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A comment on OpenZFS launch. Parent comment

Re:OpenZFS launch by babas on Wednesday September 18, 2013 @03:26AM (#6404002)
Just to make it clear. raid-5/6 mdadm arrays does the right thing when repairing/checking/scrubbing data. It writes the correct data if one of the drives has a corrupted block.

https://raid.wiki.kernel.org/index.php/RAID_Administration

  How often does this happen? According to what I have been reading, without ECC RAM and without ZFS, your machines get roughly one corrupt bit per day. In other words, that could be a few corrupt files per week.
This is complete nonsense without more data to back it up.
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Re:OpenZFS launch by GalacticDomin8r on Wednesday September 18, 2013 @06:12PM (#6408501)
> Just to make it clear. raid-5/6 mdadm arrays does the right thing when repairing/checking/scrubbing data.

This is inherent to RAID-5/6. Doesn't really have anything to do with mdadm other than mdadm implements RAID-5/6. And now you probably have a write hole.

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Re:OpenZFS launch by IgorPartola on Wednesday September 18, 2013 @07:32AM (#6404624)
Here is one of the sources: http://linas.org/linux/raid.html
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Re:OpenZFS launch by GalacticDomin8r on Friday September 20, 2013 @08:33AM (#6417269)
Just to make it clear: on raid 5/6 parity isn't checked on reads, so to get your "right thing when repairing/checking/scrubbing data" you'd have to do a full parity rebuild. This isn't anything like what ZFS does.
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