Scalability and performance - Its all about the customers
Todd pinged me to see how I felt about antirez's suggession in his post titled " On the webserver scalability and speed are almost the same thing ". While I disagree with parts of the post, I can understand why he believed what he wrote. If someone were to design a state of the art scalable webserver in place of an existing service (lets say apache) which can deliver content in 50 ms, then by my definition the new webserver should continue to serve that content at 50 ms even if the number of requests handled per second by the service increases 100 times. Antirez's argument is somewhat correct that just because you can scale doesn't mean that customers will always forgive you for slower performance. But as it happens I've seen many different solutions in the last decade which ignored that concern and provided  a scalable yet slower service and still succeeded in generating enough revenue to prove that slower speed may not be a show stopper. In my opinion