This is a concept that doesn't even exist in most other systems, so there isn't an agreed name for it (we call it a "slice" in Spyre). It's similar to a Kubernetes "pod" but not quite.
https://getcarina.com/docs/faq/ has more
I don't care how many devices/segments/nodes/slices/dynos/widgets are in my cluster. I care that I have X GB of total memory and Y cpu's. I want to check a box to make an app or service highly available (on more than one node, and in more than one zone) and Ronco™ set it and forget it.
Everything else is just noise.
I love the ideas behind Kubernetes and Fleet/CoreOS (and this) but everyone is SO excited about these low level technologies that have yet to be composed into beautiful experiences.
A tweet from Kelsey Hightower sums it up perfectly:
It's going to be nearly impossible for people
to evaluate and chose a container management platform
during the gold rush.