5 Tips for Sphinx Indexing | Engine Yard Blog
http://www.engineyard.com/blog/2009/5-tips-for-sphinx-indexing/
10 Years of Virtual Machine Performance (Semi) Demystified | Engine Yard Blog
http://www.engineyard.com/blog/2009/10-years-of-virtual-machine-performance-semi-demystified/

Since 2005, VMware and Xen have gradually reduced the performance overheads of virtualization, aided by the Moore’s law doubling in transistor count, which inexorably shrinks overheads over time. AMD’s Rapid Virtualization Indexing (RVI – 2007) and Intel’s Extended Page Tables (EPT – 2009) substantially improved performance for a class of recalcitrant workloads by offloading the mapping of machine-level pages to Guest OS “physical” memory pages, from software to silicon. In the case of operations that stress the MMU—like an Apache compile with lots of short lived processes and intensive memory access—performance doubled with RVI/EPT. (Xen showed similar challenges prior to RVI/EPT on compilation benchmarks.)