Here are my settings that I use to optimize my server for high bandwidth transfers, and heavy load.  Keep in mind these settings will definitely use more memory then default, so make sure you have a decent amount of memory.  Just place this file in /etc/sysctl.conf and reboot.   kern.maxfiles=25600 kern.maxfilesperproc=16384 kern.ipc.maxsockbuf=4194304 # (default 2097152)