Cardinality & cost rules

Telemetry cost is mostly cardinality, and cardinality is mostly one label somebody added without thinking. This tab is where you find it and where you fix it.

What it shows

• Cardinality by metric and by label — the series count each one is responsible for, ranked. The top of that list is usually a request id, a pod name, or a user id that became a label.
• Per-series drill-down, so you can see the offending values before you act.

Three rule families

Rules	What they do
Reduction rules	Drop or aggregate away series and log lines you do not need.
Parsing rules	Extract structure from unstructured log lines so they become searchable fields instead of text.
Sensitive-data rules	Redact values before they are stored.

Reduction rules are also surfaced on the Logs tab, so a search that returns nothing shows you which rule may be the reason.

Caution

A reduction rule is a decision about what you will not be able to ask later. Data dropped at ingest is not recoverable — write the rule narrowly, and check the volume it claims before enabling it.

Usage & Savings

The left rail’s Usage & Savings page rolls the same numbers up per signal — traces, metrics, logs — against the plan’s ingest allowances, and attributes savings to the rules that produced them.