Very cool. I've actually been trying to learn about this area recently. I know this was aside from the main thrust of the article, but this but made me think:
Page Cache Disabled (PCD) – pages descendant of this PGD entry should not enter the CPU’s cache hierarchy, sometimes also called the ‘Uncacheable’ (UC) bit.
I guess this is some optimisation where it's decided the page isn't worth taking up valuble CPU cache state. And now I'm wondering what this algorithm is that decides it..
Page Cache Disabled (PCD) – pages descendant of this PGD entry should not enter the CPU’s cache hierarchy, sometimes also called the ‘Uncacheable’ (UC) bit.
I guess this is some optimisation where it's decided the page isn't worth taking up valuble CPU cache state. And now I'm wondering what this algorithm is that decides it..