It isn't solely a file server. I made it to take over Linux workstation duties from my workstation (which now runs Windows 8.1, which, tbh, really isn't nearly as bad as everyone says it is), and it runs VMs for clustered software testing and development.

I export /home and /tank via Samba[1] to the now-Windows workstation (and sshfs for my OSX running MBP, which I may transition to Samba now) and get about 85% of Gigabit in performance, which is good enough for purely file storage tasks, although I'm considering dropping in 10gbit into both machines via http://www.provantage.com/~7MLNX1KC.htm (the cheapest 10gbit cards I've seen that aren't used pulls on ebay) if I start making bigger test clusters that run on both my workstation and my server.

Workstation has 2x Crucial M500 960GB RAID 1 (was BTRFS RAID 1, now is Intel Matrix FakeRAID RAID 1 in Windows), for the record.

[1]: For each share: aio read size = 1, aio write size = 1, use sendfile = yes, min recievefile size = 1, socket options = SO_KEEPALKIVE TCP_NODELAY IPTOS_THROUGHPUT

Do not mess with SO_SNDBUF and SO_RECVBUF for socket options, the default seems to already be the maximum size allowable on Linux.