XEN virtualization on iWave’s i.MX8QM System on Module
iWave Systems, a leading embedded solutions provider company based in Bangalore has successfully demonstrated Xen virtualization hypervisor on their i.MX8 QM SoC based System on Module. The multi-core SOM comprises of 2x Arm® Cortex®-A72 @1.8 GHz and 4x Arm® Cortex®-A53 @1.2 GHz and 2x additional Cortex®-M4F @ 266 MHz, rendering a highly powerful integrated solution on a SMARC R2.0 compatible module.
To fully explore the enormous computing capability of the i.MX8 QM SOM, iWave has implemented virtualization of hardware using the open source type 1 Xen hypervisor. The Xen hypervisor enables multiple virtual machines to be created over a single hardware resource, each virtual machine capable of running its own independent operating system. This enables the i.MX8 QM SOM run multiple operating systems concurrently on the same physical board. The Xen hypervisor allows maximum utilization of resources thereby improving overall system performance and efficiency.
About Xen hypervisor
Xen is an open source type-1 hypervisor developed by the University of Cambridge and is now being developed by the Linux Foundation. Xen runs directly on the hardware to manage guest operating systems. Hence, it's also considered as a bare metal hypervisor. Xen has less overhead enabling faster performance and Operating Systems are more secure as they don't rely on base OS for installing the hypervisor.
A system running the Xen hypervisor contains three components:
- Xen Hypervisor
- Domain 0 (Dom0) – Privileged virtual machine running on the hypervisor that can access the hardware directly and interact with other unprivileged virtual machine running on the system.
- Multiple DomainU (DomU) – Unprivileged virtual machine running on the hypervisor and have no direct access to hardware (e.g. CPU,memory, timer and interrupts cannot be directly accessed)
During the initial system start-up, Xen hypervisor launches the Dom0 that runs the Linux operating system. The Dom0 has unique privileges to access the Xen hypervisor compared to other Domains. Dom0 manages the DomU, the unprivileged domains running on the system. Dom0 allocate and map hardware resources for the DomU domains.
- Less overhead compared to type-2 hypervisors since type-1 hypervisors make use of ARM virtualization extensions.
- Having faulty/buggy OS in DOM-U domain will not disrupt the functionalities of DOM-0 OS.
- DOM-U driver domains can support legacy hardware drivers no longer supported by new OS.
- Have completely isolated workspaces with different requirements. Eg: gaming and multimedia.
- Better resource management since resources rarely used will not be powered on if the domain it belongs to is not booted.