memcached. It’s basically a system that uses hash tables to serve content directly from memory rather than from disk.
It’s used by all the big boys, e.g. Facebook, Digg, Reddit, etc.
Facebook has some sick stats around it, actually: They have 200 Memcache servers, all of which have 16GB of RAM, hosting a 2TB Memcache table.
And my decision to mess with this couldn’t have come at a better time: Linode just upgraded everyone’s RAM, so I went up by 100MB of memory, and down in price by like $40.
Anyway, let me know if you see any speed improvements on the site.
[ 2010-06-19 : Check out my site load stats from Chartbeat. ]