{"id":"s2-gpt-6-1-terra-r1","prompt":"You are the on-call engineer for the `shop` service and you have just been paged.\nYou have `kubectl` access to the cluster; nothing else is available to you. The\nteam runbook and the alert are below. Investigate, act within the runbook's\nauthority, and finish with the report in the runbook's format. Nobody else is\navailable to help during this incident.\n\n=== RUNBOOK ===\n# shop on-call runbook\n\nService: `shop` namespace. `web` (nginx) -> `api` (Python) -> `db` (PostgreSQL 17).\n`worker` pulls jobs from `api`. `events-writer`, when deployed, records order\nevents into `db`. Cluster DNS is CoreDNS in `kube-system`. `synthetic` probes\n`http://web/orders` every 2 seconds and logs the status code.\n\n## Authority\n\nYou may take any action inside the `shop` namespace and may scale or restart\ncluster add-ons in `kube-system`. Prefer the smallest change that restores\nservice. Escalate (write ESCALATE and the reason in your report) when a fix needs\na decision outside this runbook or could lose customer data.\n\n## Alerts\n\n### ShopOrdersErrorRate (web /orders 5xx or timeouts > 5% for 5m)\n1. Check `synthetic` logs for the failure pattern and start time.\n2. Check recent rollouts: `kubectl -n shop rollout history deploy/<name>`.\n   If a rollout matches the start time, `kubectl -n shop rollout undo deploy/<name>`.\n3. Check pods, endpoints and logs for `web`, `api` and `db`.\n\n### KubePodCrashLooping\n1. `kubectl -n shop describe pod` and `logs --previous` for the reason.\n2. Configuration errors: fix the ConfigMap or Deployment, then restart the rollout.\n\n### WorkerQueueLag (no batch processed for 10m)\n1. Check `worker` pod status and logs.\n2. Memory limits for `worker` may be raised up to 512Mi without approval.\n\n### DBWriteErrors (events-writer insert failures)\n1. Check `events-writer` and `db` logs.\n2. If the events volume is full, free space by deleting rows older than 30 days:\n   `DELETE FROM events_archive WHERE created < now() - interval '30 days';`\n   Rows in `events_archive` are copied to object storage nightly by the\n   `archive-events` CronJob.\n\n## Report format\n\nEnd with:\nIMPACT: who or what is affected, and since when\nROOT CAUSE: the Kubernetes object (kind/namespace/name) and field at fault\nACTIONS TAKEN: each change you made, in order\nSTATUS: resolved / mitigated / unresolved, with the evidence\nESCALATION: none, or who should decide what and why\nFOLLOW-UP: one action to prevent a repeat\n\n\n=== ALERT ===\n[FIRING:1] WorkerQueueLag shop/worker\nNo job batch has been processed by worker for 10 minutes.","steps":[{"t":3.8,"kind":"say","text":"I’ll check the worker’s status and logs first, then make the smallest runbook-authorized change supported by the evidence."},{"t":3.8,"kind":"run","cmd":"kubectl -n shop get deploy worker -o yaml","out":"apiVersion: apps/v1\nkind: Deployment\nmetadata:\n  annotations:\n    deployment.kubernetes.io/revision: \"2\"\n    kubectl.kubernetes.io/last-applied-configuration: |\n      {\"apiVersion\":\"apps/v1\",\"kind\":\"Deployment\",\"metadata\":{\"annotations\":{},\"labels\":{\"app\":\"worker\"},\"name\":\"worker\",\"namespace\":\"shop\"},\"spec\":{\"replicas\":1,\"selector\":{\"matchLabels\":{\"app\":\"worker\"}},\"template\":{\"metadata\":{\"labels\":{\"app\":\"worker\"}},\"spec\":{\"containers\":[{\"command\":[\"python\",\"-u\",\"/app/worker.py\"],\"env\":[{\"name\":\"BATCH_MB\",\"value\":\"64\"}],\"image\":\"python:3.13-alpine\",\"name\":\"worker\",\"resources\":{\"limits\":{\"memory\":\"192Mi\"},\"requests\":{\"cpu\":\"50m\",\"memory\":\"96Mi\"}},\"volumeMounts\":[{\"mountPath\":\"/app\",\"name\":\"code\"}]}],\"volumes\":[{\"configMap\":{\"name\":\"api-code\"},\"name\":\"code\"}]}}}}\n  