Re: [PATCH V2 0/5] memcg softlimit reclaim rework

[Ying Han <yinghan@google.com>]

On Sat, Apr 14, 2012 at 5:19 AM, Hillf Danton <dhillf@gmail.com> wrote:
> On Thu, Apr 12, 2012 at 5:56 AM, Ying Han <yinghan@google.com> wrote:
>> The "soft_limit" was introduced in memcg to support over-committing the
>> memory resource on the host. Each cgroup configures its "hard_limit" where
>> it will be throttled or OOM killed by going over the limit. However, the
>> cgroup can go above the "soft_limit" as long as there is no system-wide
>> memory contention. So, the "soft_limit" is the kernel mechanism for
>> re-distributng system spare memory among cgroups.
>>
> s/re-distributng/re-distributing/
>
>> This patch reworks the softlimit reclaim by hooking it into the new global
>> reclaim scheme. So the global reclaim path including direct reclaim and
>> background reclaim will respect the memcg softlimit.
>>
>> Note:
>> 1. the new implementation of softlimit reclaim is rather simple and first
>> step for further optimizations. there is no memory pressure balancing between
>> memcgs for each zone, and that is something we would like to add as follow-ups.
>>
>> 2. this patch is slightly different from the last one posted from Johannes,
>>
> For those who want to see posts by Johannes, add links please.

http://comments.gmane.org/gmane.linux.kernel.mm/72382

If that is helpful, i will include it into the next post.

--Ying

>
>> where his patch is closer to the reverted implementation by doing hierarchical
>> reclaim for each selected memcg. However, that is not expected behavior from
>> user perspective. Considering the following example:
>>

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>