Abstract: The present invention provides for the hardware on-chip capturing and storage of performance count data about software programs running on the chip. Counters generate performance data about the programs, and the values of the counters are stored in a trace array. In an embodiment, instruction addresses and other data can be written along with the performance count data. In an embodiment, the data can be may be buffered and streamed to an external memory or device. In an embodiment, interval counters control the writing of the performance count data to the trace array.