Re: [patch 5/8] mm: vmscan: improve comment on low-page cachehandling
From: Michal Hocko
Date:  Thu Dec 13 2012 - 11:07:32 EST
On Wed 12-12-12 16:43:37, Johannes Weiner wrote:
> Fix comment style and elaborate on why anonymous memory is
> force-scanned when file cache runs low.
> 
> Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
yes, much better
Reviewed-by: Michal Hocko <mhocko@xxxxxxx>
> ---
>  mm/vmscan.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 5e1beed..05475e1 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -1697,13 +1697,15 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
>  	file  = get_lru_size(lruvec, LRU_ACTIVE_FILE) +
>  		get_lru_size(lruvec, LRU_INACTIVE_FILE);
>  
> +	/*
> +	 * If it's foreseeable that reclaiming the file cache won't be
> +	 * enough to get the zone back into a desirable shape, we have
> +	 * to swap.  Better start now and leave the - probably heavily
> +	 * thrashing - remaining file pages alone.
> +	 */
>  	if (global_reclaim(sc)) {
> -		free  = zone_page_state(zone, NR_FREE_PAGES);
> +		free = zone_page_state(zone, NR_FREE_PAGES);
>  		if (unlikely(file + free <= high_wmark_pages(zone))) {
> -			/*
> -			 * If we have very few page cache pages, force-scan
> -			 * anon pages.
> -			 */
>  			fraction[0] = 1;
>  			fraction[1] = 0;
>  			denominator = 1;
> -- 
> 1.7.11.7
> 
-- 
Michal Hocko
SUSE Labs
--
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/