Background: As the capacity of HDDs increases so is the need to increase performance to efficiently utilize this increase in capacity. The current school of thought is to use Multi-Actuators to increase spinning disk performance. Seagate has already announced it’s SAS Dual-Lun, Dual-Actuator device. [1] Discussion Proposal: What impacts multi-actuator HDDs has on the linux storage stack? A discussion on the pros & cons of accessing the actuators through a single combined LUN or multiple individual LUNs? In the single LUN scenario, how should the device communicate it’s LBA to actuator mapping? In the case of multi-lun, how should we manage commands that affect both actuators? For NVMe HDDs are namespaces the appropriate abstraction of the multiple actuators? We would like to share our work mapping LUNs/Actuators through LVM & MD-RAID to study the performance characteristics and hope to get some feedback from the community on this approach. [1] https://www.seagate.com/solutions/mach-2-multi-actuator-hard-drive/
