fix(operator): persist corrected batch checkpoints

[sylvesterkaczmarek]

Description

Closes #588.

EvaluateCurrentBatch can correct stale checkpoint counts or initialize the first batch while returning false. Persist those changes independently of batch completion, so the next reconcile does not reload the obsolete counts. Strategy evaluation remains limited to completed batches, and unchanged state does not trigger a status write.

Regression tests rebuild the rollout from the saved status and verify subsequent failure handling, preservation of stopped compartments, initialization, and unchanged/in-progress/blocked/completed cases. The deployment-policy documentation explains checkpoint corrections. CLI changes are unnecessary because the status fields and reset commands are unchanged.

Validation

• Six regression cases failed on the original code; all ten focused cases pass with the fix.
• make -C operator -o kill unit-tests: all 1,194 specs passed across 15 suites. Only the unrelated process-killing prerequisite was omitted; no tests were skipped.
• make -C operator fmt vet lint: passed, zero lint issues.
• make -C operator build: operator and CLI builds passed.
• git diff --check: passed. Live-cluster end-to-end tests were not run locally.

Checklist

• I am familiar with the Contributing Guidelines.
• My commits are signed off per the DCO and cryptographically signed.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

[github-actions]

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📝 Walkthrough

Walkthrough

The operator rebaselines completed and failed checkpoint counts when compartment membership or outcome counts decrease. It persists corrected status even when no batch advances. It preserves independent counter progress, blocked-only batch state, stop decisions, and completed-rollout state. Reconciliation reports status-only changes, including for strategy-less compartments. Tests and documentation cover correction, persistence, reload, initialization, and non-progress cases.

Priority: ➖ Normal

Estimated code review effort: 4 (Complex) | ~45 minutes

Change: Bug fix · Severity of issue fixed: Medium

Merge Risk: ⚪ Minimal · up to ed639

The checkpoint correction and persistence paths have targeted coverage, with no concrete remaining merge-blocking risk identified.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely identifies the main change: persisting corrected batch checkpoints in the operator.
Description check	✅ Passed	The description directly explains checkpoint correction persistence, related behavior, tests, documentation, and validation for the changeset.
Linked Issues check	✅ Passed	Issue #588 requires persistent correction of stale CompletedNodes and FailedNodes after membership changes. The controller now persists changed batch state independently of batch completion, inclu…
Out of Scope Changes check	✅ Passed	The changes stay within Issue #588. Controller flow changes make checkpoint persistence reachable and separate bookkeeping saves from rollout advancement. Wrapper changes implement membership-aware ch…

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[github-actions]

🌿 Preview your docs: https://nvidia-preview-fix-issue-588.docs.buildwithfern.com/nodewright

[ayuskauskas]

Thanks for this — the diagnosis in #588 is correct, and I checked it rather than assuming, because there is a second writer of CompartmentStatuses that could plausibly have covered this already. It does not: r.ReportState → updateCompartmentStatuses runs at skyhook_controller.go:507, before IntrospectSkyhook at line 535 reaches evaluateCompletedBatches. So the only other persister runs before the correction is computed and never observes it, and the next pass rebuilds from the stale status. The bug is real and the approach is sound. BatchProcessingState is all int/bool, so the new == is a genuine value comparison, and round-tripping the tests through BuildState is the right shape for this class of bug.

Three things below are blocking. The first is a hole in the PR's own stated scope.

Blocking

1. The fix does not apply to compartments without a strategy

buildCompartmentStatus gates the BatchState copy on the compartment having a strategy:

var batchStateCopy *v1alpha1.BatchProcessingState
if compartment.Strategy != nil {
    batchStateCopy = &v1alpha1.BatchProcessingState{ ... }
}

Compartment.Strategy is +optional (deployment_policy_types.go:139-140), and initializeCompartmentsFromPolicy wraps each named compartment with NewCompartmentWrapper(&compartment, batchState) as-is (cluster_state_v2.go:186) without falling back to deploymentPolicy.Spec.Default.Strategy. So a policy with a named compartment that omits strategy produces Strategy == nil, and for that compartment the corrected checkpoint is computed and then written into a CompartmentStatus whose BatchState is nil. The correction is discarded exactly as before this PR.

