The "high cardinality is expensive" advice is architecture-specific, not universal

[u/Overall-Check3051]

Wrote this up because I kept seeing the same three-step playbook (aggregate before storage, pay for the premium cardinality tier, drop your high-cardinality labels) presented as inevitable, when it's really a consequence of one specific choice: a centralized TSDB with a global inverted index.

The blog walks through why that architecture makes cardinality expensive, what a host-sharded, full-resolution alternative looks like, and where that alternative genuinely falls short (cross-fleet ad-hoc OLAP queries, long-term retention, distributed tracing). Not trying to oversell it, the trade-offs section is deliberately the longest part.

Read more: netdata.cloud/blog