[shitloadofbooks]

We went from Prometheus (bursting at the seams and begging to be scaled) -> a failed Cortex implementation -> a rock solid Victoria Metrics implementation.

We found Cortex to be extremely over-engineered, extremely hard to tune (because of multiple configuration/argument refactors with incomplete doc cleanups) and found that it would just fall over under load. (Though to be fair, there wasn't much in the way of first-party deployment tooling at the time, so it was a hand-rolled Helm chart and at least 50% of the issues were likely my config).

In comparison, the first-party Victoria Metrics Helm chart worked straight out of the box, the maintainers have fixed multiple small issues within hours of me reporting them and we've thrown an extremely large amount of metrics at it with zero problems.