Re: page fault scalability patch V12 [0/7]: Overview and performance tests

From: Hugh Dickins
Date: Fri Dec 10 2004 - 19:46:58 EST


On Fri, 10 Dec 2004, Andrew Morton wrote:
> Hugh Dickins <hugh@xxxxxxxxxxx> wrote:
> > But why is do_anonymous_page adding anything to lru_cache_add_active,
> > when its other callers leave it at that? What's special about the
> > do_anonymous_page case?
>
> do_swap_page() is effectively doing the same as do_anonymous_page().
> do_wp_page() and do_no_page() appear to be errant.

Demur. do_swap_page has to mark_page_accessed because the page from
the swap cache is already on the LRU, and for who knows how long.
The others (and count in fs/exec.c's install_arg_page) are dealing
with a freshly allocated page they are putting onto the active LRU.

My inclination would be simply to remove the mark_page_accessed
from do_anonymous_page; but I have no numbers to back that hunch.

Hugh

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/