I'm learning C/C++, tried to compile (http://ideone.com/T1xVLz) your code in ubuntu, with gcc-4.8, and an error about copy_n is not declared in this scope was raised.
error: ‘copy_n’ was not declared in this scope
what is the problem? Is it something to do with gcc-4.8 and shared libs?
I've successfully made one node server handle over 400K concurrent connections on a 24 core (4*6cores) and 32gb ram. Not with standard configs though. And I know there is more room to grow when the reverse-proxy gets out of the way. However this setup easily saturates 1gbs NIC, and never tested with dedicated 10gb uplink. If you are looking for ACID database application stack then you won't get anywhere near raw output anyway. So don't bother choosing any like you did. But If you are in the nosql business then you might get around some 10k iops with the right set of hardware and config tweaks.