It is worse than a no-op: NewCompartmentWrapper re-hydrates {CurrentBatch: 1, CompletedNodes: 0} on every rebuild, so the compartment re-derives a positive delta from its already-complete nodes, evaluates a batch, discards it, and repeats every reconcile.

The new documentation sentence — "the operator saves corrected checkpoint counts once the compartment has no nodes in progress" — is false for these compartments, and nothing in the new suite covers Strategy == nil.

2. Persisting the wipe creates a phantom batch when nodes return

The negative-delta branch exists for "nodes move between compartments mid-rollout", which is transient by nature — the node set that left can come back. Making the wipe durable changes what happens on the way back.

Exponential strategy, 100-node compartment, LastBatchSize: 8, checkpoint CompletedNodes: 40. A label edit empties the compartment: deltaCompleted = -40, the checkpoint is wiped to 0, and the new block now persists that. The label is restored and the 40 already-Complete nodes rejoin. Next reconcile deltaCompleted = 40 - 0 = 40, so isComplete is true with batchSize = 40, and EvaluateAndUpdateBatchState(40, 40, 0) sets LastBatchSize = 40. ExponentialStrategy.CalculateBatchSize then returns LastBatchSize * GrowthFactor capped at totalNodes (deployment_policy_types.go:438-443) — 80 nodes cordoned and drained at once with a growth factor of 2, against ~16 on the intended ramp.

Before this PR the wipe was in-memory only, the stale checkpoint of 40 survived in status, the delta on rejoin was 0, and no phantom batch was ever evaluated. This is the one place where discarding the correction was accidentally protective.

3. A correction that advances nothing now aborts the whole reconcile

evaluateCompletedBatches sets changed = true for a pure bookkeeping correction. Back in the loop at skyhook_controller.go:535-542 that runs SaveNodesAndSkyhook and then returns ctrl.Result{RequeueAfter: 2s} from the entire Reconcile, so no later NodeWright in clusterState.skyhooks is processed and no package work is scheduled that cycle.

In the ordinary case this converges — the correction is one-shot and the next pass sees delta 0. Under sustained node churn between compartments, which is exactly the condition this PR targets, corrections can fire on most passes and repeatedly cost a full cycle of package scheduling.

Root cause and altitude

4. The negative-delta condition misdiagnoses node recovery

if deltaCompleted < 0 || deltaFailed < 0 {

A node recovering Erroring → Complete drives currentFailed down while currentCompleted goes up. With checkpoint {CompletedNodes: 10, FailedNodes: 2}, one recovery plus one ordinary completion gives currentCompleted: 12, currentFailed: 1 — deltaCompleted is +2 but deltaFailed is -1, so the branch fires, both checkpoints are overwritten and two real completions are thrown away. The strategy never sees the success, ConsecutiveFailures is not cleared, and LastBatchSize stays stale so the next batch is sized from a batch that ended two batches ago.

To be fair to the PR: this is not a regression. Before the change the same misdiagnosis re-fired on every reconcile and froze the compartment permanently, so persisting it is strictly better. But the fix addresses the discard rather than the faulty condition. Clamping only the field whose delta is actually negative, rather than wiping the whole checkpoint, would handle this case and would also defuse (2), since a membership change would no longer zero a checkpoint that is about to be contradicted.

5. The underlying defect is reconcile ordering, not batch state

Because updateCompartmentStatuses runs before IntrospectSkyhook, every field buildCompartmentStatus computes — Matched, Ceiling, InProgress, Completed, ProgressPercent — is published from a pre-Introspect snapshot and lags by one reconcile. BatchState is the symptom that got noticed. After this PR those other fields refresh only as an accidental side effect of BatchState happening to change.

