[sebilasse]

Generally agree with you (benchmarking isn't what it used to be ;-).

However the following examples all do nothing (except increasing i) and get different results.

http://jsperf.com/codethatdoesnothing/2 http://jsperf.com/functionwithwhilethatdoesnothing

[jcampbell1]

They don't increase i at all. It is impossible to count to 10,000 at a rate of 200Mhz. That implies a 2000Ghz processor.

JS Perf is fundamentally broken. It doesn't force a side effect, and from the debugger, the first step it does is something like:

    while(100,000,000--) {
      // your code here
    }

The chrome compiler then recognizes the loops can be swapped, and eliminated, thus it runs your code once, yet jsperf thinks it ran it hundreds of millions of times.