perl -MTime::HiRes=gettimeofday,tv_interval -e '$istart=1000;$iend=5000; $t0=[gettimeofday]; for $x($istart..$iend){for $y($istart..$iend){ $x/$y }}; $t1=[gettimeofday]; print "lasted->".tv_interval($t0,$t1)."\n"'