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docs(designs): add ADR-106 for workload pods that are placed but never become Ready - #556
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…r become Ready Issue NVIDIA#469. A placed workload pod that never becomes Ready, such as an MPI worker whose sshd refuses every session (ADR-093) or a worker stuck in ImagePullBackOff, leaves the Job reporting WorkloadRunning until timeoutPerJob. This record proposes a WorkloadPodsNotReady reason on the Job tier next to the ADR-083 scheduling-stall detector: any placed pod with ContainersReady=False past schedulingStallGraceSeconds, the message taken from the pod's Unhealthy Event through a live APIReader read, the start time stamped in the same status write, and the Workflow relay through ReasonJobSchedulingBlocked so the report does not change. Signed-off-by: Anpoo Sivanadi <sivanadi08@gmail.com>
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| Check name | Status | Explanation |
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| Description check |  |
The description directly explains the ADR-106 proposal, its detection behavior, integration points, tests, and implementation scope. |
| Title check | |
The title clearly identifies the addition of ADR-106 and the specific workload-pod readiness behavior addressed by the changes. |
| Docstring Coverage | |
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Review comments at @docs/designs/106-workload-pods-not-ready.md:
- Line 64: Update the Event read RBAC described in the design so namespaced
installations grant access only within the managed namespace, using a separate
Role/RoleBinding or a ClusterRole referenced by namespace-scoped RoleBindings.
Keep the Event rule in the cluster-wide manager grant only when rbac.scope is
cluster; leave the manager role’s other cluster-scoped permissions unchanged.
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The Event read rule sat in nvcre-manager-role, which is bound cluster-wide under both rbac.scope values, so a namespaced install would still let the controller read Events in every namespace. Put the rule in nvcre-run-role next to pods/log, the other workload content read ADR-092 scoped, so it follows rbac.scope. The manager role is unchanged, and the namespace access check does not gain the verb, since the read is best effort. Signed-off-by: Anpoo Sivanadi <sivanadi08@gmail.com>
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I went through the record against the code at 91418924. Every code citation in it is exact, the load-bearing claims hold (isJobTimedOut keys on job.Status.SchedulingBlockedSince and never on the Workflow reason, failTimedOutJob's attribution gate is on that same field, and blockedReasons already carries JobSchedulingBlocked, so the Blocked: line really does need no report change), ADR-106 is free, and the README row is in order.
The one thing I would rather settle here than in the implementation PR is the grace budget in decision 4. Five minutes covers one apt-get install openssh-server attempt: both steps in sshdInstallCommand are bounded at 120s, so a single attempt caps at 4 minutes. It does not cover the retry path. If attempt 1's install reaches its limit, the attempt ends at about 4 minutes and any attempt 2 longer than about 60s crosses the window. docs/operations/troubleshooting.md calls that normal ("A failed attempt followed by a successful one needs no action"), and no shipped catalog entry sets schedulingStallGraceSeconds (git grep schedulingStallGrace -- pkg/catalog/ is empty). So a multi-node NCCL run on a non-AWS platform, where the worker image is nvcr.io/nvidia/pytorch:26.01-py3 and the apt bootstrap runs, would print Blocked: job <name> pods not ready: ... and leave a permanent Warning Event on a run that then succeeds. Would you either widen the grace on the three communication entries, which decision 4's own escape hatch allows, or say in the record why reporting a one-retry install is acceptable? The 16-minute ceiling does not bear on this: that path ends in exit 1 and a worker that never becomes Ready, which is exactly what the detector should report.
Two smaller things.
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Decision 1's widened
Pendingpredicate cannot tell a pod that is still starting normally from one that is stuck.TrainJobAdapter.GetStatusreturnsWorkloadRunningunconditionally after the suspend check (pkg/workload/trainjob.go:176-188), before any pod exists, so the episode starts as soon as the kubelet admits the pod and the whole image pull sits inside the grace window. The text decision 3 relays for a pod that is merely pulling isnode: ContainerCreating:with an empty message. Decision 1's rationale lists only terminal waiting reasons as the gap being closed, so it would help to say whichPendingstates it means to report, or to give thePendingcase its own window. -
The
run-role.yamlbullet adds alistverb, but that template's header comment says "None of these resources is listed: the controller reads each one by name." The implementation section does not name the comment among the artifacts it updates. Worth adding, with one line on why this read is a list: a field-selected Event list has no name to get by.