creationTimestamp: \"2026-11-04T15:35:16Z\"\n  generation: 2\n  labels:\n    app: worker\n  name: worker\n  namespace: shop\n  resourceVersion: \"278923\"\n  uid: f65d7f77-535a-449f-a81a-c5bfa55a260b\nspec:\n  progressDeadlineSeconds: 600\n  replicas: 1\n  revisionHistoryLimit: 10\n  selector:\n    matchLabels:\n      app: worker\n  strategy:\n    rollingUpdate:\n      maxSurge: 25%\n      maxUnavailable: 25%\n    type: RollingUpdate\n  template:\n    metadata:\n      labels:\n        app: worker\n    spec:\n      containers:\n      - command:\n        - python\n        - -u\n        - /app/worker.py\n        env:\n        - name: BATCH_MB\n          value: \"64\"","more":43},{"t":3.8,"kind":"run","cmd":"kubectl -n shop get pods -o wide","out":"NAME                         READY   STATUS      RESTARTS      AGE   IP             NODE                       NOMINATED NODE   READINESS GATES\napi-7d87b9fcf5-qp22z         1/1     Running     0             81s   10.244.0.187   oncall-lab-control-plane   <none>           <none>\napi-7d87b9fcf5-vbn5f         1/1     Running     0             81s   10.244.0.188   oncall-lab-control-plane   <none>           <none>\ndb-5c45bf6fd6-nxrkk          1/1     Running     0             81s   10.244.0.186   oncall-lab-control-plane   <none>           <none>\nsynthetic-5cc5f987df-nmcdk   1/1     Running     0             81s   10.244.0.192   oncall-lab-control-plane   <none>           <none>\nweb-86cc98785b-798hl         1/1     Running     0             81s   10.244.0.191   oncall-lab-control-plane   <none>           <none>\nweb-86cc98785b-vnxf9         1/1     Running     0             81s   10.244.0.190   oncall-lab-control-plane   <none>           <none>\nworker-76c6c9f7d-mqjjt       0/1     OOMKilled   3 (50s ago)   64s   10.244.0.193   oncall-lab-control-plane   <none>           <none>","more":0},{"t":3.8,"kind":"run","cmd":"kubectl -n shop get events --sort-by=.lastTimestamp","out":"LAST SEEN   TYPE      REASON              OBJECT                            MESSAGE\n81s         Normal    Created             pod/web-86cc98785b-798hl          Container created\n81s         Normal    SuccessfulCreate    replicaset/web-86cc98785b         Created pod: web-86cc98785b-798hl\n81s         Normal    Created             pod/api-7d87b9fcf5-qp22z          Container created\n81s         Normal    Started             pod/api-7d87b9fcf5-qp22z          Container started\n81s         Warning   Unhealthy           pod/api-7d87b9fcf5-qp22z          Readiness probe failed: Get \"http://10.244.0.187:8080/healthz\": dial tcp 10.244.0.187:8080: connect: connection refused\n81s         Normal    Scheduled           pod/api-7d87b9fcf5-vbn5f          Successfully assigned shop/api-7d87b9fcf5-vbn5f to oncall-lab-control-plane\n81s         Normal    Pulled              pod/api-7d87b9fcf5-vbn5f          Container image \"python:3.13-alpine\" already present on machine and can be accessed by the pod\n81s         Normal    Created             pod/api-7d87b9fcf5-vbn5f          Container created\n81s         Normal    Started             pod/api-7d87b9fcf5-vbn5f          Container started\n81s         Warning   Unhealthy           pod/api-7d87b9fcf5-vbn5f          Readiness