Initially, The Pirate Bay's four Linux servers ran a custom web server called Hypercube. An old version is open-source. On 1 June 2005, The Pirate Bay updated its website in an effort to reduce bandwidth usage, which was reported to be at 2 HTTP requests per millisecond on each of the four web servers, as well as to create a more user friendly interface for the front-end of the website. The website now runs Lighttpd and PHP on its dynamic front ends, MySQL at the database back end, Sphinx on the two search systems, memcached for caching SQL queries and PHP-sessions and Varnish in front of Lighttpd for caching static content. , The Pirate Bay consisted of 31 dedicated servers including nine dynamic web fronts, a database, two search engines, and eight BitTorrent trackers.