`hdsize`::
Defines the total HD size to be used. This way you can save free
-space on the HD for further partitioning (e.g. for creating a swap-partition).
+space on the HD(s) for further partitioning (e.g. for creating a swap-partition).
+`hdsize` is only honored for bootable disks, i.e., only the first disk or
+mirror for RAID0, RAID1 or RAID10, and all disks in RAID-Z[123].
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