Messages in this thread | | | Date | Tue, 9 Aug 2022 14:25:05 -0700 | From | Roman Gushchin <> | Subject | Re: [PATCH 0/3] enable memcg accounting for kernfs objects |
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On Tue, Aug 09, 2022 at 07:31:31AM -1000, Tejun Heo wrote: > (cc'ing Johannes) > > Hello, > > On Sun, Jul 31, 2022 at 06:37:15PM +0300, Vasily Averin wrote: > > 1) creating a new netdevice allocates ~50Kb of memory, where ~10Kb > > was allocated for 80+ kernfs nodes. > > > > 2) cgroupv2 mkdir allocates ~60Kb of memory, ~10Kb of them are kernfs > > structures. > > > > 3) Shakeel Butt reports that Google has workloads which create 100s > > of subcontainers and they have observed high system overhead > > without memcg accounting of kernfs. > > So, I don't have anything against accounting kernfs objects in general but, > for cgroups, because cgroups are what determines what gets charged where, > I'm not quite sure whether following the usual "charge it to the allocating > task's cgroup" is the best way to go about it. I wonder whether it'd be > better to attach it to the new cgroup's nearest ancestor with memcg enabled.
I also like this approach better, however Michal had some arguments against it. I don't think there is a huge practical difference, so I'm ok with either approach.
Thanks!
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