Re: [PATCH] swapin readahead

Rik van Riel
1998-12-01T16:24:57Z

On Tue, 1 Dec 1998, Stephen C. Tweedie wrote:
> In article <Pine.LNX.3.96.981127001214.445A-100000@mirkwood.dummy.home>,
> Rik van Riel <H.H.vanRiel@phys.uu.nl> writes:
>
> > here is a very first primitive version of as swapin

I am at version 3 now (4 in a few minutes?) but your
message still seems needed...

> > The checks are all needed. The first two checks are there
> > to avoid annoying messages from swap_state.c :))
>
> There's a third check needed, I think, which probably accounts for the
> swap_duplicate errors people have been noting. You need to skip pages
> which are marked as locked in the swap_lockmap, or the async page read
> may block

OK, I'll add this test and try again.

I also noted something else -- when I free a lot of memory
(80+ MB gimp picture) the system swaps itself to death.
Could that also be because of issues with locked/unlocked
swap_cache pages which in some magical way duplicate themselves
and fill up memory? I have seen 600+ MB of shared memory :(

cheers,

Rik -- now completely used to dvorak kbd layout...
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