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Date:   Sat, 5 Mar 2022 15:09:55 +0900
To:     linux-raid@vger.kernel.org
From:   "Kengo.M" <kengo@kyoto-arc.or.jp>
Subject: Number of parity disks
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Hi Folks

I use mdadm conveniently.

Let me ask a very very basic question.

One parity disk can be used in RAID 5 and 2 parity disks can be used in RAID 6.
ZFS RAIDZ-3 (raidz3) can use 3 parity disks.

Is it difficult to increase the number of parity disks to 4, 5 or more.
If so, is the reason for this because of the time it takes to 
generate the parity bits?

Kengo Miyahara