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Comment by yebyen | Hacker News Reader

> That minimal quality of most of the OS not being present also explains why the container the drivers run in is called a rump kernel

I have seen a number of articles on 'rump' kernels and they always similarly gloss over the name like this. How does that explain? It's not capitalized, so I assume it is not an acronym that stands for something.

Where does this name come from? Is it an acronym, portmanteau, metaphor, what? I have never seen it clearly explained, and I have followed link trails down the rabbit hole through circular references and wikis looking, half a dozen times at least, to no avail.

Can someone please clue me in?

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When you don't know what a word means, the best place to start looking is usually a dictionary. For example, Merriam-Webster's definition 3:

  a small or inferior remnant or offshoot; especially :  a group 
  (as a parliament) carrying on in the name of the original body 
  after the departure or expulsion of a large number of its
  members

http://www.merriam-webster.com/dictionary/rump

> Where does this name come from? Is it an acronym, portmanteau, metaphor, what?

It appears to be a fairly standard use of the English word "rump" in its non-anatomical sense, that is "a small or unimportant remnant of something originally larger."

The classic use is to talk about the Rump Parliament of 1648 in England: https://en.wikipedia.org/wiki/Rump_Parliament

You win the gold star, that was the historical context of this usage of the word that I did not understand and what I was missing, mystery solved. Thank you!

"An anykernel can be instantiated into units which virtualize the bare minimum support functionality for kernel drivers. We call these virtualized kernel instances rump kernels since they retain only a part of the original kernel."

Page 33, http://lib.tkk.fi/Diss/2012/isbn9789526049175/isbn9789526049...

This is an example of canonical documentation doing exactly the same thing I just described. I am no more enlightened about what a "rump kernel" is than before I read the paragraph.

Is the implication that we're tossing out the head, neck, loins, bones, organs, etc. and only the delicious bacon of the original kernel is kept? The rump is the part?

Yes, the rump (of the) kernel.

Never mind, answered my own question with a little more search query skill:

Runnable Userspace Meta Programs

I'm going to bet that is a backronym.

If I had to guess, I would go with the idea that you don't need the whole (OS) beast, just its hindquarters (the rump). But don't quote me.

(Re: your subsequent comment: Yeah, just the bacon.)

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