Calling updateCompartmentStatuses at the end of IntrospectSkyhook, or moving evaluateCompletedBatches ahead of ReportState, fixes the reported bug and the staleness together, without a compartment-specific write path inside the batch loop.

Structure

6. The compartmentStatusEqual guard can never fire

BuildState seeds each compartment's BatchState from Status.CompartmentStatuses[name].BatchState (cluster_state_v2.go:112-113 and 178-179), so previousBatchState is the persisted value whenever an entry exists. Reaching the second guard requires GetBatchState() != previousBatchState, i.e. the new state differs from what is persisted — and compartmentStatusEqual compares *a.BatchState == *b.BatchState (line 1407), so it returns false in exactly that case. When no entry exists, exists is false and the guard is skipped outright. The continue is unreachable.

Dropping the GetBatchState() == previousBatchState pre-filter and keeping the equality check as the single condition is both simpler and matches the existing helper.

7. This reimplements updateCompartmentStatuses

updateCompartmentStatuses (cluster_state_v2.go:1697-1712) already does exactly build → compartmentStatusEqual → write → Updated = true, using !ok || !compartmentStatusEqual(...); the new block writes the logically equivalent exists && compartmentStatusEqual(...) { continue }. Two copies of the same persist-if-different rule now live in one file and have to be kept in sync when a field is added to CompartmentStatus or the nil-map handling changes. A shared persistCompartmentStatus(skyhook, compartment) bool called from both sites would remove the duplication — AGENTS.md asks for the nearest existing pattern to be matched.

8. The continue statements silently bypass the new persistence

Both continues inside the isComplete block now jump past the persistence block. I traced this and nothing is lost today: they are reachable only when EvaluateCurrentBatch returned true from its all-blocked branch (wrapper/compartment.go:253), which is guarded on deltaCompleted == 0 && deltaFailed == 0, and since delta is current - checkpoint, that makes the branch's assignments no-ops.

That reasoning is load-bearing and invisible. The moment someone relaxes that guard so the branch advances a checkpoint for real, these two paths reintroduce precisely the #588 discard this PR is fixing, and no test would catch it. Worth reaching the persistence block via a flag rather than letting continue bypass it, or at minimum naming the invariant in a comment.

Tests and docs

• No Strategy == nil case. Every new entry sets Strategy: &DeploymentStrategy{Fixed: ...}. For strategy compartments a changed BatchState always makes compartmentStatusEqual false, so the guard under test is effectively dead in the suite, while the production path that behaves differently — finding (1) — has zero coverage.
• First-batch init now writes status earlier. The CurrentBatch: 0 → 1 branch returns false and is now persisted, so status.compartmentStatuses appears on the CR earlier in a rollout than before. k8s-tests/chainsaw/deployment-policy/ asserts on compartmentStatuses.<name>.batchState.currentBatch across linear-strategy, multi-compartment and batch-state-reset, including a jsonpath gate at linear-strategy/chainsaw-test.yaml:126. The description notes live-cluster e2e was not run locally; the deployment-policy (k8s-1.36.1) job is queued here and worth confirming green rather than assuming.
• record is reassigned mid-spec. record = rollout.GetSkyhook().NodeWright.DeepCopy() at lines 2276 and 2295 mutates the variable rebuild() closes over, so rebuild() means two different things before and after that line. That is the intent, but nothing names it, and an assertion later moved above the reassignment would silently test the wrong generation of the CR. An explicit saved := ... plus a rebuildFrom(saved) helper would make the two snapshots distinguishable.
• Docs placement. "Checkpoint Corrections" is nested inside "## Batch State Reset", between that section's intro ("Batch state reset handles this automatically") and the "### Auto-Reset Triggers" body that delivers the promised explanation. Corrections neither reset nor advance batch state, so they read as an interruption there and will not be found by someone searching under a heading about resets.

