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A comment on Don’t Be Afraid of RAID. Parent comment

Re:Don’t Be Afraid of RAID by singron on Sunday May 24, 2020 @05:38PM (#23295050)
What parameters are you using to make btrfs waste 6TB? With 2 copies (RAID1) and 2+4+6+8, that calculator shows it with 0 unusable space?
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Re:Don’t Be Afraid of RAID by matheusmoreira on Sunday May 24, 2020 @05:41PM (#23295076)
I used RAID 6. That's 1 copy and 2 parity stripes.
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Re:Don’t Be Afraid of RAID by singron on Sunday May 24, 2020 @05:52PM (#23295173)
Ah that explains it. Don't use parity with btrfs (i.e. RAID5/6). If you really want that, that's a good reason not to use btrfs.
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Re:Don’t Be Afraid of RAID by matheusmoreira on Sunday May 24, 2020 @06:27PM (#23295442)
Because of the write hole, right? I've been avoiding btrfs because of that issue. Multiple copies are too wasteful and the parity implementation isn't perfect. Hope it gets fixed soon.
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Re:Don’t Be Afraid of RAID by zrm on Sunday May 24, 2020 @11:08PM (#23297382)
That was recently fixed in mdadm. You can now specify a journal device (--write-journal) which closes the write hole. I don't see any reason btrfs couldn't do something equivalent.
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