SMR is a gamechanger drive technology, embraced by all major manufacturers. SMR changes fundamental assumptions of filesystem management. This long-help abandonment of Random-Writes now makes drives behave as sequential-access tape.

Seagate is leading the way in providing a standards compliant IO stack for use with the new drives. Using the new ZAC/ZBC commands to make and maintain a filesystem is essential for performant operation. Seagate is sharing lessons learned from modifiying EXT4 for use with SMR. This effort is called the SMR Friendly File System (SMRFFS).

Learning objectives: 1) Forward-write only considerations for the block allocation scheme

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2) Zones/BlockGroup/AllocationGroup alignment and use

, 3) Superblock, and other required write-in-place management schemes.

Slides are available in the show notes at www.snia.org/podcasts.