Re: [RFC][PATCH 0/5] Memory controller soft limit patches (v9)

Balbir Singh
2009-07-20T15:48:58Z

* Balbir Singh <balbir@linux.vnet.ibm.com> [2009-07-10 18:29:50]:

>
> From: Balbir Singh <balbir@linux.vnet.ibm.com>
>
> New Feature: Soft limits for memory resource controller.
>
> Here is v9 of the new soft limit implementation. Soft limits is a new feature
> for the memory resource controller, something similar has existed in the
> group scheduler in the form of shares. The CPU controllers interpretation
> of shares is very different though.
>
> Soft limits are the most useful feature to have for environments where
> the administrator wants to overcommit the system, such that only on memory
> contention do the limits become active. The current soft limits implementation
> provides a soft_limit_in_bytes interface for the memory controller and not
> for memory+swap controller. The implementation maintains an RB-Tree of groups
> that exceed their soft limit and starts reclaiming from the group that
> exceeds this limit by the maximum amount.
>
> v9 attempts to address several review comments for v8 by Kamezawa, including
> moving over to an event based approach for soft limit rb tree management,
> simplification of data structure names and many others. Comments not
> addressed have been answered via email or I've added comments in the code.
>
> TODOs
>
> 1. The current implementation maintains the delta from the soft limit
> and pushes back groups to their soft limits, a ratio of delta/soft_limit
> might be more useful
>

Hi, Andrew,

Could you please pick up this patchset for testing in -mm, both
Kamezawa-San and Kosaki-San have looked at the patches. I think they
are ready for testing in mmotm.