HSMR – Hybrid Shingled Magnetic Media Recording disk drives. Hybrid SMR drives have both a conventional non-shingled magnetic recording (Conventional PMR or CMR) region and an SMR region. HSMR drives were specified by Meta’s (then Facebook) Open Compute Project (OCP) back in the 2012 era with OCP18. Western Digital and Seagate participated in the HSMR project. The idea is to spread the storage of hot data across across a set of disk drives by having hot data CMR regions on each drive rather than having the hot data occupy the totality of a disk’s surface, so as to increase the data access rate. The rest of an HSMR drive would be filled with cold data in an SMR region. This is an example of zoned namespace media.

OCP18 HSMR document diagram.

Download this OCP18 document to find out more.