alt Hacker NewsBuilding a swap device at user level used to be one of those classic unsolvable problems, because what if your daemon needs to swap in a page in order to swap in a page? Or at least it was discussed at a reason why microkernels will never work. I’m not sure what the solution is here.
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netbsdusers • today at 2:56 PM
The general principle is that what is involved in paging should not be paged itself. Wiring the memory of that whole daemon is then a trivial solution to the problem.
Your daemon can be smart enough to know which are its own pages and prevent them from being swapped out. The Linux kernel also prevents its own text pages from being swapped out, so the solution exists and I don’t see why it doesn’t apply to microkernel designs.