Puts applications in control, runs 10x or more faster. Exopc and XOK versions run on x86 PCs. ExOS library gives user-level extensible implementation of Unix OS, so most applications compile and run with no change. Download. [Open Source, MIT] http://www.pdos.lcs.mit.edu/exo.html
Traditional OSs limit application performance, flexibility, functionality by fixing interfaces and implementations of OS abstractions such as interprocess communication and virtual memory. Exokernel address this via application-level management of physica http://citeseer.ist.psu.edu/engler95exokernel.html
Makes µnOS: 72k microkernel on 8k nanokernel client/server architecture based on OOP framework, symmetric multithreading, multitasking, priority based scheduling, fully interruptible, separated address spaces, and full memory protection. Free download. http://www.miray.de/home/
Claimed as radical new approach to OSs: no-kernel, self-modifying cells (like objects); single address space, useful where memory and CPU power is low, and maybe for AI. Written in self-modifying, modular assembly language. [Open Source, BSD] http://uuu.sourceforge.net/
Main idea: enforce no abstractions, rather, have them as options, to all levels of system: hardware, kernel and file services, ways users interact with system; based on exo principles. Descriptions, news. [Open Source] http://elysium.sourceforge.net/