Re: 2.4.19pre1aa1

[Mike Fedyk <mfedyk@matchmail.com>]

On Thu, Feb 28, 2002 at 05:11:25PM -0500, Bill Davidsen wrote:
> On Wed, 27 Feb 2002, Andrea Arcangeli wrote:
> 
> > I would like to have feedback about this VM update, if nobody can find
> > any serious issue I'd try to push vm-28 into mainline during 2.4.19pre.
> > Please test oom conditions as well.
> 
> I have enjoyed using your -aa patches (and run child first) for some time,
> and Rik's rmap patches as well. However, I find that for some machines
> your stuff works clearly better, particularly larger memory machines, and
> for some rmap is clearly more responsive, particularly for small machines
> under heavy memory pressure.
> 
> The point is that choice is good, and having two solutions two address
> various machines is a good thing, even if the convenience isn't all that
> great. That being said, I fear that if your solution gets pushed into
> mainline that it will preempt other solutions. And my testing tells me
> that there is no one solution here, even with all the tuning in your VM,
> using the hints you gave me.
> 

The problem here is that currently the mainline kernel makes some bad
dicesions in the VM, and -aa is the solution in this case.  When -aa is
merged, you will still have both solutions; one in mainline, one as a patch
(rmap).

Linus has already changed the VM once in 2.4, and I don't really see another
large VM change (rmap in 2.4) happening again.

Rmap looks promising for a 2.5 merge after several issues are overcome
(pte-highmem, etc).

Mike