Re: [patch 3/3] memcg: never OOM when charging huge pages

From: KAMEZAWA Hiroyuki
Date: Thu Jan 27 2011 - 18:50:30 EST


On Thu, 27 Jan 2011 14:47:03 +0100
Johannes Weiner <hannes@xxxxxxxxxxx> wrote:

> Huge page coverage should obviously have less priority than the
> continued execution of a process.
>
> Never kill a process when charging it a huge page fails. Instead,
> give up after the first failed reclaim attempt and fall back to
> regular pages.
>
> Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>

Ah, I missed this. I'll merge this patch into my series.
Thank you for pointing out.

But what I have to point out here is khugepaged lock-up issue needs
another fix for khugepaged itself. It should skip hopeless memcg.
I think I can send patches, today.

Thanks,
-Kame


> ---
> mm/memcontrol.c | 7 +++++++
> 1 files changed, 7 insertions(+), 0 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 17c4e36..2945649 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -1890,6 +1890,13 @@ static int __mem_cgroup_try_charge(struct mm_struct *mm,
> int csize = max(CHARGE_SIZE, (unsigned long) page_size);
>
> /*
> + * Do not OOM on huge pages. Fall back to regular pages after
> + * the first failed reclaim attempt.
> + */
> + if (page_size > PAGE_SIZE)
> + oom = false;
> +
> + /*
> * Unlike gloval-vm's OOM-kill, we're not in memory shortage
> * in system level. So, allow to go ahead dying process in addition to
> * MEMDIE process.
> --
> 1.7.3.5
>
> --
> 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/
>

--
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/