hesela.devInterlaced magnetic recording
Interlaced magnetic recording alternates partially overlapping top and bottom tracks so that a bottom-track update can affect valid data on its two neighboring top tracks.
Top and bottom name overlapping track roles, not opposite platter surfaces. The studied layout permits a top-track update without the same neighbor-rewrite requirement. [1]
Preservation policy matters independently of the layout. IMRSim holds affected data in memory, whereas KVIMR describes an ordered backup-region and restore sequence. A count of neighboring tracks is therefore not a complete byte-write or durability contract. [3] [2]
The linked Hesela analysis separates disk reads from writes in six constructed examples. Its numbers are accounting results, not physical IMR observations or a reproduction of either system. [4]
Relations
- related
- Shingled magnetic recording (SMR), Heat-assisted magnetic recording (HAMR), Hard disk drive (HDD), Write amplification, Hot/cold data separation
Limitations
- The reviewed simulation and CMR-backed emulation do not establish the performance or power-loss behavior of a commercial IMR drive. [1, 2, 3]
Citations
- Wu et al. Data Management Design for Interlaced Magnetic Recording. HotStorage 2018, sections 1-3.
- Liang, Yang and Yang. KVIMR. USENIX ATC 2021, sections 3.3-3.4 and 4.1.
- Zeng et al. IMRSim. arXiv:2206.14368v1, sections 2.1 and 3.
- Hesela: Interlaced recording, preservation policy and byte accounting
Sources & caveats
- Research-design record based on versioned papers. No contemporary product-availability survey, simulator execution, hardware measurement or crash-safety validation is claimed.