To clarify, the sequential read bandwidth of a RAIDZN with M total disks will be M times the read bandwidth of a single disk. The sequential write bandwidth wil

To clarify, the sequential read bandwidth of a RAIDZN with M total disks will be M times the read bandwidth of a single disk. The sequential write bandwidth will be (M-N) times the write bandwidth of a single disk. These are optimal values. https://calomel.org/zfs_raid_speed_capacity.html https://calomel.org/zfs_raid_speed_capacity.html It's a constraint on iops in particular, not bandwidth, because writing a record to disk involves writing something to every disk in the pool. So if you have a disk that's taking a long time to write, the other disks need to pause and let it catch up.