Identifying Derived Performance Requirements of System Components from Explicit Customer- and Application- Facing Performance Requirements

Explicitly stated response time, throughput, and other performance requirements of an application implicitly impose other performance requirements on the system components that implement it. We call these derived performance requirements. The explicit performance requirements cannot be met if the derived performance requirements are not met. Explicit performance requirements naturally give rise to corresponding derived performance requirements expressed in terms of the same metrics. Derived performance requirements may also be identified that specify the sizes of object pools or the amount of memory needed to meet explicit and other derived requirements. Moreover, derived requirements may be identified that depend on the implementation of the components. We explore how derived requirements arise and present a methodology for identifying and specifying them.