Hey guys, That might be a dumb question, but currently I find myself unable to clearly explain that to others. As we all know how CPU and memory is virtualised, and how memory address space is translated using the shadow page table or EPT, that creates each VM an individual running space. However, as each VM process is essentially an Linux process, how are they unable to do IPC among them? I tried to answer that question, but I was not confident about my explanation. Here's what I thought about. First, VMM like Xen or KVM supports virtualised OSes (paravirtualised or hardware-assisted virtualised). OS provides IPC mechanism but itself cannot use it to communicate with another OS. Although they run in guest machines which are essentially host's processes , they still cannot do IPC with others. Second, each VM process runs in an individual virtualised platform, it's the only OS running dominantly on its own virtualised resources, so it's unable to be aware of others. (But as each VM process has its PID, their processes have the potentials to do IPC if another one's PID is notified? ) Finally, the question can be described as, how does KVM enhance the process isolation to prevent those VM processes to IPC with each other? I also notice that KVM seems to be benefited from cgroups, is that contributing to the isolation? I hope someone could give me a perfect answer. However, any useful reply is appreciated. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
