Dan Ritter wrote:
> USB2 disks are good for about 25MB/s.
>
Where do you have those numbers?
USB 2.0 standard can theoretically transfer data at a very high 480 megabits
per second (mbps), or 60 megabytes per second (MBps) [for example in
wikipedia).
but as you say it is slowing down at some point. It is not working at max
anyway - some people say it will not increase above 20MB/s anyway.
I suggest add to dd status=progress
The LEVEL of information to print to stderr; 'none' suppresses
everything but error messages, 'noxfer' suppresses the final transfer sta-
tistics, 'progress' shows periodic transfer statistics
And honestly I do not think 4TB disks were meant to be used via USB2 - think
of using eSATA.