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

[Rohit Seth]

On Fri, 2006-09-08 at 13:26 -0400, Shailabh Nagar wrote:

> Also maintenability, licensing, blah, blah.
> Replicating the software stack for each service level one
> wishes to provide, if avoidable as it seems to be, isn't such a good idea.
> Same sort of reasoning for why containers make sense compared to Xen/VMWare
> instances.
> 

Having a container per service level seems like an okay thing to me.

> Memory resources, by their very nature, will be tougher to account when a
> single database/app server services multiple clients and we can essentially
> give up on that (taking the approach that only limited recharging can ever
> be achieved). 

What exactly you mean by limited recharging?  

As said earlier, if there is big shared segment on a server then that
can be charged to any single container.  And in this case moving a task
to different container may not fetch anything useful from memory
accounting pov.

> But cpu atleast is easy to charge correctly and since that will
> also indirectly influence the requests for memory & I/O, its useful to allow
> middleware to change the accounting base for a thread/task.
> 

That is not true.   It depends on IO size, memory foot print etc. etc.
You can move a task to different container, but it will not be cheap.

-rohit