Towards an Analysable, Scalable, Energy-Efficient I/O Virtualization for Mixed-Criticality Systems

In Mixed-Criticality Systems (MCSs), timely handling of I/O operations is a key for the system being successfully implemented and appropriately functioned. The I/O system for a MCS must simultaneously enable different features, including isolation/separation, timing-predictability, performance, scalability and energy-efficiency. Moreover, such I/O system also requires to manage I/O resource in an adaptive manner to facilitate efficient yet safe resource sharing among components of different criticality levels. Existing approaches cannot achieve all of these requirements simultaneously. This paper presents a mixed-criticality I/O management framework, termed MCSIOV. MCS-IOV is based on hardware-assisted virtualisation, which provides temporal and spatial isolation and prohibits fault propagation with limited extra overhead. MCS-IOV extends a real-time I/O virtualisation system, by supporting the concept of mixed criticalities and customised interfaces for schedulers, which offers good timing-predictability and scalability. Finally, we introduce an energy management framework for MCS-IOV, ensuring the power-efficiency of the design. The MCS-IOV is the first systematical solution that fulfils all the requirements as a mixed-criticality I/O system.