> Hey, this looks _really_ nice. I never liked the special-cases
> that you removed (drop_behind in particular), and I have to say
> that the new code looks a lot saner, even without your extensive
> description and timing analysis.
Fully agreed, drop_behind is an ugly hack. The sooner
it dies the happier I am ;)
> Please people, test this out extensively - I'd love to integrate
> it, but while it looks very sane I'd really like to hear of
> different peoples reactions to it under different loads.
The one thing which has always come up in LRU/k and 2Q
papers is that the "first reference" can really be a
series of references in a very short time.
Counting only the very first reference will fail if we
do eg. sequential IO with non-page aligned read() calls,
which doesn't look like it's too uncommon.
In order to prevent this from happening, either the system
counts all first references in a short timespan (complex to
implement) or it has the new pages on a special - small fixed
size - page list and all references to the page while on that
list are ignored.
regards,
Rik
-- Executive summary of a recent Microsoft press release: "we are concerned about the GNU General Public License (GPL)"
http://www.surriel.com/ http://www.conectiva.com/ http://distro.conectiva.com/
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/