[Oberon] Oberon V4 on the Raspberry Pi?
joerg.straube at iaeth.ch
Mon Jan 11 18:24:05 CET 2021
It's all a question of definition aka wording__
There two kind of hypervisors
- type-1 (or native) hypervisor: the hypervisor is totally independent of an OS, provides own HW drivers --> Xen, VMware ESX..
- type-2 (or hosted) hypervisor: the hypervisor uses HW drivers provided by the Host OS/Kernel --> KVM (needs Linux), Hyper-V (needs Windows), Parallels for Mac (needs macOS)..
Type-1 hypervisors need a full reinstallation as they provide own HW drivers independent of a Kernel/Host OS.
Type-2 hypervisors can be added later without an OS re-installation, as they use the HW drivers of the Kernel/HostOS. Performance depends on the hypervisor's capability to use the virtualization feature provided by the HW if any. A hypervisor can work without these HW accelerators.
Let's have a closer look into Linux: KVM almost always comes with QEMU. As the name says: QEMU is a "quick emulator".
- QEMU provides all the "virtualized" resources like network card, graphics card and so on.
- QEMU also has to provide "virtualized" CPUs and can even translate instruction sets if needed. In case you add the KVM module to your kernel, QEMU will use KVM for its task "CPU virtualization". You can see KVM as kind of accelerator for QEMUs "CPU virtualization". That's the reason why earlier "qemu -enable-kvm" became "qemu -accel=kvm"
So, what you call "virtualized" in your earlier post will Linux provide with a SW named "quick emulator" __
More information about the Oberon