NVMeVirt: A Versatile Software-defined Virtual NVMe Device

There have been drastic changes in the storage device landscape recently. At the center of the diverse storage landscape lies the NVMe interface, which allows high-performance and flexible communication models required by these next-generation device types. However, its hardware-oriented definition and specification are bottlenecking the development and evaluation cycle for new revolutionary storage devices.

In this paper, we present NVMeVirt, a novel approach to facilitate software-defined NVMe devices. A user can define any NVMe device type with custom features, and NVMeVirt allows it to bridge the gap between the host I/O stack and the virtual NVMe device in software. We demonstrate the advantages and features of NVMeVirt by realizing various storage types and configurations, such as conventional SSDs, low-latency high-bandwidth NVM SSDs, zoned namespace SSDs, and key-value SSDs with the support of PCI peer-to-peer DMA and NVMe-oF target offloading. We also make cases for storage research with NVMeVirt, such as studying the performance characteristics of database engines and extending the NVMe specification for the improved key-value SSD performance.