An I/O Virtualization Framework With I/O-Related Memory Contention Control for Real-Time Systems

Modern applications are often characterized by a tight interaction with I/O devices. At the same time, many application domains are also facing a shift toward an integrated approach where multiple applications with mixed levels of safety and security need to co-exist on top of a shared hardware platform, which is typically managed by a hypervisor. This gives rise to the need for a predictable mechanism allowing multiple virtual machines to share I/O devices, while at the same time controlling contention delays when they access global memory. To deal with these shortcomings, this article proposes an I/O virtualization framework providing support for controlling the I/O-related memory contention by leveraging the ARM QoS-400 regulators. Extensive experiments are performed to compare the proposed solution with the Xen hypervisor, showing improvements up to $8\times $ when controlling the I/O-related memory contention.