PCD Managing application performance monitoring — All Questions With Answers

Refer to the exhibit.

Cloud Trace details for a single request:
```
Span ID: 0000000000000001
Service: frontend
Duration: 1200ms
   Child Spans:
     - Span ID: 0000000000000002, Service: auth, Duration: 800ms
     - Span ID: 0000000000000003, Service: productcatalog, Duration: 300ms
     - Span ID: 0000000000000004, Service: recommendations, Duration: 50ms
```

Refer to the exhibit.

Cloud Monitoring Metrics Scope:
- Project: prod-project
- Metrics: 
  - latency | resource.type="gae_app" | resource.labels.module_id="frontend" | metric: custom.googleapis.com/opentelemetry/request_latency
- Alert Policy ID: 123456789
- Condition: metric.threshold > 500 ms for 1m
- Notification Channels: email (dev-team@example.com), PagerDuty

Cloud Logging Log Entry (from frontend service):
{
  "textPayload": "Request processed",
  "severity": "INFO",
  "httpRequest": {
    "requestUrl": "https://frontend.example.com/api/checkout",
    "status": 200,
    "responseSize": "2048",
    "latency": "0.452s"
  },
  "resource": {
    "type": "gae_app",
    "labels": {
      "module_id": "frontend",
      "version_id": "v2"
    }
  }
}

fetch gce_instance
| metric 'compute.googleapis.com/instance/cpu/utilization'
| group_by [zone], 1m [mean_cpu: mean(value.cpu_utilization)]
| every 1m
| condition mean_cpu > 0.8

{
  "insertId": "abc123",
  "severity": "ERROR",
  "resource": {
    "type": "gce_instance",
    "labels": {
      "instance_id": "1234567890",
      "zone": "us-central1-a"
    }
  },
  "jsonPayload": {
    "message": "Connection refused: connect to 10.0.0.1:8080",
    "service": "backend"
  }
}

alertingPolicy:
  displayName: "Error Rate Alert"
  conditions:
  - displayName: "Error rate > 1%"
    conditionMonitoringQuery:
      query: "fetch cloud_run_revision::run.googleapis.com/request_count | { filter response_code_class > 500 ; group_by [], sum() } / { group_by [], sum() } | condition gt 0.01"
    thresholdValue: null
    duration: 0s

fetch gce_instance
| metric 'compute.googleapis.com/instance/cpu/utilization'
| filter metric.utilization > 0.9
| align mean(5m)
| every 5m

{
  "insertId": "1a2b3c",
  "jsonPayload": {
    "message": "Request completed",
    "latency_ms": 150,
    "status": 200,
    "trace": "projects/my-project/traces/abc123"
  },
  "resource": {
    "type": "gce_instance",
    "labels": {
      "instance_id": "12345",
      "zone": "us-central1-a"
    }
  },
  "severity": "INFO",
  "timestamp": "2024-01-01T12:00:00Z"
}

combiner: OR
conditions:
- conditionThreshold:
    filter: resource.type = "gae_app" AND metric.type = "appengine.googleapis.com/http/server/response_count"
    aggregations:
    - alignmentPeriod: 60s
      perSeriesAligner: ALIGN_RATE
    conditionValue:
      value: 10
    duration: 300s
    trigger:
      count: 1

Refer to the exhibit. The following alerting policy is defined:
{
  "displayName": "High Error Rate",
  "condition": {
    "conditionThreshold": {
      "aggregations": [
        {
          "alignmentPeriod": "60s",
          "crossSeriesReducer": "REDUCE_SUM",
          "perSeriesAligner": "ALIGN_RATE"
        }
      ],
      "filter": "metric.type=\"logging.googleapis.com/user/error_count\" resource.type=\"gke_container\"",
      "duration": "300s",
      "comparison": "COMPARISON_GT",
      "thresholdValue": 10,
      "trigger": {
        "percent": 100
      }
    }
  }
}

Refer to the exhibit. Below are Trace spans from a sample request:
Span 1: /checkout (300ms) -> Span 2: validateCart (100ms) -> Span 3: processPayment (150ms) -> Span 4: sendConfirmation (50ms)

Refer to the exhibit. The following error group is shown in Cloud Error Reporting:
Exception: java.lang.NullPointerException
at com.example.OrderService.checkout(OrderService.java:45)