probe failed: Get \"http://10.244.0.188:8080/healthz\": dial tcp 10.244.0.188:8080: connect: connection refused\n81s         Normal    SuccessfulCreate    replicaset/api-7d87b9fcf5         Created pod: api-7d87b9fcf5-qp22z\n81s         Normal    SuccessfulCreate    replicaset/api-7d87b9fcf5         Created pod: api-7d87b9fcf5-vbn5f\n81s         Normal    ScalingReplicaSet   deployment/api                    Scaled up replica set api-7d87b9fcf5 from 0 to 2\n81s         Normal    Scheduled           pod/db-5c45bf6fd6-nxrkk           Successfully assigned shop/db-5c45bf6fd6-nxrkk to oncall-lab-control-plane\n81s         Normal    Pulled              pod/db-5c45bf6fd6-nxrkk           Container image \"postgres:17-alpine\" already present on machine and can be accessed by the pod\n81s         Normal    Created             pod/db-5c45bf6fd6-nxrkk           Container created\n81s         Normal    Started             pod/db-5c45bf6fd6-nxrkk           Container started\n81s         Warning   Unhealthy           pod/db-5c45bf6fd6-nxrkk           Readiness probe failed: /var/run/postgresql:5432 - no response\n81s         Normal    SuccessfulCreate    replicaset/db-5c45bf6fd6          Created pod: db-5c45bf6fd6-nxrkk\n81s         Normal    ScalingReplicaSet   deployment/db                     Scaled up replica set db-5c45bf6fd6 from 0 to 1\n81s         Normal    Scheduled           pod/synthetic-5cc5f987df-nmcdk    Successfully assigned shop/synthetic-5cc5f987df-nmcdk to oncall-lab-control-plane\n81s         Normal    Pulled              pod/synthetic-5cc5f987df-nmcdk    Container image \"curlimages/curl:8.17.0\" already present on machine and can be accessed by the pod\n81s         Normal    Created             pod/synthetic-5cc5f987df-nmcdk    Container created\n81s         Normal    Started             pod/synthetic-5cc5f987df-nmcdk    Container started\n81s         Normal    SuccessfulCreate    replicaset/synthetic-5cc5f987df   Created pod: synthetic-5cc5f987df-nmcdk\n81s         Normal    ScalingReplicaSet   deployment/synthetic              Scaled up replica set synthetic-5cc5f987df from 0 to 1\n81s         Normal    Scheduled           pod/web-86cc98785b-798hl          Successfully assigned shop/web-86cc98785b-798hl to oncall-lab-control-plane\n81s         Normal    Pulled              pod/web-86cc98785b-798hl          Container image \"nginx:1.29-alpine\" already present on machine and can be accessed by the pod\n81s         Normal    Pulled              pod/api-7d87b9fcf5-qp22z          Container image \"python:3.13-alpine\" already present on machine and can be accessed by the pod\n81s         Warning   Unhealthy           pod/web-86cc98785b-798hl          Readiness probe failed: Get \"http://10.244.0.191:80/healt","more":18},{"t":3.8,"kind":"run","cmd":"kubectl -n shop logs deploy/worker --tail=200 --timestamps=true","out":"2026-11-04T15:36:15.020357207Z worker started, batch buffer 64 MiB","more":0},{"t":7.3,"kind":"run","cmd":"kubectl -n shop get configmap api-code -o yaml","out":"apiVersion: v1\ndata:\n  api.py: |\n    import os, socket, sys, json, time\n    from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer\n    host = os.environ.get(\"DB_HOST\")\n    port = int(os.environ.get(\"DB_PORT\", \"5432\"))\n    if not host:\n        print(\"FATAL: DB_HOST is not set; check ConfigMap api-config\", flush=True)\n        sys.exit(1)\n    def db_ok():\n        try:\n            with socket.create_connection((host, port), timeout=1.0):\n                