IMPO, a replacement of the event counter by cumulative spin time does not look like "the equal swap". The replacement will hide some sense in system's behavior and in the nature of lock contention. So, adding the spin time to the metric of "spin count", but not replacing it, will realty provide a better picture to compare the results between systems.
Mikhail > This metric has been used in the past to diagnose certain performance > problems due to lock contention . However it has been of limited > usefulness. The metric of "spin count" does not provide an absolute > measure of overhead and cannot be used to compare between systems. > With the addition of exponential backoff optimizations, it becomes > even cruder because the number of spins is no longer linearly > proportional to the amount of time spent acquiring the lock. The > dtrace guide itself says: "The spin count has little meaning on its > own, but can be used to compare spin times." This message posted from opensolaris.org
