How to get cpu and memory information from docker container

[kwon14]

Hello. Thank you so much for providing a good extension.

I am using Jupyterlab with ubuntu docker running.
To use jupyterlab-system-monitor, you need to set the number of CPU cores and memory capacity allocated to the container,
but I can't figure out how to get that information.

Please share how to get cpu and memory information in the container.

thank you.

[dleen]

Hi,

For memory, depending on your distribution, you can find this information via cgroups in the file: /sys/fs/cgroup/memory/memory.limit_in_bytes. For my container I get the following (using a quick Python script to convert to MiB):

cat /sys/fs/cgroup/memory/memory.limit_in_bytes | python -c 'import sys; print(int(sys.stdin.readlines()[0].strip())/1024/1024)'
16384.0

which shows 16384MiB or 16GiB as the limit.

CPU is much more difficult. You might be able to do something similar via some file in /sys/fs/cgroup/cpu but unlike memory CPU usage is relative to other processes/containers. It would be better if you could pass the value you pass to Docker --cpus as an environment variable and read that from inside the container.