Kubelet support for Split Image Filesystem

[kannon92]

Enhancement Description

• One-line enhancement description (can be used as a release note): Kubelet can support ImageFilesystem being separated between writeable and read-only layer

• Kubernetes Enhancement Proposal: https://github.com/kubernetes/enhancements/blob/master/keps/sig-node/4191-split-image-filesystem/README.md

• Discussion Link: Garbage Collection Working group.

• Primary contact (assignee): @kannon92

• Responsible SIGs: sig-node

• Enhancement target (which target equals to which milestone):

  • Alpha CRI and Kubelet Implementation release target (x.y): 1.29
  • Alpha Container Runtime Support: 1.30
  • Beta release target (x.y): 1.31
  • Stable release target (x.y):

• Alpha - CRI Updates

  • KEP (k/enhancements) update PR(s):
    • KEP-4191 Split Image Filesystem #4198
  • Code (k/k) update PR(s):
    • Kubelet disk api cri update kubernetes#120914
    • Kubelet disk api changes kubernetes#120616

• Beta - container runtime support and ecosystem

  • Code (crio/crio):

    • update the crio api to reflect image store cri-o/cri-o#7401
    • CRIO changes to support split filesystem  cri-o/cri-o#7269

  • CAdvisor (google/cadvisor):

    • allow for cadvisor to detect disk stats when the read-only and writeable layers are on separate disks. google/cadvisor#3395

  • CRITools (kubernetes-sigs/critools):

    • adding imagefsinfo endpoint for both container and image filesystems kubernetes-sigs/cri-tools#1295

  • Kubernetes (kubernetes/kubernetes):

    • [KEP - 4191]: Use Cadvisor labels rather than hard coding them into kubelet kubernetes#122438

  • Testing

    • Split disk crio setup test-infra#31502
    • KEP-4191: Split Image Filesystem add end-to-end tests kubernetes#125417

  • Docs (k/website) update PR(s):

    • KEP-4191: Split Image Filesystem add documentation website#46951
    • Add blog post for Separate Image Filesystem for Kubelet website#43971
    • Blog post about Split Image Filesystem

  • Feedback

    • [KEP-4191] Support case when writeable layer and readable layers are on same mount but in different locations kubernetes#126559

• Stable

  • KEP (k/enhancements) update PR(s):
  • Code (k/k) update PR(s):
  • Docs (k/website) update(s):
    -->

Nice to haves:

• Separate SeparateDiskTests from eviction kubernetes#123346

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

[kannon92]

/sig node

[SergeyKanzhelev]

/stage alpha
/milestone v1.29
/label lead-opted-in

[kannon92]

/assign