Re: broken VM in 2.4.10-pre9

Jeremy Zawodny
2001-09-16T17:30:34Z

On Sun, Sep 16, 2001 at 07:06:45PM +0200, Ricardo Galli wrote:
> On Sun, 16 Sep 2001, Rik van Riel wrote:
> >
> > > Is there a way to tell the VM to prune its cache? Or a way to limit
> > > the amount of cache it uses?
> >
> > Not yet, I'll make a quick hack for this when I get back next
> > week. It's pretty obvious now that the 2.4 kernel cannot get
> > enough information to select the right pages to evict from
> > memory.
>
> ....
>
> On Sun, 16 Sep 2001, Jeremy Zawodny wrote:
> >
> > Agreed. I'd be great if there was an option to say "Don't swap out
> > memory that was allocated by these programs. If you run out of disk
> > buffers, toss the oldest ones and start re-using them."
>
> More easy though (for cases of listening mp3's and backups): cache
> pages that were accesed only "once"(*) several seconds ago must be
> discarded first. It only implies a check against an access counter
> and a "last accesed" epoch fields of the page.

Yeah, something along those lines would be great. It would keep a big
(13 GB) drive to drive file copy from causing a large (400MB) and
relatively active process from having its memory swapped out (and then
back in 20 seconds later).

Imagine watching that for 45 minutes while a backup that used to take
5-8 minutes runs.

Jeremy
--
Jeremy D. Zawodny | Perl, Web, MySQL, Linux Magazine, Yahoo!
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