"Isn't this 'definitive experiment' just showing that code which doesn't take advantage of locality of reference is bound to be really slow if it is larger than the cache size? I mean, he's just executing trivial code from random locations in memory - not a typical access pattern at all. Because of this, the experiment exaggerates the effect of code size on performance. For example, if you had a 1 million line program that didn't loop, it's performance would not degrade nearly as much as his results imply." - Ajay Kapal