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`$ sudo dd if=/dev/zero of=/dev/mapper/to_be_wiped status=progress`
`59001459200 bytes (59 GB, 55 GiB) copied, 904 s, 65.3 MB/s`
65 MB/s, nice, nice. At this rate it's only going to take.... 3 days to wipe this 16TB drive.
@pganssle setting a larger block size (bs=1M for example) might help.