Note on #586

That PR changes which nodes are marked Blocked — every ignored node, not only batch members — and this function branches on blockedCount == len(compartment.GetNodes()) and blockedCount == batchSize. The hunks do not overlap textually (~1244-1305 here versus ~1064 and ~1316 there; docs at line 274 versus 188), but whichever merges second should re-run the other's specs.

[sylvesterkaczmarek]

@ayuskauskas Addressed the review in 3a83fa42f896bac5c5c6cf8cb646083d18edaaf5: membership changes now rebaseline without creating a batch, negative deltas correct only the affected checkpoint, strategy-less compartments persist batch state, and status reporting happens after introspection so bookkeeping saves do not abort the rest of the reconcile. Added regressions for membership leave/return and recovery. Full controller suite (392 specs), wrapper tests, and targeted go vet pass.

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Actionable comments posted: 1

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Inline comments:
In `@operator/internal/controller/cluster_state_v2.go`:
- Around line 1273-1286: In EvaluateCurrentBatch, remove the blockedCount- and
LastBatchSize-based batchSize recovery branches in the batchSize == 0 path,
since this no-success/no-failure case always has blocked nodes. Express the
single rule that such a batch does not advance, while preserving normal
batch-size handling for other outcomes.

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[ayuskauskas]

Re-reviewed at 3a83fa42. This addresses every structural point from the last round, and a couple of them in better ways than I suggested. Suites pass locally for me too (internal/controller 47.1s, internal/wrapper 0.6s).

What landed:

• Strategy-nil hole — buildCompartmentStatus no longer gates the BatchState copy on Strategy != nil. That was the blocking one, and always publishing is the right call: batch state is bookkeeping whether or not a strategy consumes it.
• Negative-delta misdiagnosis — clamping only the field that moved backwards, and keeping the positive delta, is exactly right. An Erroring -> Complete recovery now has its completions counted instead of thrown away.
• Reconcile abort — returning batchAdvanced rather than any-change, and splitting if changed || Updated { Save } from if changed { return }, separates "status needs writing" from "rollout state moved". That is the distinction the old code was missing.
• Ordering — ReportState after IntrospectSkyhook, with the early call kept on the paused path. Compartment status now reflects the state that was just evaluated.
• Duplication and the dead guard — persistCompartmentStatus with updateCompartmentStatuses delegating to it removes both at once.
• continue bypass — the shouldAdvance flag means persistence is always reachable, so the invariant I was worried about no longer has to hold.

Also: UpdateCondition(logger) bool already returned a value that was being discarded, so using it is a tidy-up rather than a signature change. Good catch.

One new issue

RebaselineBatchCheckpoints is gated on any change to Matched, and the branch continues, so genuine progress that happens in the same pass as a membership change is absorbed into the baseline and never evaluated.

Repro — identical node outcomes (two nodes reach Erroring), the only difference being that one node joined the compartment since the status was last written:

Matched in sync (3 == 3):   CurrentBatch=5  FailedNodes=2
Matched stale  (3 != 4):    CurrentBatch=4  FailedNodes=2

FailedNodes is absorbed into the checkpoint either way, but in the second case EvaluateAndUpdateBatchState never runs, so CurrentBatch, LastBatchSize, ConsecutiveFailures and ShouldStop all stay where they were. On the next reconcile Matched agrees and the delta is 0, so that batch result is permanently lost.

The consequence I would weight heaviest is not the stalled ramp but the stop decision: ConsecutiveFailures never increments for a swallowed batch, so failureThreshold can fail to trip and a failing rollout keeps going. On a cluster with an autoscaler or rolling node replacement, Matched changes routinely over the life of a long rollout, so this is not a rare path.

To be clear about what the guard is doing right: the same repro shows it is what suppresses the rejoin phantom batch, which is the thing it was added for. The underlying difficulty is that counting alone cannot distinguish "nodes rejoined carrying completions earned in an earlier membership epoch" from "nodes made progress just now" — and the guard currently assumes the former in both cases.

