Re: [PATCH] swap_state.c thinko

Andrea Arcangeli
2001-04-06T19:09:08Z

On Fri, Apr 06, 2001 at 07:37:55PM +0100, Hugh Dickins wrote:
> swapper_space.nrpages, that's neat, but I insist it's not right.
> You're then double counting into "free" all the swap cache pages
> (already included in page_cache_size) which correspond to pages
> of swap for running processes - erring in the opposite direction
> to the present code.

The whole point is that errirng in the opposite direction is perfectly fine,
that's expected. Understimating is a bug instead. Period.

We always overstimate anyways, we have to because we don't have information
about the really freeable memory (think at the buffer cache pinned in the
superblock metadata of ext2, do you expect to be able to reclaim it somehow?).

Andrea