Immutable Linux systems and how they work
summary
Compares three concrete approaches: A/B root partitions (two 20 GB roots, updates applied to B then merged), OSTree commits and refs as filesystem snapshots, and a custom OverlayFS-based system called Akshara that keeps a single root partition, installs packages into per-user overlays, updates by extracting squashfs from ISOs and swapping roots in an initramfs hook via a rename that the talk claims takes zero seconds, and reports no measurable OverlayFS slowdown while avoiding dependency hell.
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chapters (8)
- 0:00Introduction
- 1:00What is immutability
- 2:00Immutability implementations
- 3:45File attributes are mutability
- 4:40Overlay FS
- 6:14Update FS
- 7:55Conclusion
- 8:35Questions
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