Operation
In traditional 32-bit protected mode, x86 processors use a two-level page translation scheme, where the control register CR3 points to a single 4 KiB long page directory, which is divided into 1024 x 4 byte entries that point to 4 KiB long page tables, similarly consisting of 1024 x 4 byte entries pointing to 4 KiB long pages.
Enabling PSE (by setting bit 4, PSE, of the system register CR4) changes this scheme. The entries in the page directory have an additional flag, in bit 7, named PS (for Page Size). This flag was ignored without PSE, but now, the page directory entry with PS set to 1 does not point to a page table, but to a single large 4 MiB page. The page directory entry with PS set to 0 behaves as without PSE.
Read more about this topic: Page Size Extension
Famous quotes containing the word operation:
“An absolute can only be given in an intuition, while all the rest has to do with analysis. We call intuition here the sympathy by which one is transported into the interior of an object in order to coincide with what there is unique and consequently inexpressible in it. Analysis, on the contrary, is the operation which reduces the object to elements already known.”
—Henri Bergson (1859–1941)
“You may read any quantity of books, and you may almost as ignorant as you were at starting, if you don’t have, at the back of your minds, the change for words in definite images which can only be acquired through the operation of your observing faculties on the phenomena of nature.”
—Thomas Henry Huxley (1825–95)
“It is critical vision alone which can mitigate the unimpeded operation of the automatic.”
—Marshall McLuhan (1911–1980)