Intel claims to implement 15H CPUID but usually leaves the ART crystal HZ in ECX blank, which makes the other fields useless. Invariant timestamps are available

Intel claims to implement 15H CPUID but usually leaves the ART crystal HZ in ECX blank, which makes the other fields useless. Invariant timestamps are available on all x86_64 CPUs except K8, but trying to convert them to nanoseconds is an even bigger shit show than clock_gettime.