ABSTRACT
Hardware performance counters are registers available on modern CPUs that count low-level events within the processor with minimal overhead. Hardware counters may also exist on other system components, such as memory controllers and network interfaces. Data from the counters can be used for performance evaluation and tuning. Each processor family has a different set of hardware counters, often with different names even for the same types of events. Models in the same processor family can also differ in the specific events available. In general similar types of events are available on most CPUs.
