Software RAID 5 and crashes

[Xuân Baldauf]

Hello,

I have been extensively searching for documentation and mailing lists, 
but was yet unable to answer this question:

Does Linux software RAID 5 (or RAID 4) do ordered writes? (data stripes 
first, then parity stripes)

Because if the writes are not ordered, parity stripes could be written 
before data stripes. If the system crashes at this time, reconstruction 
will  try to reconstruct the parity stripes by using the wrong (old) 
data stripes.

If the writes are ordered, crashes after the write of the data stripe 
but before the write to the parity stripe do not harm.

Thanks,

Xuân Baldauf.

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