OpenImageIO/oiio — pull request #743 by lgritz (2013-11-17 18:35:41+00:00)
Title: Speed up timer on OSX and Windows by precomputing seconds_per_tick.

Testing on my OSX laptop, this sped up timer begin/end from 5.2 M/sec
to 28 M/s, i.e. reduces the overhead of using timers by 80%.