USB physical ports
patrickhess at gmx.net
Fri Sep 11 10:11:35 UTC 2015
Ernie Luzar wrote:
> How can I confirm 480Mbps transfer rate.
Run "dmesg -a" after plugging in the device. A USB 2.0 flash drive
should be reported with a 40 MB/s transfer rate:
da1: <Intenso Rainbow Line> Removable Direct Access SCSI-4 device
da1: 40.000MB/s transfers
You can verify this by reading from the drive, e.g. by using dd(1):
# dd if=/dev/da1 of=/dev/zero bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes transferred in 52.099073 secs (20609615 bytes/sec)
That's ~20 MB/s, definitely more than USB 1.x could have delivered.
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