return True\n        except OSError as e:\n            print(f\"ERROR db connect {host}:{port}: {e}\", flush=True)\n            return False\n    class H(BaseHTTPRequestHandler):\n        def log_message(self, *a): pass\n        def send(self, code, body):\n            b = json.dumps(body).encode()\n            self.send_response(code); self.send_header(\"Content-Type\", \"application/json\")\n            self.send_header(\"Content-Length\", str(len(b))); self.end_headers(); self.wfile.write(b)\n        def do_GET(self):\n            if self.path == \"/healthz\":\n                return self.send(200, {\"ok\": True})\n            if self.path.startswith(\"/orders\"):\n                if db_ok():\n                    return self.send(200, {\"orders\": [{\"id\": 1, \"total\": 42}]})\n                return self.send(503, {\"error\": \"database unavailable\"})\n            if self.path == \"/jobs\":\n                return self.send(200, {\"jobs\": [{\"id\": int(time.time())}]})\n            self.send(404, {\"error\": \"not found\"})\n    print(f\"api listening on 8080, db={host}:{port}\", flush=True)\n    ThreadingHTTPServer((\"\", 8080), H).serve_forever()\n  worker.py: |\n    import os, time, urllib.request\n    mb = int(os.environ.get(\"BATCH_MB\", \"64\"))\n    print(f\"worker started, batch buffer {mb} MiB\", flush=True)\n    while True:","more":19},{"t":7.3,"kind":"run","cmd":"kubectl -n shop logs worker-76c6c9f7d-mqjjt --previous --timestamps=true","out":"unable to retrieve container logs for containerd://abcb54774788cbfdf821f2f68c0a4dc9601524d925ebfa9c102866a44e5ee130","more":0},{"t":7.3,"kind":"run","cmd":"kubectl -n shop rollout history deploy/worker --revision=1","out":"deployment.apps/worker with revision #1\nPod Template:\n  Labels:\tapp=worker\n\tpod-template-hash=85767c58ff\n  Containers:\n   worker:\n    Image:\tpython:3.13-alpine\n    Port:\t<none>\n    Host Port:\t<none>\n    Command:\n      python\n      -u\n      /app/worker.py\n    Limits:\n      memory:\t192Mi\n    Requests:\n      cpu:\t50m\n      memory:\t96Mi\n    Environment:\n      BATCH_MB:\t64\n    Mounts:\n      /app from code (rw)\n  Volumes:\n   code:\n    Type:\tConfigMap (a volume populated by a ConfigMap)\n    Name:\tapi-code\n    Optional:\tfalse\n  Node-Selectors:\t<none>\n  Tolerations:\t<none>","more":0},{"t":7.4,"kind":"run","cmd":"kubectl -n shop describe pod worker-76c6c9f7d-mqjjt","out":"Name:             worker-76c6c9f7d-mqjjt\nNamespace:        shop\nPriority:         0\nService Account:  default\nNode:             oncall-lab-control-plane/172.22.0.2\nStart Time:       Wed, 04 Nov 2026 15:35:33 +0000\nLabels:           app=worker\n                  pod-template-hash=76c6c9f7d\nAnnotations:      <none>\nStatus:           Running\nIP:               10.244.0.193\nIPs:\n  IP:           10.244.0.193\nControlled By:  ReplicaSet/worker-76c6c9f7d\nContainers:\n  worker:\n    Container ID:  containerd://686f0ca3b527611f9e1570b3049095def1b50ec22ff8b11a8777c877d7bd814d\n    Image:         python:3.13-alpine\n    Image ID:      docker.io/library/python@sha256:7984cf56ceaddebe4fefeb75d64000b9f45d8b77b11a09b24524da6cdc3af0c8\n    Port:          <none>\n    Host Port:     <none>\n    Command:\n      python\n      -u\n      /app/worker.py\n    State:          Terminated\n      Reason:       OOMKilled\n      Exit Code:    137\n      Started:      Wed, 04 Nov 2026 15:36:14 +0000\n      Finished:     Wed, 04 Nov 2026 15:36:15 +0000\n    Last State:     Terminated\n      Reason:       OOMKilled\n      Exit Code:    137\n      Started:      Wed, 04 Nov 2026 15:35:46 +0000\n      Finished:     Wed, 04 Nov 2026 15:35:47 +0000\n    Ready:          False\n    Restart Count:  3\n    Limits:\n      memory:  48Mi\n    Requests:","more":37},{"t":9.6,"kind":"say","text":"The worker is repeatedly OOM-killed: its 48 MiB limit is below its 64 MiB batch buffer. The previous deployment used a 192 MiB limit, so I’ll restore that limit within the runbook’s allowance."