Re: clarification about misc controller and capacity vs. max

["Accardi, Kristen C" <kristen.c.accardi-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>]

On Tue, 2022-11-01 at 07:05 -1000, tj@kernel.org wrote:
> On Tue, Nov 01, 2022 at 05:03:25PM +0000, Accardi, Kristen C wrote:
> > So to be clear, if I have this:
> > 
> > /sys/fs/cgroup/misc.capacity
> > some_res 10
> > 
> > and this:
> > /sys/fs/cgroup/test
> > 
> > test.current will never be allowed to exceed 10.
> 
> Yes, but test.max can be whatever. So, the resources themselves can't
> be
> over-committed. The max limits (ie. the promises) can be.
> 
> Thanks.
> 

This is a bit of a deal breaker for the use of the misc controller for
SGX EPC memory - we allow overcommit of the physical EPC memory as we
have backing RAM that is used to swap. Would you be amenable to having
a flag to ignore the total capacity value and allow for overcommit of
the resource? If not I feel like we don't have a choice but to create a
new controller.