Messages in this thread | | | Date | Sun, 27 Dec 2009 22:22:20 -0500 | From | Rik van Riel <> | Subject | Re: [PATCH -mmotm-2009-12-10-17-19] Prevent churning of zero page in LRU list. |
| |
On 12/27/2009 09:53 PM, Minchan Kim wrote: > > VM doesn't add zero page to LRU list. > It means zero page's churning in LRU list is pointless. > > As a matter of fact, zero page can't be promoted by mark_page_accessed > since it doesn't have PG_lru. > > This patch prevent unecessary mark_page_accessed call of zero page > alghouth caller want FOLL_TOUCH. > > Signed-off-by: Minchan Kim<minchan.kim@gmail.com>
The code looks correct, but I wonder how frequently we run into the zero page in this code, vs. how much the added cost is of having this extra code in follow_page.
What kind of problem were you running into that motivated you to write this patch?
-- All rights reversed.
| |