The first problem is a speed, the second one is a security.
Generally microkernel more secure than monolithic-based operating system, but with some restrictions, if you grow up speed, you are loosing in security.
But it's a general problems - more complicated thing - we're using C/C++/ObjC to implement architecture, and there are language takes a many time and limits in the implementing.
My general idea is to use a functional programming language - and I've choose scheme - it's better, simply.
Look for the block diagram:
MuiString separated to the three logical parts, the first low two layers implemented on C (or on Cext in future), the third layer implemented on C/Cext and on scheme itself.
All hardware specific things are hidden in the MuiString.
All services should be implemented on scheme, yes, we're can use C-written servers and libs (it should be done for liblinux/libposix), but in general case all other will be implemented on scheme and ran on scheme VM.
All IPC will be operate via scheme forms - in this case all security models will be implemented without IPC calls restrictions, and it can be made on the VM (or language) level.
There are several security models and several objects on the higher level:
- Trusted servers
- Key signed
- Group politics
I will write more researching results in the next post.