What are “multikernel computers”?

Question

Which does the term 'modern multikernel computers' refer to? Distributed systems or multi-core computers?

I saw it in a one-line question, so no context to help! Google didn't help neither.

Answer 1

distributed systems or multi-core computers?

Both. It's something like treating a multicore computer like a distributed system.

The Multikernel approach is described in this paper by Andrew Baumann et al.: The Multikernel: A new OS architecture for scalable multicore systems (published by the ACM, 2009). You'll find every possible information there, but here are the most important parts from the abstract.

First, why is there are need for something like this?

Commodity computer systems contain more and more processor cores and exhibit increasingly diverse architectural tradeofs, including memory hierarchies, interconnects, instruction sets and variants, and IO configurations. Previous high-performance computing systems have scaled in specific cases, but the dynamic nature of modern client and server workloads, coupled with the impossibility of statically optimizing an OS for all workloads and hardware variants pose serious challenges for operating system structures.

Then, what is multikernel?

We argue that the challenge of future multicore hardware is best met by embracing the networked nature of the machine, rethinking OS architecture using ideas from distributed systems. We investigate a new OS structure, the multikernel, that treats the machine as a network of independent cores, assumes no inter-core sharing at the lowest level, and moves traditional OS functionality to a distributed system of processes that communicate via message-passing.

Finally, you can even try it. Barrelfish is a multikernel operating system, released under the MIT open source license, created by the ETH Zürich and Microsoft.

Related to this, yet a bit earlier, also by Andrew Baumann et al.: Your computer is already a distributed system. Why isn’t your OS?.