.

[mickael]

We manage to load the server properly with Tsung (https://github.com/processone/tsung) but for a more heavy load we may need to add one more Tsung server.