Monitoring Metrics Reference

✅ Fresh -- Updated March 2026 from official Google Cloud documentation.

Complete reference for all API monitoring metrics available in Cloud Monitoring.

API Request Metrics

All metrics use the prefix serviceruntime.googleapis.com/.

Metric	Type	Description	Labels
api/request_count	Delta / Int64	Total number of API requests	response_code, response_code_class, protocol, api_method
api/request_latencies	Delta / Distribution	Request latency in milliseconds	response_code, api_method
api/request_sizes	Delta / Distribution	Request payload size in bytes	api_method
api/response_sizes	Delta / Distribution	Response payload size in bytes	api_method

Quota Metrics

Metric	Type	Description	Use
quota/allocation/usage	Gauge / Int64	Current allocation quota consumed	Track long-term quota usage
quota/rate/net_usage	Delta / Int64	Current rate limit consumption	Track per-minute/second limits
quota/limit	Gauge / Int64	Configured quota limit	Compare with usage for headroom
quota/exceeded	Delta / Int64	Number of times quota was exceeded	Alert on exhaustion

Metric Labels

response_code

The HTTP status code of the response (e.g., 200, 404, 500).

response_code_class

Grouped HTTP status classes:

Class	Meaning
2xx	Success
3xx	Redirect
4xx	Client error
5xx	Server error

api_method

The specific API method called (e.g., google.pubsub.v1.Publisher.Publish).

protocol

The protocol used: http, grpc.

Example Monitoring Queries

Request Rate (MQL)

fetch consumed_api
| metric 'serviceruntime.googleapis.com/api/request_count'
| align rate(1m)
| every 1m
| group_by [resource.service], [value_request_count_aggregate: aggregate(value.request_count)]

Error Rate Percentage

fetch consumed_api
| metric 'serviceruntime.googleapis.com/api/request_count'
| filter (metric.response_code_class = '4xx' || metric.response_code_class = '5xx')
| align rate(1m)
| every 1m
| group_by [resource.service], [value_request_count_aggregate: aggregate(value.request_count)]

P99 Latency

fetch consumed_api
| metric 'serviceruntime.googleapis.com/api/request_latencies'
| align delta(1m)
| every 1m
| group_by [resource.service], [value_request_latencies_percentile: percentile(value.request_latencies, 99)]

Quota Usage vs. Limit

fetch consumer_quota
| metric 'serviceruntime.googleapis.com/quota/allocation/usage'
| group_by [resource.service, metric.quota_metric], [value_usage: aggregate(value.usage)]

Metrics Explorer Usage

Access Metrics Explorer in the Cloud Console:

https://console.cloud.google.com/monitoring/metrics-explorer?project=PROJECT_ID

Steps to View API Metrics

1. Open Metrics Explorer
2. Set Resource type to Consumed API
3. Set Metric to Request count (or latencies, sizes)
4. Add Filters (e.g., service = storage.googleapis.com)
5. Set Aggregation to Sum or Rate
6. Adjust Time range as needed

Dashboard Widgets

Recommended dashboard layout:

Alert Thresholds (Recommended)

Metric	Condition	Threshold	Duration
Error rate	> percentage	5%	5 minutes
p99 latency	> value	2000ms	10 minutes
Quota usage	> percentage of limit	80%	Instant
Traffic drop	< percentage of baseline	50%	15 minutes
Zero traffic	= value	0 requests	30 minutes

See Also

• Monitoring Workflow -- How to set up monitoring end-to-end
• Troubleshooting -- Using metrics to diagnose issues
• Error Codes -- Error code details