Hardware Constraints to Scaling
The design and implementation of the hardware will have a substantial impact on the scaling of applications run on it. There are three critical areas that can make a large difference to scaling. The amount of bandwidth to cache and the memory will be divided among the active threads on the system. The design of the caches will determine how much time is lost because of capacity and conflict-induced cache misses. The way that the processor core pipelines are shared between active software threads will determine how instruction issue rates change as the number of active threads increases.