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I'm zeroing a drive with
dd if=/dev/zero of=/dev/sdd
on a USB 3.0 port and it appears that the disk is writing half of the time and reading half of the time.
17564 be/4 root 10.59 M/s 10.59 M/s 0.00 % 96.60 % dd if=/dev/zero of=/dev/sdd
The performance is slower than what I expect, only being ~10M/s write and it looks like the rest of the bandwidth is being taken up by reads. The disk is not mounted nor being used by any other program.
Is this expected with