+See
+.Xr tunefs 8
+for more details on how to set this option.
+.It Fl a Ar maxcontig
+This specifies the maximum number of contiguous blocks that will
+be laid out before forcing a rotational delay (see
+.Fl d
+below).
+The default value is one.
+See
+.Xr tunefs 8
+for more details on how to set this option.
+.It Fl d Ar rotdelay
+This specifies the expected time (in milliseconds)
+to service a transfer completion
+interrupt and initiate a new transfer on the same disk.
+The default is 4 milliseconds.
+See
+.Xr tunefs 8
+for more details on how to set this option.
+.It Fl e Ar maxbpg
+This indicates the maximum number of blocks any single file can
+allocate out of a cylinder group before it is forced to begin
+allocating blocks from another cylinder group.
+The default is about one quarter of the total blocks in a cylinder group.
+See
+.Xr tunefs 8
+for more details on how to set this option.
+.It Fl i Ar number of bytes per inode