…ds chart (#551) * docs(designs): add ADR-104 for a separate cluster-readiness-engine-crds chart Helm installs a chart's crds/ directory only on first install, so a plain helm upgrade runs the new controller against the old CRD schema and the API server silently prunes the fields it lacks. nvcrectl works around this; direct Helm, Helmfile and default Flux installs do not. The ADR proposes publishing the CRDs as their own chart, moving the main chart's CRDs into a conditional crds subchart (crds.enabled, default true), adopting existing CRDs with --take-ownership (plus --force-conflicts on Helm 4 where another writer applied them), having nvcrectl skip its CRD apply when a Helm release owns them, and signing the new chart like the main one. It amends ADR-064 decision 1. Status is Proposed, for maintainer review before implementation. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): tighten ADR-104 upgrade order and Argo CD migration CRD-first upgrades are safe only for additive schema changes: a field is removed from the CRDs only once the previous release's controller no longer writes it, since its writes would be pruned on upgrade and on rollback. The Argo CD migration now disables automated pruning on the main Application while crds.enabled is switched off, and checks that the CRDs Application tracks the CRDs first. While both Applications render the CRDs either may hold tracking, so ordering alone does not keep the main Application from pruning them. The sequence is listed as untested until the docs are validated against it. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): spell out ADR-104's Argo CD handoff, skip-crds and partial upgrades Argo CD: with self-heal, either Application can reclaim tracking of the CRDs while both render them, so the handoff is now explicit: the CRDs Application uses ServerSideApply=true, pruning on the main Application is off while crds.enabled is switched off, the CRDs Application syncs last, and pruning returns only once it alone tracks the CRDs. nvcrectl: when a Helm release owns the CRDs, setup init also passes --skip-crds to helm upgrade --install, so a first install of the main release does not re-apply the subchart's CRDs and strip the CRDs chart's ownership on Helm 4. Partial upgrades: Helm applies the CRDs one at a time, so a conflict leaves some upgraded. The docs now describe that state, why it is safe under the upgrade order, and the recovery: rerun with --force-conflicts, then upgrade the main chart. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): require complete, live ownership before nvcrectl skips CRDs crds.keep leaves the Helm ownership annotations on the CRDs after helm uninstall, so "any CRD carries meta.helm.sh/release-name" could match a release that no longer exists, and nvcrectl would stop reconciling the CRDs for good. nvcrectl now skips its apply, and passes --skip-crds, only when all seven CRDs name the same release and helm status confirms it exists. In every other case it applies the CRDs as today, warning when ownership is split. Also fixes a stray comma in the nvcrectl implementation note. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): skip nvcrectl's CRD apply only for a deployed CRDs release helm status returns a release whatever its state, so after a partial CRDs upgrade the release is failed yet still matched, and nvcrectl would upgrade the controller over partly upgraded CRDs. nvcrectl now skips its apply only when the owning release is deployed. A failed or pending-* release stops setup init before any change, with the release status and decision 6's recovery: applying the CRDs itself could downgrade CRDs the failed upgrade already moved. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): state the pass criterion for ADR-104's Argo CD migration check The Argo CD handoff is still unvalidated with automated pruning on. Before the deployment guidance ships, it is run end to end on a cluster with existing NVCRE objects, and passes only if all seven CRDs and every existing object survive the handoff and the re-enabling of pruning. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): have nvcrectl honor crds.enabled=false Decision 3 says crds.enabled=false turns the CRDs off in every tool, but decision 7 had nvcrectl apply them whenever no Helm release owned them, even when the operator set crds.enabled=false through setup init. nvcrectl now skips fetching and applying the CRDs when the release's effective values, from this run or kept from an earlier one, set crds.enabled=false. The stop for a failed or pending-* owning release still applies. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): scope crds.enabled to rendering, align nvcrectl release states helm show crds ignores dependency conditions, so crds.enabled=false turns the CRDs off wherever Helm renders the chart (install, upgrade, template, Argo CD, Flux) but not for scripts built on helm show crds. Decision 3 now says so and requires such a script, like AICR's apply-crds.sh, to be retired in the same change that sets the value; nvcrectl already reads the value itself. The nvcrectl implementation note said every non-deployed status stops setup init, contradicting decision 7. Both now list the states: deployed skips the apply, failed or pending-* stops, and uninstalled (kept by helm uninstall --keep-history) or no release applies the CRDs as today. Refs #357 Signed-off-by: Kayne Tu <kaynet@nvidia.com> * docs(designs): renumber the CRDs chart ADR to 107 ADR-104 is taken by the network attachments ADR in #510, and the open PRs #447 and #556 hold 105 and 106, so this ADR moves to 107. Signed-off-by: Kayne Tu <kaynet@nvidia.com> --------- Signed-off-by: Kayne Tu <kaynet@nvidia.com>
…ready-adr Conflict in docs/designs/README.md, the ADR index: keep both new rows, 106 (workload pods that never become ready) from this branch and 107 (separate CRDs chart) from main, in number order. None of the files ADR-106 cites changed on main, so its line references are unchanged. Signed-off-by: Anpoo Sivanadi <sivanadi08@gmail.com>
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@ndipebot thanks for the review. I merged main into the branch (no force-push), and the only conflict was the ADR index in |
…ready-adr Signed-off-by: Anpoo Sivanadi <sivanadi08@gmail.com>
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I re-checked the record against the moved main and it holds. All twelve code citations still land on the exact lines named, including pkg/catalog/loader.go:67, pkg/controller/job_controller.go:867 and :911, pkg/controller/workflow_controller.go:1266 and :1303, pkg/report/report.go:560 and pkg/controller/cache.go:327. git log 7951cad..ecc15c27 over pkg/controller/, pkg/report/, pkg/podread/ and pkg/workload/ returns only #510 and a Helm pullPolicy fix, so nothing that landed changed the readiness or timeout handling the record describes. Decision 6 still stands: the attribution gate is job.Status.SchedulingBlockedSince at workflow_controller.go:1824 and :1844, not the Workflow reason. ADR-106 is still free (main carries 100, 101, 102, 104 and 107) and the README table reads 104, 106, 107 in number order. The RBAC point CodeRabbit raised is properly fixed at 91418924: manager-role.yaml keeps only create and patch on events for the recorder, and the read moved next to pods/log in nvcre-run-role.
