Limit the disk usage for each build

[yuichi10]

What happened:

I want to limit the disk usage for each build. If one user uses a lot of disk, it will affect other build pods. I would like to have a way to limit disk usage to prevent this problem.

What you expected to happen:

Add ephemeral-storage options to build pod yaml.

How to reproduce it:

Run build pod which use a lot of disk spaces.

[yuichi10]

The background is we try to use executor k8s dind function for docker build. At that time we will use containerd and Overlayfs. If we use containerd and devicemapper we can limit the disk usage by containerd config. However it looks like it is hard to limit the disk usage with containerd and Overlayfs.

It is the reason why I want this feature. At least I want to limit the dind container disk usage, but I think it is not bad to have feature to limit disk usage for generally pod.

Since this feature depends on what environment you use it in, it would be better to have a feature flag such as docker.enabled.