Re: [PATCH] vmscan: Stop kswapd waiting on congestion when the min watermark is not being met

Rik van Riel
2009-11-13T18:37:47Z

On 11/13/2009 01:15 PM, Mel Gorman wrote:
> If reclaim fails to make sufficient progress, the priority is raised.
> Once the priority is higher, kswapd starts waiting on congestion. However,
> if the zone is below the min watermark then kswapd needs to continue working
> without delay as there is a danger of an increased rate of GFP_ATOMIC
> allocation failure.
>
> This patch changes the conditions under which kswapd waits on
> congestion by only going to sleep if the min watermarks are being met.
>
>
> diff --git a/mm/vmstat.c b/mm/vmstat.c
> index 90b11e4..bc09547 100644
> --- a/mm/vmstat.c
> +++ b/mm/vmstat.c
> @@ -685,6 +685,7 @@ static const char * const vmstat_text[] = {
> "kswapd_inodesteal",
> "kswapd_slept_prematurely_fast",
> "kswapd_slept_prematurely_slow",
> + "kswapd_no_congestion_wait",
>
>
Perhaps better named "kswapd_skip_congestion_wait" ?

Other than that, the patch looks good to me.

Reviewed-by: Rik van Riel <riel@redhat.com>