Erk, Avalanche is not as nice as I originally thought. It seems that it tries too hard to keep an average load rate. When responses take too long to return, it sends out more requests. The end result is that it overloads the application server. Damn it, why can't someone write a testing tool that sends out requests at a specified rate. Oh, hang on, that's what Thumper is supposed to do. Better get off my ass ....