Unable to use --cpus for docker run

hello,
i was trying out the following blog in order to learn resource management in docker:
https://goldmann.pl/blog/2014/09/11/resource-management-in-docker/#_cpu
I’m unable to run the following command:
docker run --rm busybox:latest --cpus 0.4

Error:
container_linux.go:247: starting container process caused "exec: “–cpus”: executable file not found in $PATH"
docker: Error response from daemon: oci runtime error: container_linux.go:247: starting container process caused “exec: “–cpus”: executable file not found in $PATH”.

docker version:

Client:
Version: 17.03.1-ce
API version: 1.27
Go version: go1.7.5
Git commit: c6d412e
Built: Mon Mar 27 17:05:44 2017
OS/Arch: linux/amd64

Server:
Version: 17.03.1-ce
API version: 1.27 (minimum version 1.12)
Go version: go1.7.5
Git commit: c6d412e
Built: Mon Mar 27 17:05:44 2017
OS/Arch: linux/amd64
Experimental: false

System: centos 7

Thank you. :slight_smile: