CPU limit: an API slowed down on an idle machine
With --cpus=1, four threads use up the 100 ms CFS quota in 25 ms, then the whole container waits for the next period. Measured in Docker: an API's p99 goes from 7.5 to 78.7 ms while the container averages 0.25 CPU. Reading cpu.max and cpu.stat, and how to avoid the throttling.