I do not know much about kernels and OS architecture. But I am wondering how this relates to the idea of GNU Hurd. Wasn't its concept also about microkernel-based design?
This is pretty different, Hurd ran all of this stuff in user space.
It's really close to exokernels though. XOK had three different, but similar VMs for running user code in kernel space. Like their version of futex was a filter program that got run to see if the program should be woke up.
