Re: [RFC][PATCH 5/5] memcg: drain per cpu stock

From: KAMEZAWA Hiroyuki
Date: Mon Aug 31 2009 - 08:10:04 EST

Balbir Singh さんは書きました:
> * KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> [2009-08-28
> 13:28:09]:
>> Add function for dropping per-cpu stock of charges.
>> This is called when
>> - cpu is unplugged.
>> - force_empty
>> - recalim seems to be not easy.
>> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
> The complexity of this patch and additional code make percpu_counter
> more attractive. Why not work on percpu_counter if that is not as good
> as we expect it to be and in turn help other exploiters as well.

- percpu counter is slow.
- percpu counter is "counter". we use res_counter not as counter but as
accounting for "limit". This "borrow" charges is core of this patch.
- Adding "flush" ops for percpu counter will be much more mess.
- This implementation handles mem->res and mem->memsw at the same time.
This reduces much overhead.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at