Intel processors offer PerfMon, a set of hardware events and counters that may be programmed in a number of ways for a variety of uses. Traditionally used for application optimization, we are seeing novel nascent uses throughout the software stack: in operating systems, virtualization hypervisors, and even BIOS firmware. Conflict for these counters has already been observed, and is likely to worsen. We posit the need for hardware features to allow “reservation” of and exclusive access to hardware counters, and describe a prototype system2 to solve the problem.
- Intel Labs: Rob Knauerhase, Paul Brett
- Intel Software and Services Group: Peggy Irelan