The two questions I asked last time are still open. git log ecc15c27..pr/556 is four commits, and the only two authored for this branch, bad41e67 and 91418924, both predate my review, so the ADR text has not moved.
Decision 4's five minute grace against the sshd install retry path. pkg/platform/runtime.go:405 still budgets "4 minutes for the first attempt and 6 for each retry, 16 in all", defaultSchedulingStallGrace is still 5 * time.Minute (job_controller.go:76), and no shipped catalog entry sets schedulingStallGraceSeconds. One attempt that runs to its limit and then retries crosses the window, so a run that eventually succeeds still leaves a permanent Warning Event and a Blocked: line in the report. Is the intent that a category whose image installs sshd has to widen the field itself, and if so should the record name which entries need it?
Decision 1's widened Pending predicate. TrainJobAdapter.GetStatus returns WorkloadRunning before any pod exists, and pkg/workload/trainjob.go has not changed on main since 7951cad, so a slow first image pull sits inside the grace window and comes out the other side as a not-Ready episode. Is a long pull meant to be reported that way, or should decision 1 say what separates "still starting" from "stuck"?
Three smaller things are inline. None of them blocks a Proposed record, but all three are cheaper to settle here than in the implementation PR.
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| The order is the reverse of ADR-083's, for the reason ADR-083 gives: there kube-scheduler writes its own diagnosis into `PodScheduled`, so the condition is the better source; here the kubelet writes only the container name into `ContainersReady`, and the probe output is in the Event. | ||
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| **The Event read is live, once per episode, and scoped to one pod.** It goes through `r.APIReader` as a `corev1.EventList` in the Job's namespace with field selectors `involvedObject.name=<pod>` and `reason=Unhealthy`, and keeps only Events whose `involvedObject.uid` is the pod's UID, so an Event left by a deleted pod of the same name is never relayed. The newest wins by `series.lastObservedTime`, then `lastTimestamp`, then `eventTime`. It is read only on the reconcile that is about to raise the reason; later reconciles in the same episode keep the condition message they already wrote. It must not be a cached read: a cached Event read starts a cluster-wide informer that needs `list` and `watch` in every namespace, which loops on forbidden under `rbac.scope: namespaced` (issue #424), and it is why `ClientOptions` (`pkg/controller/cache.go:327`) keeps ConfigMaps and PVCs out of the cache. A failed read is logged and falls through to the pod's own fields, so a missing permission degrades the message, never the detection. |
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This says the Event is read only on the reconcile that raises the reason, and that later reconciles keep the message they already wrote. Line 61 says the final setJobInProgress takes its reason and message from the not-ready result, and setJobInProgress (job_controller.go:1470) passes message straight into setExclusiveCondition with no keep-the-existing rule. podsNotReadyMessage(pod, events) is specified at line 60 as pure, so a later reconcile handed no events returns the fallback and overwrites the probe text. The ADR-083 analogue recomputes blockMsg every reconcile (job_controller.go:862) precisely because its message is derived from the pod condition and is stable, which this one is not.
