There are several emulated devices simply because there's no way around it (the rtc, PCI bus, uart, etc.). Obviously KVM handles a fair amount of emulation (PIT, IOAPIC) which is very nice.
Although the Linux implementation for 9p isn't great, there's nothing "fundamental" that limits the caching in the guest. For many use cases, you will have no shared mutable state in the host. Think docker: you have some shared read-only state, but the write bits are yours alone. You may cache anything freely.
This project was simply about playing with these ideas (and implementing a VMM using Go). You should check the slides out to understand the gap that I was looking at, but suffice to say I think there's a wide opportunity for something that gives you a process-like model but whose interface is that of a virtual machine. The key point is that you don't really want an ultra-quick "machine", you probably want to run a process ala Docker. I still want it to be contained as a VM however, for security and compatibility reasons.
Although the Linux implementation for 9p isn't great, there's nothing "fundamental" that limits the caching in the guest. For many use cases, you will have no shared mutable state in the host. Think docker: you have some shared read-only state, but the write bits are yours alone. You may cache anything freely.
This project was simply about playing with these ideas (and implementing a VMM using Go). You should check the slides out to understand the gap that I was looking at, but suffice to say I think there's a wide opportunity for something that gives you a process-like model but whose interface is that of a virtual machine. The key point is that you don't really want an ultra-quick "machine", you probably want to run a process ala Docker. I still want it to be contained as a VM however, for security and compatibility reasons.