Agent WranglersINF-72Recommended
Track cost per request
Divide each service's monthly cost by the work it did, such as cost per 1,000 requests or per active customer. Send each owning team its own figures every month, and alert when a unit cost rises more than 20% from the month before.
How to do it
Total cost grows with traffic, which is expected. A rising cost per unit means scaling went wrong, such as an autoscaler that never scales down or a cache that misses. Watch what the service costs tracks the totals and tags. Take the request counts from rate, errors and duration. Show the unit cost on the service dashboard, and compare it before and after each scaling change. Group the bill by the owner and service tags from Tag every resource with its owner. Split shared costs, such as a cluster, by a written key such as CPU hours. A monthly report to each team, without charging them, is called showback. It makes each team see what its own choices cost.
How to check
A monthly report shows the cost per 1,000 requests for each service and goes to the team in its owner tag. Shared costs in the report add up to the shared bill within 5%. An alert fires when a unit cost rises more than 20% from the month before.
Sources
Related rules
- INF-53 Give every account a budget with alerts in Infrastructure and environments
- OPS-12 Measure rate, errors and duration in Operations and observability
- OPS-16 Give each service one dashboard in Operations and observability
- INF-52 Tag every resource with its owner in Infrastructure and environments
- INF-69 Track carbon per request beside cost in Infrastructure and environments
- USG-11 Charge each model call's cost to the customer who caused it in Usage-based billing
- TDD-14 Measure cost per customer over the last 12 months in Technical due diligence
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