Re: Fairness in love and swapping

[Rik van Riel <H.H.vanRiel@fys.ruu.nl>]

On Mon, 2 Mar 1998, Stephen C. Tweedie wrote:

> a) the kernel likes to keep reclaiming pages from a single source if
> it is finding it easy to locate unused pages there, so when it starts
> on the page cache it _can_ get over zealous in reaping those pages;
> and

Correction: It _will_ get over zealous in reaping those pages.

> b) starting to find free pages from swap is inherently difficult due
> to the initial age placed on pages.
> 
> I rather suspect with those patches that it's not simply the aging of
> page cache pages which helps performance, but also the tuning of the
> balance between page cache and data page reclamation.

That's why I proposed the true LRU aging on those pages,
so they get a better chance of (re)usal before they're
really freed and forgotten about (and need to be reread
in the case of readahead pages).

I might be working on this RSN.

Rik.
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