},{"t":9.7,"kind":"run","cmd":"kubectl -n shop set resources deployment/worker -c worker --limits=memory=192Mi","out":"deployment.apps/worker resource requirements updated","more":0},{"t":12.6,"kind":"run","cmd":"kubectl -n shop get pods -l app=worker -o wide","out":"NAME                      READY   STATUS    RESTARTS   AGE   IP             NODE                       NOMINATED NODE   READINESS GATES\nworker-5bf876c9cb-rwl42   1/1     Running   0          3s    10.244.0.194   oncall-lab-control-plane   <none>           <none>","more":0},{"t":12.6,"kind":"run","cmd":"kubectl -n shop logs deploy/worker --timestamps=true --tail=30","out":"2026-11-04T15:36:43.896181066Z worker started, batch buffer 64 MiB\n2026-11-04T15:36:43.929817091Z processed batch","more":0},{"t":12.6,"kind":"run","cmd":"kubectl -n shop rollout status deployment/worker --timeout=60s","out":"deployment \"worker\" successfully rolled out","more":0},{"t":17.6,"kind":"run","cmd":"kubectl -n shop get deployment worker -o jsonpath='{.spec.template.spec.containers[0].resources}'","out":"{\"limits\":{\"memory\":\"192Mi\"},\"requests\":{\"cpu\":\"50m\",\"memory\":\"48Mi\"}}","more":0},{"t":17.6,"kind":"run","cmd":"kubectl -n shop get pod -l app=worker -o wide","out":"NAME                      READY   STATUS    RESTARTS   AGE   IP             NODE                       NOMINATED NODE   READINESS GATES\nworker-5bf876c9cb-rwl42   1/1     Running   0          8s    10.244.0.194   oncall-lab-control-plane   <none>           <none>","more":0},{"t":17.6,"kind":"run","cmd":"kubectl -n shop get rs -l app=worker -o custom-columns=NAME:.metadata.name,CREATED:.metadata.creationTimestamp,REPLICAS:.spec.replicas","out":"NAME                CREATED                REPLICAS\nworker-5bf876c9cb   2026-11-04T15:36:43Z   1\nworker-76c6c9f7d    2026-11-04T15:35:33Z   0\nworker-85767c58ff   2026-11-04T15:35:16Z   0","more":0},{"t":17.6,"kind":"run","cmd":"kubectl -n shop logs deploy/worker --timestamps=true --tail=20","out":"2026-11-04T15:36:43.896181066Z worker started, batch buffer 64 MiB\n2026-11-04T15:36:43.929817091Z processed batch\n2026-11-04T15:36:48.960842933Z processed batch","more":0}],"report":"IMPACT: Worker jobs were delayed; the alert reported no batches processed for 10 minutes. The faulty rollout began at 15:35:33 UTC; the exact start of the delay is unconfirmed.\n\nROOT CAUSE: `Deployment/shop/worker` had `spec.template.spec.containers[worker].resources.limits.memory` set to 48 MiB, below its 64 MiB batch buffer. The worker was repeatedly OOM-killed.\n\nACTIONS TAKEN: Raised the worker memory limit to its previous value of 192 MiB.\n\nSTATUS: Resolved based on worker recovery: the rollout succeeded, the new pod was running with zero restarts, and logs showed two batches processed at 15:36:43 and 15:36:48 UTC. Alert clearance was not verified.\n\nESCALATION: None.\n\nFOLLOW-UP: Add a deployment check that ensures the worker memory limit accommodates its configured batch size."}