These are my links for 20 ago 2013 from 02:47 to 02:50:

• WordPress › HyperDB « WordPress Plugins – HyperDB is a very advanced database class that replaces a few of the WordPress built-in database functions. The main differences are: * HyperDB can be connect to an arbitrary number of database servers, * HyperDB inspects each query to determine the appropriate database.
• ClusterFoundry Blog Highly-Available and Load-Balanced WordPress Cluster – Part 1 – This article explains on how to setup a load-balanced WordPress cluster in a master-slave configuration. The load balancer(HAProxy) sits in front of 2 or more web server nodes (1 Master and 1 Slave) which has the same contents. HAProxy does not only distribute requests, but also checks the health of the services running on the node. If one of the nodes are down, all requests will be redirected to the remaining nodes.
• Deploying Scalable WordPress – The Official Rackspace Blog – […] The end result is a WordPress site that uses Cloud Load Balancers, Cloud Servers, and Cloud Files to deliver an easily scalable, modular configuration.[…]