what is pagecache page

Question

/* * Each physical page in the system has a struct page associated with * it to keep track of whatever it is we are using the page for at the * moment. Note that we have no way to track which tasks are using * a page, though if it is a pagecache page, rmap structures can tell us * who is mapping it. */

include/linux/mm_types.h

Here Please lemme know what is "pagecache page" means?

Thanks!

Answer 1

The pagecache is - as the name suggests - a cache of physical pages.

http://www.moses.uklinux.net/patches/lki-4.html

It is used to store filesystem cache (disk cache).

Mmaped files seems to use pagecache too.

And the "pagecache page" means page, which belongs to pagecache