|
Abstract : |
1 Cache Memories and Real-Time Applications Caches are used to improve the access times of fast microprocessors to relatively slow main memories. They can reduce the number of cycles a processor is waiting for data by providing faster access to recently referenced regions of memory1. Programs with hard real time constraints have to be subjected to a schedulability analysis by the compiler [17, 6]; it has to be determined whether all timing constraints can be satisfied. WCETs (Worst Case Execution Times) for processes have to be used for this. For hardware with caches, the appropriate worst case assumption is that all accesses miss the cache. This is an overly pessimistic assumption which leads to a waste of hardware resources. 1 Hennessy and Patterson [8] describe typical values for caches in 1990 workstations, |
