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Berrange" , Alex Williamson , Zefan Li , Andrew Morton Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: D63CC80011 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: 7opc6br6ip6cexhj1rpoipyyzfddea5h X-HE-Tag: 1675723195-927642 X-HE-Meta: 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 vH21qhxm f3r9Cn6LRaAMDLtZxsO1BGkpy9H9i0JeDdIA9JQb8sETaIK6peKzztUmEOJM76Y+tw+ao13+aEtJ8Nr0SY5WSor0jmT58yUZqgLx8wY37Yt7vUHGinMUpMBPxljBZZZmr81gTnE505u9FKoai4ZNB2D+E7iDZiUjhjR5/tgeJWduGj5VvDNyeXMkcbwG+/kElmORBq9yHWb/dv7A1H7ZorK2AfGHZXU397V/nirO+q6l+jyISxHhTZ2dbXcpMbIKdDgzIKmmNdY2eyes= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Feb 6, 2023 at 2:36 PM Tejun Heo wrote: > > On Mon, Feb 06, 2023 at 02:32:10PM -0800, Yosry Ahmed wrote: > > I guess it boils down to which we want: > > (a) Limit the amount of memory processes in a cgroup can be pinned/locked. > > (b) Limit the amount of memory charged to a cgroup that can be pinned/locked. > > > > The proposal is doing (a), I suppose if this was part of memcg it > > would be (b), right? > > > > I am not saying it should be one or the other, I am just making sure > > my understanding is clear. > > I don't quite understand what the distinction would mean in practice. It's > just odd to put locked memory in a separate controller from interface POV. Assume we have 2 cgroups, A and B. A process in cgroup A creates a tmpfs file and writes to it, so the memory is now charged to cgroup A. Now imagine a process in cgroup B tries to lock this memory. - With (a) the amount of locked memory will count toward's cgroup A's limit, because cgroup A is charged for the memory. - With (b) the amount of locked memory will count toward's cgroup B's limit, because a process in cgroup B is locking the memory. I agree that it is confusing from an interface POV. > > Thanks. > > -- > tejun