Greater than 100% CPU utilization is not documented

[SmitaPatankar]

Steps to Reproduce:

• Create a container that needs high CPU utilization at times, but limit the "cpus" for it.
• Run the container.
• Run this command in while loop in shell script and print output to some file.
  check_docker --connection /var/run/docker.sock --containers all --cpu 80:95

My Setup:

• My server has 2 CPUs.
• My container needs high CPU utilization at start because of many supervisor services getting auto started at once, but I have limited the "cpus" to "0.75".

Output at times, initially:

CRITICAL: {containername} cpu is 103%
|{containername}_cpu=103;80;95;0;100

Reason behind the output:
It seems that when CPU utilization exceeds the limit slightly, it gets under control i.e. there is some margin.

Additional logs:

docker inspect {containername}|grep -i cpu
            "CpuShares": 0,
            "NanoCpus": 0,
            "CpuPeriod": 100000,
            "CpuQuota": 75000,
            "CpuRealtimePeriod": 0,
            "CpuRealtimeRuntime": 0,
            "CpusetCpus": "",
            "CpusetMems": "",
            "CpuCount": 0,
            "CpuPercent": 0,

Issue: The documentation(README file) only talks about the values from 0-100, not beyond that.
In this case, we should ideally set the warning:critical to something like 110:125 instead.

[timdaman]

Hmm, that is an issue I had not considered. Thanks for sharing.

I just want to ensure my change makes sense to you. All I am doing is updating the help string and documentation to remove the suggestion of a 0-100% range. That seems like it should be enough as well as being a bit more accurate since I do allow values bigger than 100.

Does that sound right to you?

[SmitaPatankar]

Yes, sounds good. Thanks.