A direction that keeps the phantom fix without the swallow: have the rebaseline absorb at most the membership delta rather than resetting to the absolute current count, and drop the continue so any residual genuine progress is still evaluated in the same pass. If one node joined and two nodes finished, at most one of those completions can be attributable to the new member.

Worth a test for the shape above — a compartment whose Matched changed in the same pass that nodes reached a definitive outcome, asserting the batch still advances.

[sylvesterkaczmarek]

@ayuskauskas Addressed the remaining membership-churn case in 768eee18.

The rebaseline now absorbs only the terminal-count change explainable by the membership delta and then evaluates any residual progress in the same reconcile. I added the exact regression shape from your comment: Matched changes 3→4 while two nodes become Erroring; one outcome can be attributed to the joined member, while the residual failure still advances the batch and trips failureThreshold.

I also removed the unreachable blocked-count/LastBatchSize recovery branches raised by CodeRabbit.

Validation: controller suite 393/393 specs passed with the repo Kubernetes 1.36 envtest assets; wrapper tests passed; targeted go vet and git diff --check passed. The follow-up commit is DCO-signed and GitHub verifies its SSH signature.

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Actionable comments posted: 1

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Inline comments:
In `@operator/internal/wrapper/compartment.go`:
- Around line 251-253: Replace the membershipDelta-only logic in the compartment
batch-state update with identity- and terminal-state-aware tracking of added and
removed members. In the membershipDelta > 0 path around absorb and
BatchState.CompletedNodes/FailedNodes, absorb only terminal changes attributable
to the joining or leaving members, so unrelated existing-node failures are
preserved. Update the regression in the cluster-state controller test to expect
both existing-node failures.

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[sylvesterkaczmarek]

@ayuskauskas Final follow-up: signed commit 978e7e2 addresses the last CodeRabbit correctness finding by preserving existing-node failures during membership churn; that review thread is now resolved. Could you re-review the current head when convenient?

[lockwobr]

@sylvesterkaczmarek ci is failing because of linting issues. Please address went you have a chance. Thanks for contributing.

[sylvesterkaczmarek]

Thanks for the heads-up. Addressed the two lint failures in signed commit ed639a36: the post-introspection save/requeue logic is extracted so Reconcile is back under the cyclomatic-complexity limit, and persistCompartmentStatus no longer returns an unused boolean. make lint now passes with 0 issues; the wrapper tests pass and the controller package compiles. The full controller suite could not start locally because the envtest etcd binary is not installed, so I am leaving that to CI rather than claiming it passed.

[ayuskauskas]

Re-reviewed at 978e7e2f. The direction is right, previousNodeStatus was the correct answer to the question I left open in round 2, and the remaining defect is in its input rather than its logic. Two blocking items, both small.

A correction I owe you first

My round 2 review told you to "have the rebaseline absorb at most the membership delta rather than resetting to the absolute current count, and drop the continue." That is what 768eee18 does, faithfully. In the same review I also wrote that "counting alone cannot distinguish 'nodes rejoined carrying completions earned in an earlier membership epoch' from 'nodes made progress just now'" — and then prescribed a counting-based fix anyway without resolving that contradiction. 978e7e2f is you answering a question I should have answered myself.

I had also drafted a round 4 asking you to change the bound at compartment.go:265 to currentCompleted - previouslyCompleted. That was wrong, and I'm glad I traced it first: it fails your own test at cluster_state_v2_test.go:2330 — in phase 2 the checkpoint is 0 and currentCompleted == previouslyCompleted == 4, so the limit computes to 0, absorb() returns on its limit == 0 guard, and evaluateCompletedBatches returns true where line 2375 expects false. max(0, previouslyCompleted - c.BatchState.CompletedNodes) is the right bound. Keep it.

(For the record, so it doesn't get proposed later: attributing by identity via Status.NodePriority doesn't work either. pruneCompletedNodePriorities deletes a node's entry the moment its status becomes Complete, and it runs immediately before evaluateCompletedBatches in IntrospectSkyhook — any such test would attribute zero successes to every batch.)

