With today’s multi-socket, multi-core, highly-threaded PowerEdge servers, the operating system, applications, and drivers are expected to be written to take advantage of this massively parallel architecture.
Update May 2012: We now have the low latency whitepaper updated for PowerEdge 12th Generation Servers:
Link to blog
Link to whitepaper
Update Nov 2012: Limiting processor C-state usage by the OS is often desirable in latency-sensitive environments. A brief white paper discussing the ways of controlling C-state usage in linux is available here.