Re: page fault scalability patch V11 [0/7]: overview

Robin Holt
2004-11-20T02:06:15Z

On Fri, Nov 19, 2004 at 11:42:39AM -0800, Christoph Lameter wrote:
> Note that I have posted two other approaches of dealing with the rss problem:
>
> A. make_rss_atomic. The earlier releases contained that patch but then another
> variable (such as anon_rss) was introduced that would have required additional
> atomic operations. Atomic rss operations are also causing slowdowns on
> machines with a high number of cpus due to memory contention.
>
> B. remove_rss. Replace rss with a periodic scan over the vm to determine
> rss and additional numbers. This was also discussed on linux-mm and linux-ia64.
> The scans while displaying /proc data were undesirable.

Can you run a comparison benchmark between atomic rss and anon_rss and
the sloppy rss with the rss and anon_rss in seperate cachelines. I am not
sure that it is important to seperate the two into seperate lines, just
rss and anon_rss from the lock and sema.

If I have the time over the weekend, I might try this myself. If not, can
you give it a try.

Thanks,
Robin