Paravirtualization is a virtualization technique in which the kernel of the guest OS 'cooperates' with the hypervisor in providing low-level hardware-related functions, instead of relying on slower and much more complex emulation. This requires a modified kernel of the guest OS.
I am trying to setup a server where I would be running multiple apps. Mostly internal but could also be open source projects like Redmine. They would all be Rails/Ruby apps/test scripts running on ...