Observability Practical By Samson Tanimawo, PhD Published May 18, 2026 4 min read

The Trace Attribute Cost Model

Each attribute on a span costs storage. The model, the budget, and the high-value attributes that pay their keep.

The cost model

Each attribute key/value adds bytes to every span. Multiply by spans per second; that is the cost.

1 KB attribute × 1000 spans/sec × 30 days = ~2.5 TB. Real money.

10-15 attributes per span. Above that, decide what to drop.

Critical attributes: standard semconv (HTTP, RPC, K8s). Custom attributes: only the ones used in queries.

Quarterly: review attribute usage. Attributes not queried in 90 days are candidates for removal.

Most teams find 30-50% reduction is safe.