Re: [patch] vmfixes-2.4.0-test9-B2 - fixing deadlocks

Rik van Riel
2000-09-29T15:40:14Z

On Fri, 29 Sep 2000, Andrea Arcangeli wrote:
> On Fri, Sep 29, 2000 at 11:39:18AM -0300, Rik van Riel wrote:
> > OK, good to see that we agree on the fact that we
> > should age and swapout all pages equally agressively.
>
> Actually I think we should start looking at the mapped stuff
> _only_ when the I/O cache aging is relevant. If the I/O cache
> aging isn't relevant there's no point to look at the mapped
> stuff since there's cache pollution going on.

> If the cache is re-used (so if it's useful) that's completly
> different issue and in that case unmapping potentially unused
> stuff is the right thing to do of course.

This is why I want to do:

1) equal aging of all pages in the system
2) page aging to have properties of both LRU and LFU
3) drop-behind to cope with streaming IO in a good way

and maybe:
4) move unmapped pages to the inactive_clean list for
immediate reclaiming but put pages which are/were
mapped on the inactive_dirty list so we keep it a
little bit longer

The only way to reliably know if the cache is re-used a
lot is by making sure we do the page aging for unmapped
and mapped pages the same. If we don't do that, we won't
be able to make a sensible comparison between the activity
of pages in different places.

regards,

Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000

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