This tutorial describes how to limit CPU usage in Ubuntu 18.04 LTS. I will use CPU-limit utility for this purpose. Cpulimit is a tool which limits the CPU usage of a process (expressed in percentage, not in CPU time). It is useful to control batch jobs when you don’t want them to eat too many CPU cycles. The goal of cpulimit is to prevent a process from running for more than a specified time ratio. It does not change the nice value or other scheduling priority settings, but the real CPU usage.