Background: NVMe specification has hardened over the decade and now NVMe devices are well integrated into our customers’ systems. As we look forward, moving HDDs to the NVMe command set eliminates the SAS IOC and driver stack, consolidating on a single access method for rotational and static storage technologies. PCIe-NVMe offers near-SATA interface costs, features and performance suitable for high-cap HDDs, and optimal interoperability for storage automation, tiering, and management. We will share some early conceptual results and proposed salient design goals and challenges surrounding an NVMe HDD. Discussion Proposal: We’d like to share our views and solicit input on: -What Linux storage stack assumptions do we need to be aware of as we develop these devices with drastically different performance characteristics than traditional NAND? For example, what schedular or device driver level changes will be needed to integrate NVMe HDDs? -Are there NVMe feature trade-offs that make sense for HDDs that won’t break the HDD-SSD interoperability goals? -How would upcoming multi-actuator HDDs impact NVMe? Regards, Tim Walker
