FPGA Virtualization in Cloud-Based Infrastructures Over Virtio

In this paper, we introduce a novel framework for virtualizing FPGA resources in the cloud. The proposed framework targets hardware/software architectures that leverage the Virtio paradigm for efficient communication between virtual machines (VMs) and the FPGAs. Furthermore, we present an FPGA overlay that uses reconfigurable hardware tiles and a flexible network-on-chip (NoC) architecture for transparent and optimized allocation of FPGA resources to VMs. The proposed overlay makes it possible to merge several FPGA regions allocated to a VM into a larger area, thus allowing resizing of FPGA's resources on demand. Hardware sandboxes are then provided as a means to enforce domain separation between hardware tasks belonging to different VMs. The framework introduced prevents the overhead of context switches between the virtual machine and host address spaces by using the in-kernel network stack for transferring packets to FPGAs. Experimental results show a 2x to 35x performance increase compared to current state of the art virtualization approaches.