Networking scalability on high-performance servers
http://www.ibm.com/developerworks/linux/library/l-scalability/index.html?S_TACT=105AGX01&S_CMP=LP number of benchmarks of linux networking on SMP servers, with some tuning suggestions.
Testing
Networking scalability on high-performance servers
http://www.ibm.com/developerworks/linux/library/l-scalability/ How to avoid problems with Linux networking scalability on high-performance systems