The performance for my workers at the 99th and 99.9th percentile seems to sometimes exceed 50ms and, according to the chart in the Cloudflare dashboard, even goes as high as 150ms. Even though that’s the case, I haven’t had a single “Exceeded resources” error.
After doing some performance testing with Workers to try and find the culprit (by just deploying differing versions and testing each one), I came across Metrics | Cloudflare Workers in the Cloudflare Workers docs. It states:
In some cases, higher quantiles may appear to exceed CPU time limits without generating invocation errors because of a mechanism in the Workers runtime that allows rollover CPU time for requests below the CPU limit.
It feels like this might be the case with my workers, but I’m not sure what this paragraph means.
What’s “rollover CPU time”? Does this mean that my workers are actually doing the work in <50ms?