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The kubelet has no main loop, so start with the list of things it is instead

Artifact — a one-page inventory of the kubelet's sub-managers: for each one, the package that owns it, the one sentence of what it is responsible for, and whether this phase reads it, watches it, or never touches it. Written before any pkg/kubelet/ file is opened.

Rests on — nothing in this phase. It rests on Area 7's rule, which is the strongest in the corpus and is the reason this exercise exists at all: there is no file to enter through, so the map comes from the SIG's prose first.

Topology — none. Two clones and a text editor. Do this on forge beside the ~/src/kubernetes clone P5 made, or on the Mac; nothing here needs a cluster and the next exercise is expensive enough to want the ceiling free.

Setup — the two narrative sources for this phase live in two repositories that are not kubernetes/kubernetes, and both are needed for the whole phase:

ls ~/src/community || git clone --filter=blob:none https://github.com/kubernetes/community ~/src/community
ls ~/src/design-proposals-archive || git clone --filter=blob:none https://github.com/kubernetes/design-proposals-archive ~/src/design-proposals-archive

The archive is not maintained and that is the point: for PLEG, eviction and the cgroup hierarchy it holds the only narrative descriptions that exist, which is why Area 7 leads with it rather than with code.

Do

  1. Read ~/src/community/contributors/devel/sig-node/kubelet.md (item 1) end to end. It is 9.6 KB and it is the map.

  2. Build the inventory as a table. One row per manager the doc names — pod workers, PLEG, the status manager, the probe manager, the volume manager, the container manager (cgroups), the eviction manager, the image manager, the pod-source config layer. For each, fill three columns: package, one sentence, and this phase.

  3. Fill the third column from the phase's module list, not from a guess. Exactly one function is assigned from kubelet.go in this whole phase; find which one and mark every other row of that file's contents as out of scope. Two managers on your list are read in P8 instead — mark them as owed rather than as gaps.

  4. Read ~/src/community/contributors/devel/sig-node/container-runtime-interface.md (item 2) and add a second small table: RuntimeService versus ImageService, and which of your managers talks to which.

  5. Answer module 6.1's first reading question — what the sandbox (pause) container is for — in one line, in your own words, from the doc. You will check that line against a running node in the next exercise.

Expect — a map with roughly nine rows in which most rows are marked not read this phase. That proportion is the finding, not a disappointment: the kubelet is a supervisor tree, this phase reads five of its branches, and the reason kubelet.go is 156 KB is that it wires all of them together. A reader who starts at line 1 of that file is reading the wiring, which explains nothing about any branch.

Write down — the inventory, and the sandbox answer as a single sentence you are willing to be wrong about in public. Keep it; exercise 2 either confirms it or gives you a better one.

Teardown — nothing to delete. Keep both clones for the whole phase; the design-proposals archive is cited by four of the six modules. No topology to release — none was taken.