var func = function(x) {
return x*x;
}
var x = [];
var y = [];
for (var i=0; i < 1000; i++) {
var s_time = performance.now()
for (var j=0; j < 1; j++) {
func(Math.random())
}
var dur = (performance.now()-s_time)
x.push(i+1)
y.push(dur)
}