[Devel] Re: [ckrm-tech] [PATCH] BC: resource beancounters (v4) (added user memory)

[Rohit Seth]

On Wed, 2006-09-13 at 15:20 -0700, Chandra Seetharaman wrote:
> On Tue, 2006-09-12 at 18:25 -0700, Rohit Seth wrote:
> > On Tue, 2006-09-12 at 18:10 -0700, Chandra Seetharaman wrote:
> > > On Tue, 2006-09-12 at 17:39 -0700, Rohit Seth wrote:
> > > <snip>
> > > > > yes, it would be there, but is not heavy, IMO.
> > > > 
> > > > I think anything greater than 1% could be a concern for people who are
> > > > not very interested in containers but would be forced to live with them.
> > > 
> > > If they are not interested in resource management and/or containers, i
> > > do not think they need to pay.
> > > > 
> > 
> > Think of a single kernel from a vendor that has container support built
> > in.
> 
> Ok. Understood.
> 
> Here are results of some of the benchmarks we have run in the past
> (April 2005) with CKRM which showed no/negligible performance impact in
> that scenario.
> http://marc.theaimsgroup.com/?l=ckrm-tech&m=111325064322305&w=2
> http://marc.theaimsgroup.com/?l=ckrm-tech&m=111385973226267&w=2
> http://marc.theaimsgroup.com/?l=ckrm-tech&m=111291409731929&w=2
> > 


These are good results.  But I still think the cost will increase over a
period of time as more logic gets added.  Any data on microbenchmarks
like lmbench.
 
> <snip>
> 
> > > Not at all. If the container they are interested in is guaranteed, I do
> > > not see how apps running outside a container would affect them.
> > > 
> > 
> > Because the kernel (outside the container subsystem) doesn't know of
> 
> The core resource subsystem (VM subsystem for memory) would know about
> the guarantees and don't cares, and it would handle it appropriately.
> 

...meaning hooks in the generic kernel reclaim algorithm.  Getting
something like that in mainline will be at best tricky.


-rohit