By using the -c (or --cpu-shares as an equivalent) for the docker run command switch, it's possible to specify a value of shares of the CPU that a container can allocate. By default, every new container has 1024 shares of CPU and all containers get the same part of CPU cycles. This percentage can be altered by shifting the container's CPU share weighting relative to the weighting of all other running containers. But take note, that you cannot set the precise processor speed that a container can use. This is a relative weight and has nothing to do with the real processor speed. In fact, there is no way to say precisely that a container should have the right to use only 2 GHz of the host's processor.