Blocking 1 — previousNodeStatus is lossy in the cases the bound depends on

The logic is right, but Status.NodeStatus isn't a dependable record of prior terminal state. Two paths destroy it:

• Departure prunes it. CleanupRemovedNodes runs cleanupNodeMap(status.NodeStatus, ...) against skyhook.GetNodes(). A node that leaves the skyhook's node set — selector edit, node delete/recreate — loses its entry while away. Returning still Complete, it has no entry, so completedLimit is 0, absorption is skipped, and it lands as a phantom successful batch. (Compartment-to-compartment moves are fine — those nodes stay in GetNodes() and keep their entry.)
• Pause and disable overwrite it. UpdateSkyhookPauseStatus sets every node to StatusPaused, and IntrospectNode does the same for disabled. After a pause/resume cycle the persisted status is paused for all nodes, so previouslyCompleted and previouslyFailed are both 0 and nothing is absorbed. If membership also changed during the pause — an autoscaler, which I flagged in round 2 as routine on long rollouts — every rejoining complete node phantoms.

Suggested fix: treat "no trustworthy observation of this node's prior state" as "assume already terminal," since a node that is Complete now with no observed prior status did not earn that completion under this reconcile's observation.

wasTerminal := func(name string, want v1alpha1.Status) bool {
	prev, ok := previousNodeStatus[name]
	// Missing or operator-imposed placeholder means we never observed this node's
	// real prior state: CleanupRemovedNodes prunes departed nodes, and pause/disable
	// overwrite every entry. Treat it as already-terminal so a rejoining complete
	// node is absorbed as churn rather than counted as batch progress.
	if !ok || prev == v1alpha1.StatusPaused || prev == v1alpha1.StatusDisabled {
		return true
	}
	return prev == want
}

Two test entries under the existing Describe would cover it: a rejoining Complete node absent from previousNodeStatus, and one whose entry is StatusPaused — both asserting evaluateCompletedBatches returns false and CurrentBatch is unchanged.

Related, while you're in there: the fixture at cluster_state_v2_test.go:2367-2368 hand-supplies previousNodeStatus[node-0..3] = StatusComplete for a scenario ("all members leave, then return") where production would have pruned exactly those entries. The test passes on a map production can't produce for that case.

Blocking 2 — docs/user-guide/deployment-policy.md is stale

The "Checkpoint Corrections" section (line 271) was written for 3a83fa42 and hasn't moved, but 768eee18 changed the algorithm under it. Two sentences are now false:

• "rebaselines completed and failed checkpoint counts to the current members" — that's the reset-to-absolute behaviour 768eee18 replaced with bounded absorption.
• "Membership changes are bookkeeping, not completed batches: they do not advance the batch" — contradicted by your test at cluster_state_v2_test.go:2383-2426, which asserts CurrentBatch 4→5 and ShouldStop=true on a reconcile where Matched goes 3→4.

Please rewrite both to say churn is absorbed only up to what the churn can explain, and residual genuine progress is still evaluated in the same pass — so one reconcile can both rebaseline and advance. This needs to land in the same PR per CONTRIBUTING.

Deferred to #626 — your call whether to fold any of it in

I've opened #626 for three gaps that are real but out of scope here: net-zero identity churn bypassing the gate, gross-vs-net churn budgeting, and the membershipDelta < 0 branch not consulting previousNodeStatus (which can lose a failure and keep failureThreshold from tripping).

None of these is a regression — before this PR there was no rebaseline at all and every arrival of a complete node phantomed, so you're strictly improving all three. They're limits of a design I asked you for, and I don't want to pile them onto a fourth round. Fold any of them in if you'd like, or leave them and we'll pick them up separately — either is fine by me.

