Paper Title: ZNS in the Cloud with Ceph Crimson

Paper Abstract: (this was moved from the ZNS Category, per Matias Bjorling of WD) Zoned storage is a class of storage devices that have an address space that is divided into zones that have write constraints that are different from regular storage devices. Zones in zoned storage devices must be written sequentially. This is called the sequential write constraint. There are two technologies behind Zoned Storage, Shingled Magnetic Recording (SMR) in ATA/SCSI HDDs and Zoned Namespaces (ZNS) in NVMe SSDs. This talk will discuss the current status on ZNS support in CrimsonOSD/Seastore and WD's ongoing Ceph work. Seastore is a Ceph datastore based on the SeaStar framework. Seastore writes data sequentially to large segments on SSDs and keeping the segment size aligned to the erase block size or multiples of erase block size. This scheme of things suits the ZNS model very well where zones are mapped to erase blocks. The basic work needed to run CrimsonOSD and Seastore on ZNS drives is now upstreamed and we can run Crimson OSD on a ZNS device. This talk will also discuss initial benchmark numbers and opportunities of deploying ZNS in cloud using Ceph with Rook and Kubernetes as an example.

Paper Author: Aravind Ramesh, Principal Engineer, Western Digital

Author Bio: Aravind is currently working as a Technologist in Western Digital, Aravind is working on enabling Zoned Namespaces ecosystem including kernel, filesystems, databases and object stores.