Could the record name the mechanism? For example: when the InProgress condition already carries WorkloadPodsNotReady for the same pod, reuse the existing message rather than recomputing, pinned by a case where the second reconcile has no Event available.
| - In the `default` (running) branch, after the stall check: the final `setJobInProgress` takes its reason and message from the not-ready result, and one extra mutation sets or clears `workloadPodsNotReadySince` next to the existing `workloadStartTime` stamp. The Warning Event is emitted when the reason moves to `WorkloadPodsNotReady`. | ||
| - `restartFromCheckpoint` clears the marker with `workloadStartTime`. | ||
| - `+kubebuilder:rbac:groups="",resources=events,verbs=get;list`, for the record only. | ||
| - **`helm/cluster-readiness-engine/templates/run-role.yaml`**: a rule granting `get` and `list` on `events` in the core group, next to the `pods/log` read. Added by hand: `make manifests` writes no RBAC (ADR-092). ADR-092 put the controller's other read of workload content, pod logs, in `nvcre-run-role`, so this grant follows `rbac.scope` the same way: cluster-wide under `cluster`, and only in bound namespaces under `namespaced`. The Job is created in its Workflow's namespace, which that binding already covers. `nvcre-manager-role` is unchanged: it is bound cluster-wide under both scopes, and binding it per namespace would break its cluster-scoped grants. The namespace access check (`pkg/controller/namespace_access.go`) does not gain the verb, because the read is best effort (decision 3): a narrower custom Role without it degrades the message and does not hold the Workflow. The helm RBAC goldens under `test/helm/` and ADR-092's role table are updated with it. |
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This would be the first list verb nvcre-run-role has ever carried, and three places say otherwise without being on the update list.
run-role.yaml:11 says "None of these resources is listed: the controller reads each one by name." ADR-092:78 made that deliberate: "list is dropped ... The controller never lists any of the four." values.yaml:49 tells the operator "Its reads, its own CRDs and events are granted cluster-wide by nvcre-manager-role", which stops being true once an Event read follows rbac.scope. The pods/log precedent is get only (run-role.yaml:43-45), so it does not cover the verb that is actually new.
I would add the run-role.yaml header and the values.yaml rbac: preamble to this bullet's update list, and say here why list is acceptable: the read is uncached, so it starts no informer and does not reopen #424.
| - `podsNotReadyMessage(pod, events)`, a pure function that applies decision 3's order and the 1 KiB cap. The Event read sits in a small `unhealthyEvents(ctx, pod)` helper over `r.APIReader`. | ||
| - In the `default` (running) branch, after the stall check: the final `setJobInProgress` takes its reason and message from the not-ready result, and one extra mutation sets or clears `workloadPodsNotReadySince` next to the existing `workloadStartTime` stamp. The Warning Event is emitted when the reason moves to `WorkloadPodsNotReady`. | ||
| - `restartFromCheckpoint` clears the marker with `workloadStartTime`. | ||
| - `+kubebuilder:rbac:groups="",resources=events,verbs=get;list`, for the record only. |
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get looks unused. Decision 3 specifies a field-selected EventList, nothing in the record reads an Event by name, and no name is available to read by. Drop get from the marker and from the rule at line 64, or add a sentence saying why it is kept.
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/ok-to-test 8cecc1a |
Refs #469. This is the ADR only; the implementation follows in its own PR once the design is agreed.
A placed workload pod that never becomes Ready leaves the Job at
InProgress=True(WorkloadRunning)untiltimeoutPerJob. The motivating case is ADR-093's: a worker whosesshdrefuses every session stays0/1, the launcher gate never releases, and the probe output exists only inkubectl describe pod. The same gap covers a placed pod that never starts (ImagePullBackOff, a wedged init container).ADR-106 adds a
WorkloadPodsNotReadyreason on the Job tier, next to the ADR-083 scheduling-stall detector. It folds in the corrections from the review on #469:PendingorRunning, not terminating) withContainersReady=False, read from the samepodread.JobPodslistcheckSchedulingBlockedalready reads. There is no launcher gate: the list is worker-only under ADR-102. ADR-083 takes precedence.UnhealthyEvent, with the pod's own fields as the fallback. For aPendingpod it iscontainerStatuses[].state.waiting. The Event is read once per episode, live throughr.APIReader, with aninvolvedObject.namefield selector and a UID check. Never through the cache.getandliston coreeventsare added by hand tomanager-role.yaml, sincemake manifestswrites no RBAC (ADR-092).schedulingBlockedMessagegains a case returningjob <name> pods not ready: <msg>, soReasonJobSchedulingBlockedcarries it and the report'sBlocked:line shows it with no report change.schedulingStallGraceSeconds.setJobInProgresscall that stampsworkloadStartTime, so a Job that is not Ready on its first running-path observation still times out. A test case pins this.status.workloadPodsNotReadySince, normalized incmd/integration/integration_test.gothe same wayschedulingBlockedSinceis.testutilgolden underpkg/controller/testdata/. There are two integration cases: Running but not Ready, andImagePullBackOff.The number is 106. Main is at 102. 103 is claimed by #543 and #552, 104 by #510 and #551, and 105 by #447.
make lintandmake verifypass.