New snapshot: network stack cloning / virtualization patches

[Marko Zec]

Network stack cloning patches allow for multiple fully independent network 
stacks to simultaneously coexistst in a single FreeBSD kernel. Combined with 
jail-style separation between user processes and with proportional-share 
extensions to the standard BSD CPU scheduler, the patched kernel can 
efficiently provide isolated and controllable pseudo virtual machine 
environments. The patches preserve the userland to kernel API/ABI, so all 
existing applications can run on the patched kernel without any need for 
modifications / recompiling.

The latest snapshot of the patches (against 4.8-RELEASE) can be found at
http://www.tel.fer.hr/zec/vimage/

What's new:

Internal restructuring - struct vimage is now separated in resource-specific 
containers for network stack (vnet), jail-style process group (vprocg), and 
CPU scheduling (vcpu). This should allow for more modular resource 
virtualization in the future, however the necessary management API has yet to 
be implemented;

Kernel message buffers - each vimage / vprocg now has a private kernel message 
buffer instance, thus allowing for (virtualized) printf() and log() messages 
from within the kernel to be routed to the appropriate msgbuf. The /dev/log 
interface has been hacked to support for multiple syslogd instances to access 
it simultaneously, while each receiving only the messages from the 
appropriate msgbuf instance;

Several important bugfixes in TCP code virtualization.


Cheers,

Marko