End-to-end performance of commercial applications in the face of changing hardware

This paper investigates the changes in AIX behavior, or the lack of them, and the resulting performance impact from a generational change in servers in a typical large scale eCommerce application environment without extensive tuning of the OS and the application stack for the changing hardware. We have investigated the performance and impediments to performance at the microprocessor level and at the OS level. This paper dissects the performance data as observed from the OS and from hardware performance counters, and suggests areas for further improvements.