Re: MM patches (was Re: why swap at all?)

[Con Kolivas <kernel@kolivas.org>]

On Mon, 31 May 2004 23:13, Tvrtko A. Uršulin wrote:
> On Saturday 29 May 2004 10:40, Nick Piggin wrote:
> > It is a cocktail of cleanups, simplification, and enhancements. The
> > main ones that applie here is my split active lists patch (search
> > archives for details), and explicit use-once logic.
>
> I didn't have time to personally test it but just want to share some
> thoughts. This kind of improvement is absolutely necessary for 2.6 to be
> usefull on the desktop. It continues to escape me how come that this kind
> of, almost, bugfix arrives so late during stable period.
>
> Unfortunately it doesn't apply on top of Con's autoregulate swappines (AM
> from now on) which I am currently testing. AM also does an excellent job in
> preventing swap trashing while doing a lot of filesystem reading.
>
> I am curious on how does your patch technically relates to Con's AM, and is
> it possible to merge the two? I know that they do their job on completely
> different ways, so the real question would be: Is there a need for
> something like AM if using your patch, or it completely obsoletes it?

I had a quick look at Nick's patches to see for you and it appears that Nick's 
work completely removes the swappiness dial and introduces a different metric 
called vm_mapped_page_cost which is not interchangeable with the swappiness 
value. ie they cannot work together, sorry.

Con