ucsdets/k8s-support repository overview

⁠k8s-support

This container is run before our main notebook server container.

Mounts the bin directory in this repo into /opt/k8s-support; see https://github.com/ucsd-ets/dsmlp-helmfile/blob/master/releases/jupyterhub/extraConfig.py⁠:

• c.KubeSpawner.volume_mounts
• c.KubeSpawner.singleuser_init_containers

we are using tini package from https://github.com/krallin/tini⁠. tini run as init process and create sub process like jupyter notebook etc. why we use tini? when application creates child process and if child process gets terminated the parent needs to wait on the child process to call wait operation to clear the child process from the process table. But in docker this doesn't happen usual so tini is small package which reaps the orphan child process.

Screen command is helpful when we want to connect with process which is running in background. For example when we have job which take day to complete in this case we can use screen. screen help us connect and disconnect from the terminal of the background process. more info https://www.gnu.org/software/screen/manual/screen.html#Screen-Command⁠ most common use case:
$ screen :- this will create new process
$ screen ls :- will all the screen process that are running in background
$ screen -r pid :- Used to attach to the background process
$ screen -d pid :- Used to de attach the process from the terminal

Pause command run a process with sleep and process gets killed by receving the sigterm command. pause command is used to when the conainer is run and waiting until the user connect to container. We are building the docker from the google/pause which has pre built pause command. we are moving into the bin folder.