One question

768eee18 also removed the blocked-node handling from evaluateCompletedBatches — the blockedCount computation and the batchSize / LastBatchSize fallbacks — replacing them with a bare if batchSize > 0. I think it converges, since non-blocked members usually give batchSize > 0 and EvaluateCurrentBatch's all-blocked branch still updates checkpoints. But it's a semantic change unrelated to the commit's stated purpose, nothing in the suite pins it, and it touches a path #586 also modifies. Was that intentional?

---

Thanks for sticking with this through three rounds — the previousNodeStatus idea is the right one, and it came from you rather than from me.

[github-actions]

✅ Every non-bot commit on this pull request is now signed off and signed. Thanks!

[sylvesterkaczmarek]

@ayuskauskas Thanks for the careful re-review, especially for tracing the bound before proposing another change. Addressed both blockers in 66bfc662:

• RebaselineBatchCheckpoints now treats a missing, paused, or disabled prior node status as an untrusted observation and therefore already-terminal for churn attribution. I also corrected the all-members-leave/return fixture so departed completed nodes are absent from previousNodeStatus, and added explicit missing/paused regression cases.
• Updated the Checkpoint Corrections docs to describe bounded churn absorption plus residual progress evaluation in the same reconcile.

On the blocked-node question: the removal in 768eee18 was incidental, not intentional. I restored the prior blockedCount/batch-size handling so this PR does not change that behavior while fixing membership churn.

Validation: wrapper tests pass; the controller package compiles with go test ./internal/controller -run "^$"; make -C operator lint reports 0 issues. The full controller suite still cannot start locally because /usr/local/kubebuilder/bin/etcd is absent, so CI will cover those envtest-backed specs.

Please re-review the current head when convenient.

[ayuskauskas]

Re-reviewed at 66bfc662. Both round 4 blockers are addressed and I have no further structural concerns. Approving.

Blocking 1 — previousNodeStatus lossiness. wasTerminal now treats a missing entry, StatusPaused, or StatusDisabled as "no trustworthy prior observation → already terminal". That's the right call, and the comment states the constraint rather than the mechanics. The fixture correction at the all-members-leave/return case matters as much as the code change — the old test asserted against a previousNodeStatus map production can't actually produce for that scenario, so it was pinning the wrong thing.

Blocking 2 — docs. The Checkpoint Corrections rewrite now says churn is absorbed only up to what it can explain and residual progress is evaluated in the same pass, which matches 768eee18's algorithm. Both of the sentences I flagged as false are gone.

On the blocked-node question: thanks for restoring it. I traced the restore — the advance decision is equivalent to the pre-PR logic, with continue rewritten as shouldAdvance = false. The one difference is that an all-blocked compartment now falls through to persistCompartmentStatus instead of skipping persistence entirely, which is the always-persist design from round 2 rather than a behavior change, so that's correct as written.

I also traced one thing that turned out to be a non-issue, recording it so it doesn't get re-raised: this PR changes IntrospectSkyhook's return from "did anything set Updated" to a delta of five specific signals, and there's a second caller at skyhook_controller.go:1321 gating if !changed && skyhook.IsComplete() that nobody updated. It's fine — the paths that leave uninstall work outstanding also flip a node status, so IntrospectNode returns true and the guard is bypassed. Worth knowing the contract narrowed if that guard is ever touched.

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Two non-blocking nits, fold in only if you're pushing anyway for the signature fix below:

• RebaselineBatchCheckpoints still returns a bool that's discarded at its only call site (cluster_state_v2.go:1261). ed639a36 removed exactly this pattern from persistCompartmentStatus for lint and missed the neighbour.
• docs/observability/metrics.md:93 still describes nodewright_rollout_current_batch as "0 if no batch processing". That stopped being true when buildCompartmentStatus began publishing batchState unconditionally in 3a83fa42. This PR updated nine doc pages but not that one.

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Two gates before this can merge, both outside the code:

1. 66bfc662 is unsigned — GitHub reports verified: false, reason: unsigned, and the Commit Requirements check is red. git commit --amend -s -S --no-edit then git pushf. Note the sign-off is present; it's only the -S signature missing.
2. Operator CI is still queued on this head, so the envtest-backed controller specs you couldn't run locally haven't run anywhere yet. I'd like to see that green before merge given how much of this change is covered by exactly those specs.

