Are there security benefits? Probably. Better performance? Could be. But why did they come up with their solution? What about differences with other Unikernel approaches? I mean its a research lab, not a hobby project.
To answer your question:
> Better performance? Could be.
That's one aspect. If you follow the link from the Clive page to its predecessor Nix[3], its tagline is "high performance cloud computing is nix". A current (2018) justification for that project can be found in the form of an abstract for a paper with the same name[4].
But then the other part is given away in the abstract for Clive itself: "Clive introduces new file system technology and novel interfaces for the construction of networked system"[5], which is another way of saying that this is blue sky research, which is itself a codeword for we decided to try out a bunch of things purely _because_ they're different and want to see if anything will come out of it. Notice how the screenshot here shows the OS shell is some sort of acme-like[6] made to run in a web browser, for example.
To repeat my earlier remark, the author's other pages are well worth a look. For example, don't miss this[7] page chock full of links to research OSes (although many of them are dead). Or there's Picky[8], which looks like what you'd get if you took Pascal/Oberon and more or less did a transliteration so that the grammar gives you a curly brace language instead of a wordy, shouty one with BEGIN, END, etc.
1. https://news.ycombinator.com/item?id=16253193
2. http://lsub.org/ls/nix.html
3. http://lsub.org/ls/nix.html
4. http://lsub.org/ls/nixbltjabs.pdf
5. http://lsub.org/export/clivesys.pdf
6. http://syssoftware.blogspot.com/2016/02/clives-ink-screensho...
- [1] https://jisajournal.springeropen.com/articles/10.1186/s13174...