3 ms·
How is this possible? Is it that Windows 11 is constantly running code and/or using data so that it consumes more of the L3 cache all the time? But only on AMD?
by jerf 5y ago
How is this possible? Is it that Windows 11 is constantly running code and/or using data so that it consumes more of the L3 cache all the time? But only on AMD? Is this really a linear slowdown of cache speed as the article's wording implies, or is it some more complicated slowdown that they've benchmarked with something that intrinsically measures it linearly?
Problems with the thread migration to certain classes of CPUs I can kind of understand, that's still fairly new code for windows, but how it can slow down the L3 cache in the described way is a bit of a mystery to me.
- h2odragon 5y agoTotally ignorant guess: sounds like they're invalidating too much sometimes, like having one core clear all the shared cache instead of just the lines it stepped on or something. There's big hairy problems down in the tiny little details there that are easy to have come out and eat you.
- deleted 5y ago[deleted]
- deleted 5y ago[deleted]
- TillE 5y agoThis is the actual interesting question here. A simple constant slowdown seems physically impossible, and explanations which apply equally to Intel CPUs can presumably be discarded. So I would guess, as the previous reply does, that it's probably somehow linked to the threading issue.