My approval stands for the code as-is; if CI turns up a failure in the new specs, ping me rather than assuming this approval covers the fix.

[ayuskauskas]

@sylvesterkaczmarek One thing left before this can merge, and it's mechanical rather than a code change.

66bfc662 is not cryptographically signed. GitHub reports verified: false, reason: unsigned, and the Commit Requirements check is red because of it. main has a required_signatures ruleset, so the merge will be refused regardless of approvals until this is fixed.

To be precise about scope, since it would be easy to over-correct here: 66bfc662 is the only affected commit. I checked all seven on the branch:

Commit	Signature	Sign-off
df74ad8a	✅ valid	✅
3a83fa42	✅ valid	✅
768eee18	✅ valid	✅
978e7e2f	✅ valid	✅
6448ba85 (merge from main)	✅ valid	n/a
ed639a36	✅ valid	✅
66bfc662	❌ unsigned	✅

Note the DCO Signed-off-by trailer is already present on 66bfc662 — it's only the -S signature that's missing. The two flags are independent, which is exactly the case that's easy to trip on when amending.

Because it's the tip commit, this is a one-liner. Please don't rebase the whole branch — the other six are fine and a full rewrite would drop the main merge:

git commit --amend -s -S --no-edit
git pushf   # repo alias for: git push --force-with-lease --force-if-includes

If signing isn't configured on this machine yet, one-time setup so you only ever need -s from here on:

git config gpg.format ssh
git config user.signingkey ~/.ssh/id_ed25519.pub
git config commit.gpgsign true

The key also has to be registered on your GitHub account as a signing key (a key added only as an auth key won't verify): https://github.com/settings/keys

Two notes on what happens after:

• The amend produces a new SHA, which may dismiss my approval depending on branch protection. If it does, ping me and I'll re-approve — the code review is done, nothing about the amend changes my assessment.
• Operator CI is still queued on the current head, so the envtest-backed controller specs you couldn't run locally haven't reported yet. The force-push will re-trigger them. I'd like to see that green before merge given how much of this change lives in exactly those specs.

[sylvesterkaczmarek]

Fixed the mechanical signature issue only. I amended the tip commit with the registered SSH signing key and force-pushed with lease; the new tip is 1bbcbb8f2dce6d932e1f46c4c66e14da81a86cce, and GitHub reports the commit signature as verified. No code or message changes.

[ayuskauskas]

Confirming on the re-signed head 1bbcbb8f.

Signing is resolved — all seven commits now verify, and Sign-off and signature is green. I diffed 66bfc662 against 1bbcbb8f and the tree is byte-identical, so this was a pure re-sign with no content change from what I reviewed.

CI is fully green, which closes the one open item from my previous approval. The envtest-backed controller specs you couldn't run locally have now run: Operator CI passed, along with the full e2e matrix — e2e/core, e2e/interrupt, e2e/lifecycle, e2e/uninstall across k8s 1.34.11 / 1.35.8 / 1.36.4 / 1.37.0, plus deployment-policy (12m48s) and cli-e2e. The deployment-policy suite is the one I most wanted to see, since that's where this change lives.

Approving. Ready to merge from my side.

The two nits from my last review (RebaselineBatchCheckpoints returning a discarded bool at cluster_state_v2.go:1261, and the stale nodewright_rollout_current_batch description at docs/observability/metrics.md:93) are unaddressed, which is fine — they were explicitly non-blocking and I'd rather not churn a green, signed head for them. I'll pick them up separately unless you'd prefer to fold them in.

Thanks for the patience across five rounds — the previousNodeStatus approach was yours, and it's the part of this that I think will hold up.

[sylvesterkaczmarek]

Thanks for the careful review rounds and for merging this. The full deployment-policy/e2e matrix going green on the re-signed head was a useful final check.