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With the elastic CPU limiter (#86638) closely tracking acquired/returned CPU nanoseconds, it's possible to compute what % CPU utilization it's nominally overseeing. In experimentation we've been using prometheus/grafana (https://gist.github.com/irfansharif/3174555485931f8ae6e723ab9f2d3573 for ex.) where this CPU % is being computed using:

(rate(admission_elastic_cpu_acquired_nanos[$__rate_interval]) - rate(admission_elastic_cpu_acquired_nanos[$__rate_interval])) / admission_elastic_cpu_max_available_nanos

This timeseries math is not possible in CRDB natively. But it's a useful one to export directly to observe the limiter in action. We could compute this similarly within CRDB and export as a metric.

+cc @cockroachdb/admission-control.

Jira issue: CRDB-20453