On Mon, Jan 29, 2024 at 04:32:03AM +0000, Matthew Wilcox wrote: > Our documentation of the current page flags is ... not great. I think > I can improve it for the page cache side of things; I understand the > meanings of locked, writeback, uptodate, dirty, head, waiters, slab, > mlocked, mappedtodisk, error, hwpoison, readahead, anon_exclusive, > has_hwpoisoned, hugetlb and large_remappable. > > Where I'm a lot more shaky is the meaning of the more "real MM" flags, > like active, referenced, lru, workingset, reserved, reclaim, swapbacked, > unevictable, young, idle, swapcache, isolated, and reported. > > Perhaps we could have an MM session where we try to explain slowly and > carefully to each other what all these flags actually mean, talk about > what combinations of them make sense, how we might eliminate some of > them to make more space in the flags word, and what all this looks like > in a memdesc world. > > And maybe we can get some documentation written about it! Not trying > to nerd snipe Jon into attending this session, but if he did ... I suspect Jon will be there anyway, but not sure he'd be willing to do the writing :) I was going to propose the "mm docs" session again, but this one seems more useful than talking yet again about how hard it is to get MM documentation done. And I can take on myself putting the explanations from this session into writing. > [thanks to Amir for reminding me that I meant to propose this topic] > -- Sincerely yours, Mike.
