On 11 June 2010 16:11, Steven McCoy <[email protected]> wrote:

> "It takes 324 cycles per call to complete 1 million GTOD calls without
> RDTSCP and 221 cycles per call with the capability."
>
>
>
Compare this with HPET which I clock about 500ns when using mmap(), it would
be significantly slower when using libc IO to read from the device.

WIthout RDTSCP or HPET you can use CPUID+RDTSC or complicated tracking of
current cores and TSC offsets, etc, which is absolutely broken on
hyperthreading processors.

-- 
Steve-o
_______________________________________________
zeromq-dev mailing list
[email protected]
http://lists.zeromq.org/mailman/listinfo/zeromq-dev

Reply via email to