minikube: "minikube image save" is extremely slow

What Happened?

I’m trying to backup (over local host) some docker images that take hours to build (not images of mine; I have no way to reduce that). This because I want to minikube delete and then restore everything, removing the re-build time.

Running

cd /mini-backup/
minikube image save myimage:mytag myimage_mytag.tar

works… …but takes so long to complete.
Is the command supposed to be that slow?
Should I expect the same slowness also when putting the images back with minikube image load?

The whole reason I was trying to backup & restore images, was to be able to delete the VM and come back to productivity quickly.
But with these timings the strategy doesn’t really serve, and I might well delete and rebuild everything from scratch.

Am I doing something wrong?
How can I take the images out of Minikube to restore them afterwards? (in decent times)

Additionally:

• I could run a local repository that stores in a local volume mount, but that would require renaming the repository name everywhere in my codebase in order to interface with it.
• just in case, yes, I’m using Virtualbox & no, I can’t switch to hyperkit.

Attach the log file

[log contains too much private data; and is not relevant here: eventually ask for specific info from it]

Operating System

macOS (Default)

Driver

VirtualBox