Should your services push metrics to a collector, or should the collector pull metrics from your services? Sounds like a minor detail. It changes your entire monitoring architecture.

You’re storing metrics at 1-second granularity. After a year, that’s 31 million data points per metric. Nobody looks at second-level data from 6 months ago. But you still need the trends.

Your monitoring system ingests 100,000 metrics per second. Each is a timestamp, a name, and a value. A regular database buckles. Time-series databases are designed for exactly this shape of data.