Re: [RFC][PATCH 1/5] memcg: change for softlimit.

KAMEZAWA Hiroyuki
2009-08-28T15:06:27Z

Balbir Singh wrote:
> * KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> [2009-08-28
> 23:40:56]:
>
>> KAMEZAWA Hiroyuki wrote:
>> > Balbir Singh wrote:
>> >> But Bob and Mike might need to set soft limits between themselves. if
>> >> soft limit of gold is 1G and bob needs to be close to 750M and mike
>> >> 250M, how do we do it without supporting what we have today?
>> >>
>> > Don't use hierarchy or don't use softlimit.
>> > (I never think fine-grain soft limit can be useful.)
>> >
>> > Anyway, I have to modify unnecessary hacks for res_counter of
>> softlimit.
>> > plz allow modification. that's bad.
>> > I postpone RB-tree breakage problem, plz explain it or fix it by
>> yourself.
>> >
>> I changed my mind....per-zone RB-tree is also broken ;)
>>
>> Why I don't like broken system is a function which a user can't
>> know/calculate how-it-works is of no use in mission critical systems.
>>
>> I'd like to think how-to-fix it with better algorithm. Maybe RB-tree
>> is not a choice.
>>
>
> Soft limits are not meant for mission critical work :-) Soft limits is
> best effort and not a guaranteed resource allocation mechanism. I've
> mentioned in previous emails how we recover if we find the data is
> stale
>
yes. but can you explain how selection will be done to users ?
I can't.

Thanks,
-Kame