On Tue, 2022-11-01 at 06:54 -1000, tj@xxxxxxxxxx wrote: > Hello, > > On Tue, Nov 01, 2022 at 04:40:22PM +0000, Accardi, Kristen C wrote: > > I notice in the comments for the misc controller it is stated that > > the > > max limit can be more than actual total capacity, meaning that we > > can > > overcommit with the resource controlled by the misc controller. > > However, in the misc_cg_try_charge() code, the function will return > > - > > EBUSY if max limit will be crossed or total usage will be more than > > the > > capacity, which would seem to enforce total capacity as an upper > > limit > > in addition to max and not allow for overcommit. Can you provide > > some > > clarity on whether the resource consumption model for the misc > > controller should allow for overcommit? > > I think what it's trying to say is that the sum of first level .max's > can be > higher than the total capacity. e.g. Let's say you have 5 of this > resource > and a hierarchy like the following. > > R - A - A' > + B - B' > \ C > > It's valid to have A, B, C's max set to 4, 3, 2 respectively even if > they > sum up to 9 which is larger than what's available in the system, 5 - > ie. the > max limits are overcommitted for the resource. > > Thanks. > 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.
