Re: [PATCH] mm: avoid the unnecessary waiting when force empty a cgroup

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue 03-04-18 15:12:09, Li RongQing wrote:
> The number of writeback and dirty page can be read out from memcg,
> the unnecessary waiting can be avoided by these counts

This changelog doesn't explain the problem and how the patch fixes it.
Why do wee another throttling when we do already throttle in the reclaim
path?

> Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx>
> ---
>  mm/memcontrol.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 9ec024b862ac..5258651bd4ec 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -2613,9 +2613,13 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg)
>  		progress = try_to_free_mem_cgroup_pages(memcg, 1,
>  							GFP_KERNEL, true);
>  		if (!progress) {
> +			unsigned long num;
> +
> +			num = memcg_page_state(memcg, NR_WRITEBACK) +
> +					memcg_page_state(memcg, NR_FILE_DIRTY);
>  			nr_retries--;
> -			/* maybe some writeback is necessary */
> -			congestion_wait(BLK_RW_ASYNC, HZ/10);
> +			if (num)
> +				congestion_wait(BLK_RW_ASYNC, HZ/10);
>  		}
>  
>  	}
> -- 
> 2.11.0

-- 
Michal Hocko
SUSE Labs




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux