[data from a 1.4 GHz Pentium III (Tualatin)]

PERFCTR INIT: vendor 0, family 6, model 11, stepping 1, clock 1396448 kHz
PERFCTR INIT: NITER == 64
PERFCTR INIT: loop overhead is 91 cycles
PERFCTR INIT: rdtsc cost is 36.7 cycles (2441 total)
PERFCTR INIT: rdpmc cost is 33.1 cycles (2212 total)
PERFCTR INIT: rdmsr (counter) cost is 90.4 cycles (5879 total)
PERFCTR INIT: rdmsr (evntsel) cost is 71.9 cycles (4694 total)
PERFCTR INIT: wrmsr (counter) cost is 100.7 cycles (6539 total)
PERFCTR INIT: wrmsr (evntsel) cost is 96.0 cycles (6241 total)
PERFCTR INIT: read cr4 cost is 1.9 cycles (215 total)
PERFCTR INIT: write cr4 cost is 42.2 cycles (2796 total)
perfctr: driver 2.4.1, cpu type Intel Pentium III at 1396448 kHz