Tuning Minecraft in the Fastest and Cheapest Way
If you want a Minecraft server to be cheap, small and very fast; especially for large servers… skip the SSD, video cards and other nonsense associated with a server. Besides a decent internet connection and reliable power, this is what has given me very good results in the past.
Cheap recent AMD or Intel single processor, more cores is OK.. just not more sockets because we want to localize the Java threads and their I/O to the processors L2 and L3 caches. Cheap hard disk or boot from USB to make this cheaper, but warning that USB is not typically as fast for backups and or installations such as Bukkit.
This is most important… Get 4-8GB of RAM, depending on if you are running a vanilla server or Bukkit in the latter. Run a RAMDISK such as DataRam on Windows> http://memory.dataram.com/products-and-services/software/ramdisk
Linux has a built in RAMDISK and there are solutions for Mac as well. Put the whole server on the RAMDISK and have it periodically write backups and/or stream its contents to disk (only needs to write changes) and set this to every 15 minutes or so for good data protection and keeping angry users to a minimum. Take daily or weekly backups to another computer or media somewhere. Losing data isn’t cool for you or your users.
Don’t use an SSD because in comparison to SSD’s hundreds of MB/second, GB/second is possible for the L2/L3 cache and memory boundaries if we leave disk out of the picture and relagate it to the role of backups. SSD or RAID may need to come into play on the largest Minecraft servers using database servers.