Low Cost Storage with SMR: State of the Art and Future Work
CEME 1210 | Fri 07 Aug 5:30 p.m.–6:15 p.m.
Presented by
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Damien Le Moal manages the System Software Group within WD Research. Damien has over 30 years of experience in the area of system software, operating systems and storage software solutions. Damien is involved in research activities including block device management and file systems. He is a regular contributor to the Linux kernel (file systems, block layer, SCSI, ATA and NVMe subsystems), is the maintainer of the kernel ATA subsystem and of the zonefs file system, and is the author and maintainer of several open-source projects.
Damien Le Moal manages the System Software Group within WD Research. Damien has over 30 years of experience in the area of system software, operating systems and storage software solutions. Damien is involved in research activities including block device management and file systems. He is a regular contributor to the Linux kernel (file systems, block layer, SCSI, ATA and NVMe subsystems), is the maintainer of the kernel ATA subsystem and of the zonefs file system, and is the author and maintainer of several open-source projects.
Abstract
Shingled Magnetic Recording (SMR) brings significant storage cost reduction for various workloads (e.g. Cloud, AI inference, backup, archive) by enabling more storage capacity and reliability. Adoption of SMR in production systems has accelerated in recent years, and over 65% of the Exabytes shipped in 2026 are forecast to be SMR. The Linux kernel supports SMR HDDs since version 4.10, released in 2017. After nearly ten years upstream, this support is now mature, with significant improvements compared to its early days. Several kernel file systems now natively supporting SMR, or zoned block devices in general.
This presentation starts with discussing the general characteristics of the kernel support for zoned block devices and the most recent kernel changes in this area to improve ease of use for end-users as well as for developers. Best practices for application development are discussed and illustrated with some performance results for workloads using a block device and using a file system, showing the viability of SMR compared to regular HDDs. Several features under consideration and development (prototyping phase) are also presented, including on-going work to support HDD data-preserving head depopulation and its integration within file systems.
Shingled Magnetic Recording (SMR) brings significant storage cost reduction for various workloads (e.g. Cloud, AI inference, backup, archive) by enabling more storage capacity and reliability. Adoption of SMR in production systems has accelerated in recent years, and over 65% of the Exabytes shipped in 2026 are forecast to be SMR. The Linux kernel supports SMR HDDs since version 4.10, released in 2017. After nearly ten years upstream, this support is now mature, with significant improvements compared to its early days. Several kernel file systems now natively supporting SMR, or zoned block devices in general.
This presentation starts with discussing the general characteristics of the kernel support for zoned block devices and the most recent kernel changes in this area to improve ease of use for end-users as well as for developers. Best practices for application development are discussed and illustrated with some performance results for workloads using a block device and using a file system, showing the viability of SMR compared to regular HDDs. Several features under consideration and development (prototyping phase) are also presented, including on-going work to support HDD data-preserving head depopulation and its integration within file systems.