Traditional software controlled data cache prefetching is often ineffective due to the lack of runtime cache miss and miss address information. To overcome this limitation, we implement runtime data cache prefetching in the dynamic optimization system ADORE (ADaptive Object code Reoptimization). Its performance has been compared with static software prefetching on the SPEC2000 benchmark suite. Runtime cache prefetching shows better performance. On an Itanium 2 based Linux workstation, it can increase performance by more than 20% over static prefetching on some benchmarks. For benchmarks that do not benefit from prefetching, the runtime optimization system adds only 1%-2% overhead. We have also collected cache miss profiles to guide static data cache prefetching in the ORC compiler. With that information the compiler can effectively avoid generating prefetches for loops that hit well in the data cache.

WC describe PRMS an animated simulation of process and resource management in a multi-programming operating system.PRMS was developed to illustrate important operating system concepts including process creation, process state transition, context switching, process scheduling, resource scheduling, interrupt handling, and deadlock detection and recovery.The users write their own, programs in a specified format, submit these to the system for execution, and monitor "behind the scenes" mechanisms and the behavior of the system on the screen.In addition to illustrating and reinforcing operating system concepts, PRMS can also be used for course projects by having the students change an algorithm such as the CPU scheduling algorithm or memory management scheme or add new features such as device interrupts to the system.