SUSE Labs Conference 2019 - Filesystems Native Support of Zoned Block Devices
Channel: SUSE Labs
Date: 2019-09-18

None

Zoned block device (ZBD) support has been introduced in Linux with kernel
version 4.10. ZBDs have different write constraints than regular block devices.
A ZBD is divided into several zones and each zone must be written sequentially.
The main type of ZBD currently available is SMR HDDs. The NVMe Zoned NameSpace
proposal is also being drafted to add a zone abstraction to the NVMe specifications.

Natively supporting ZBDs in a filesystem is not a trivial change. Some
filesystems must rely on special block layer drivers to ensure sequential writes
(e.g. ext4 and the dm-zoned device mappers). Filesystems using a copy-on-write
design are better candidates for native ZBD support. Examples are F2FS and btrfs.

This talk discusses the principles of ZBD native support in filesystems, with an
emphasis on the ongoing work in btrfs. Performance evaluation results and
comparison between filesystems with native ZBD support and regular ones using
the dm-zoned device mapper are also presented.

Damien Lemoal Naohiro Aota

https://labsconf.suse.cz/labs2019/talk/9J9HXB