Who said me slow ?
http://www.dragonflybsd.org/docs/nanosleep/wakeup_lat_by_os.png
The above graph is taken from an article on how long nanosleep(2) actually sleeps. The linked article discusses the skew caused by aliasing, which effected Free and DragonFly BSDs, but I am particularly interested in the Darwin and Linux plots when compared to the Solaris plot.