Require minimum available disk space before starting job?

I’m seeing transient build failures on due to “no space left on device”. This seems to happen when I have many concurrent executions. (The total size of the git repository + all of the dependencies installed during execution is somewhere around 15 GB.)

1). Is there a way to configure it to avoid this problem? E.g. each execution “reserves” the amount of disk space it needs?

2). What’s the right mental model to use for how servers manage their disk space? Does it fully clean up all disk space used during a build (containers, volumes, etc.), or is there a chance that artifacts would accumulate somehow?

3). I’m assuming multiple builds can be run concurrently on one instance, but can builds from two different repositories / accounts share a machine? Or are my builds only competing for disk space with each other?

We are exploring a bring-your-own server model which would give you the ability to hook up your own reserved instance to Drone Cloud.