Messages in this thread | | | Subject | Re: [ckrm-tech] [PATCH] BC: resource beancounters (v4) (added user memory) | From | Chandra Seetharaman <> | Date | Mon, 11 Sep 2006 12:42:05 -0700 |
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On Mon, 2006-09-11 at 12:10 -0700, Rohit Seth wrote: > On Mon, 2006-09-11 at 11:25 -0700, Chandra Seetharaman wrote: > > On Fri, 2006-09-08 at 14:43 -0700, Rohit Seth wrote: > > <snip> > > > > > > > Guarantee may be one of > > > > > > > > > > 1. container will be able to touch that number of pages > > > > > 2. container will be able to sys_mmap() that number of pages > > > > > 3. container will not be killed unless it touches that number of pages > > > > > 4. anything else > > > > > > > > I would say (1) with slight modification > > > > "container will be able to touch _at least_ that number of pages" > > > > > > > > > > Does this scheme support running of tasks outside of containers on the > > > same platform where you have tasks running inside containers. If so > > > then how will you ensure processes running out side any container will > > > not leave less than the total guaranteed memory to different containers. > > > > > > > There could be a default container which doesn't have any guarantee or > > limit. > > First, I think it is critical that we allow processes to run outside of > any container (unless we know for sure that the penalty of running a > process inside a container is very very minimal).
When I meant a default container I meant a default "resource group". In case of container that would be the default environment. I do not see any additional overhead associated with it, it is only associated with how resource are allocated/accounted.
> > And anything running outside a container should be limited by default > Linux settings.
note that the resource available to the default RG will be (total system resource - allocated to RGs). > > > When you create containers and assign guarantees to each of them > > make sure that you leave some amount of resource unassigned. > ^^^^^ This will force the "default" container > with limits (indirectly). IMO, the whole guarantee feature gets defeated
You _will_ have limits for the default RG even if we don't have guarantees.
> the moment you bring in this fuzziness.
Not really. - Each RG will have a guarantee and limit of each resource. - default RG will have (system resource - sum of guarantees) - Every RG will be guaranteed some amount of resource to provide QoS - Every RG will be limited at "limit" to prevent DoS attacks. - Whoever doesn't care either of those set them to don't care values.
> > > That > > unassigned resources can be used by the default container or can be used > > by containers that want more than their guarantee (and less than their > > limit). This is how CKRM/RG handles this issue. > > > > > > It seems that a single notion of limit should suffice, and that limit > should more be treated as something beyond which that resource > consumption in the container will be throttled/not_allowed.
As I stated in an earlier email "Limit only" approach can prevent a system from DoS attacks (and also fits the container model nicely), whereas to provide QoS one would need guarantee.
Without guarantee, a RG that the admin cares about can starve if all/most of the other RGs consume upto their limits.
> > -rohit > > > ------------------------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > ckrm-tech mailing list > https://lists.sourceforge.net/lists/listinfo/ckrm-tech --
---------------------------------------------------------------------- Chandra Seetharaman | Be careful what you choose.... - sekharan@us.ibm.com | .......you may get it. ----------------------------------------------------------------------
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