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Charlotte lotteheartplural/Cinny cinny_heart_plural thetadelta ursaminor treblesand

i wonder why btrfs doesn’t have an erasure coded mode other than raid5/raid6 which has Issues

it would likely be far easier to take a 1MB extent, encode it with reed-solomon to become 3 500kB extents and store them on a different device each than to do raid5/raid6

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full read-modify-write operations are too slow in practice, and not doing them results in the raid write hole problem so why are you even bothering with raid5/raid6?

erasure coding is a much simpler solution and you could optimize it by special casing the case where only 1 part is needed or where n-1 parts are needed

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like

you are a file system. your entire job is to store extents on the disk somewhere. you don’t need to emulate being an emulation of block level parity striping as well because that makes zero sense

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