[Ksummit-2012-discuss] [ATTEND] writeback and kernel testing

[Fengguang Wu]

On Mon, Jun 18, 2012 at 02:57:52PM +0530, Balbir Singh wrote:
> On Sun, Jun 17, 2012 at 8:47 AM, Fengguang Wu <fengguang.wu at intel.com> wrote:
> > On Sun, Jun 17, 2012 at 08:03:15AM +0530, Balbir Singh wrote:
> >> On Sat, Jun 16, 2012 at 6:14 PM, Fengguang Wu <fengguang.wu at intel.com> wrote:
> >> > Greetings,
> >> >
> >> > I'd like to attend this year's kernel summit.
> >> >
> >> > I may talk about the technical challenges and trade-offs on writeback and memcg
> >> > and IO controllers with anyone interested, perhaps in some breakout session.
> >> >
> >>
> >> Do you have a reference for the tests you've mentioned. Do you have a
> >> brief summary of the challenges and trade-offs?
> >
> > - memcg with dirty limits
> >
> >  The basic agreements are, we'll do per-memcg dirty limit, but set the
> >  limits reasonably high and do not expose interfaces to user space.
> >
> 
> No interfaces in user-space, how is it expected to work via the global limits?

Yeah, we could implicitly tie the per-memcg dirty limits to the global one.
For example, do 40% memcg dirty ratio when the global ratio is 20%.

At the same time, we'll need to improve the page reclaim code so that
it works well even when a LRU list has 40% dirty pages. I believe this
is an achievable goal when we put dirty pages to a standalone LRU list. 

Thanks,
Fengguang