4 ms·

Yes, in Linus's case, it is a faster overall runtime, but such a stark difference in cycle times is a bit of an eyebrow raiser. Caching is supposed to speed th

Yes, in Linus's case, it is a faster overall runtime, but such a stark difference in cycle times is a bit of an eyebrow raiser. Caching is supposed to speed things up, so it is kinda silly that the caching system has somehow gone backwards in overall performance. Pagefaults are a critical path for performance concerns in almost any software system that needs high-performance. If they are 10% slower, then its like the worst case performance of the computer is 10% slower. Anyone who needs to write high performance code (say, simulations, or game design: http://gameprogrammingpatterns.com/data-locality.html http://gameprogrammingpatterns.com/data-locality.html ), is concerned with avoiding pagefaults and cache misses, but the average code (general case?) doesn't concern itself with this as much, so the average program may end up experiencing this more than a linux compile.

acqq 12y ago
Try to count the total number of page faults per second in any task you're doing. I don't know of any "average code" that produces an order of 3 millions PF per second, which is needed for you to observe 10% slowdown. The code which does that doesn't do anything than doing the page faults. Linus claims he managed to get 5% slowdown when doing nothing but PF. It's probably something like hundreds of thousands per second at most, giving you something like a less than 0.5% slowdown. Versus the speedup of 300% for some other code (it's an extreme value actually, but still). Your newer Intel CPU certainly didn't get slower on average code compared to the Core Duo, for the same clock speed. Nothing to raise the eyebrows here. I believe it's not "in Linus case" but "in every case" that the overall time is shorter.