Tor has a bunch of weird bugs when it runs out of disk space. One of the crazy ones that has been driving us mad for more than a decade is that relays somehow decide to start publishing a new descriptor once per second, forever. Can we make a version of the unit tests where all of the disk interactions act like the disk is full? Can we make a version of the chutney network tests where the disk pretends to be full? This idea seems like a great one to add to our testing toolbelt.