High resolution timers (HRTs) bypass the traditional 10 millisecond clock interface to expose the granularity of the physical clock interrupt from the hardware. Thus, the HRT interface allows a real time process to take control of one processor (of a multi-processor system) and operate to any required degree of precision in timing events.
This is the last element needed to allow traditional real-time applications to be run under Solaris.
For more information, see the System Interface Guide.