This talk will describe a linux-based open source architecture designed to serve up a Drupal application in a high-performance way. It will cover reverse proxy caches (Varnish), Apache vs. nginx, the APC opcode cache, memcache and redis, expanding the stack across clusters, and MySQL database replication. The "mercury stack" will be covered, along with tweaks and changes that have become standard since it was first described. A series of block diagrams of a single server, small cluster, and large cluster will be shown and explained.

At the end we will discuss some of the hard scaling problems that don't have standard solutions yet - clustered file storage, large database write loads, etc. Possible approaches to those problems will be described.