Change default VFS timestamp precision?

[John Baldwin]

On Thursday, December 18, 2014 08:14:02 PM Poul-Henning Kamp wrote:
> --------
> 
> In message <77322.1418933100 at critter.freebsd.dk>, "Poul-Henning Kamp" 
writes:
> >>I don't understand
> >>why you think TSP_USEC is slower than TSP_NSEC.  microtime() and
> >>nanotime()
> >>both just call bintime() and then convert the result using similar math.
> >
> >Because of the pointless nano->micro conversion which makes TSP_USEC
> >take a division longer to deliver a less precise result than TSP_NSEC.
> 
> Actually, that's the other way around: it converts microseconds to
> nanoseconds with a pointless multiplication.

Yes, and multiplication is cheaper than division.  It's not a power of
two (so more than a single bitshift), but possibly in the noise compared
to the work in bintime() itself.

-- 
John Baldwin