[data from a 600Mhz Duron]

PERFCTR INIT: vendor 2, family 6, model 3, stepping 0, clock 605619 kHz
PERFCTR INIT: NITER == 64
PERFCTR INIT: loop overhead is 171 cycles
PERFCTR INIT: rdtsc cost is 13.9 cycles (1065 total)
PERFCTR INIT: rdpmc cost is 13.6 cycles (1043 total)
PERFCTR INIT: rdmsr (counter) cost is 51.8 cycles (3487 total)
PERFCTR INIT: rdmsr (evntsel) cost is 52.7 cycles (3550 total)
PERFCTR INIT: wrmsr (counter) cost is 81.6 cycles (5399 total)
PERFCTR INIT: wrmsr (evntsel) cost is 232.0 cycles (15025 total)
PERFCTR INIT: read cr4 cost is 2.2 cycles (314 total)
PERFCTR INIT: write cr4 cost is 62.8 cycles (4194 total)
PERFCTR INIT: sync_core cost is 70.6 cycles (4695 total)
perfctr: driver 2.7.9, cpu type AMD K7/K8 at 605619 kHz