NVMePass: A Lightweight, High-performance and Scalable NVMe Virtualization Architecture with I/O Queues Passthrough

Most data-intensive applications currently run on NVMe storage, and virtualization is essential in cloud computing. Existing NVMe virtualization technologies include software-based and hardware-assisted. Virtio suffers from severe performance degradation, and polling-based solutions consume too many valuable CPU resources. Hardware-assisted solutions provide high performance and no CPU usage but have the challenges of developing dedicated hardware.In this paper, we propose NVMePass, a novel software-hardware co-design NVMe passthrough virtualization architecture designed to achieve high performance and no CPU overhead while maintaining high scalability. The key ideas of NVMePass are NVMe I/O queues passthrough for VMs and a mechanism to ensure security. The NVMePass supports DMA and interrupts remapping for VMs without hypervisor involvement, eliminating virtualization overhead and providing near-native performance. Isolation is achieved by I/O queues and logical block address resources exclusively allocated to VMs. We propose NVMe Resource Domain (NRD) and implement it in the NVMe controller to intercept illegal I/O requests. Thus, isolation and security are fully achieved. Results from our experiments show that NVMePass can provide comparable performance to VFIO, with an IOPS of $\mathbf{1 0 0. 1 \% - 1 0 0. 5 \%}$ of VFIO. Furthermore, compared to SPDK-Vhost, NVMePass achieves $\mathbf{4 0. 0 \%}$ lower latency when running 150 VMs, and NVMePass has an improvement of $\mathbf{6 8. 0 \%}$ OPS performance in a real-world application when running 100 VMs.