KEP-4786: direct cgroup status collection on Node

[linxiulei]

• One-line PR description: Direct cgroup stats collection on Node

• Issue link: Direct cgroup stats collection #4786

• Other comments:

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[kannon92]

/retitle KEP-4786: direct cgroup status collection on Node

[kannon92]

Image filesystem also.

[linxiulei]

Pls correct me if I'm wrong. I think imagefs is taken care of by CRI, no?

[kannon92]

It is not.

[linxiulei]

did you refer to https://github.com/kubernetes/kubernetes/blob/master/pkg/kubelet/stats/cri_stats_provider.go#L389 called by https://github.com/kubernetes/kubernetes/blob/master/pkg/kubelet/server/stats/summary.go#L85?

[kannon92]

Looking at that code, we are using cadvisor for Availability and Capacity.

[linxiulei]

Yes, but that cadvisor will be replaced to not use cadvisor

[iholder101]

So, IIUC, KEP-2371 is about implementing the missing bits from the CRI/CRI-API perspective and this KEP would actually remove the use of cadvisor wherever it's necessary?

[linxiulei]

Yes, but not entirely removing the use of cadvisor. More specifically, this KEP will remove the background task that runs cadvisor routines but still call cadvisor code on demand.