On 11/29/18 11:14 AM, vincentfu@xxxxxxxxx wrote: > From: Vincent Fu <vincent.fu@xxxxxxx> > > Since we now have ntime_since() we can use nsec in the division for > get_cycles_per_msec(). This makes the cycles_per_msec value that fio > ultimately uses more stable since fio will no longer be using values > truncated to usec. > > While we're here also modify some debug prints to make it explicit that > fio ultimately uses a trimmed mean in its time calculations. > > On platforms where only gettimeofday() is available this will be no > worse than the original code since we will revert back to using times > truncated to usec. > > With the patch, the last three digits of the trimmed mean have a tight > range from 784-786. Without the patch, the corresponding value (labeled > avg) has a much wider range from 821-958. Notice also that the standard > error S is an order of magnitude smaller with the patch. This is great, thanks Vincent. Applied. -- Jens Axboe
