There has been an increase in the complexity of embedded systems, requiring greater levels of functionality, flexibility, and efficiency. In order to meet these demands, virtualization techniques have emerged as a powerful solution. Virtualization increases performance, flexibility, and reliability of embedded systems by allowing the simultaneous execution of multiple operating systems or applications on a single hardware platform. Virtualization techniques used in embedded systems are discussed in this article, along with their benefits.
Full Virtualization: The ability to run more than one guest operating system on the same physical hardware platform is known as full virtualization. In order to achieve this, it creates a virtual machine (VM) layer that emulates the hardware resources required by each guest OS. In addition to providing an independent execution environment, the VM layer acts as an intermediary, isolating each guest OS. On modern embedded systems, full virtualization ensures compatibility with legacy software and allows legacy applications to run seamlessly.
Para-virtualization: In contrast to full virtualization, para-virtualization requires guest operating systems to be modified. In order to communicate with the virtualization infrastructure, guest OSes make use of specialized hypercalls. By bypassing emulation and allowing direct access to hardware resources, para-virtualization reduces the overhead of virtualization. Real-time embedded systems benefit from this technique since it improves performance and reduces latency.
Containerization: The use of containers, popularized by technologies such as Docker, allows embedded systems to operate as lightweight virtual machines. Multiple isolated containers can be executed on a shared kernel, each containing an application and its dependencies. Traditional virtual machines take longer to start up and consume more resources than containers. Embedded applications can also be deployed easily, scalable, and reproducible with them. It is especially useful for IoT devices and edge computing scenarios that require limited resources and fast deployment.
Hardware-Assisted Virtualization: By leveraging specialized processor features, hardware-assisted virtualization further optimizes virtualization in embedded systems. Virtualization technologies such as Intel VT-x and AMD-V enable direct support for virtualization, reducing overhead and improving performance. In fields such as automotive, aerospace, and industrial automation, hardware-assisted virtualization enhances the efficiency and scalability of virtualized embedded systems.
Real-Time Virtualization: A real-time virtualization approach addresses the requirements for predictive and deterministic behavior of embedded systems. Real-time virtualization ensures timely execution of critical tasks while running multiple guest operating systems or applications by integrating real-time scheduling algorithms and dedicated virtualization techniques. Safety-critical applications require this technique, where failure to meet strict timing constraints can have serious consequences.
Embedded systems have been transformed by virtualization techniques, allowing for improved performance, flexibility, and resource utilization. Embedded systems can take advantage of virtualization techniques whether they are fully virtualized, paravirtualized, containerized, hardware-assisted virtualized, or real-time virtualized. For modern applications and industries, virtualization techniques will become increasingly indispensable as embedded systems become more complex.
