NVMe emulator

Among the devices that OpenVMM emulates, an NVMe controller is one. The OpenVMM NVMe emulator comes in two flavors:

• An NVMe emulator that can be used to serve IO workloads (but pragmatically is only used by OpenVMM for test scenarios today)
• An NVMe emulator used to test OpenHCL (nvme_test), which allows test authors to inject faults and inspect the state of NVMe devices used by the guest.

This guide provides a brief overview of the architecture shared by the NVMe emulators. For how NVMe fits into the broader storage pipeline — including how namespaces map to DiskIo backends, online disk resize via AEN, and the layered disk model — see the storage pipeline page.