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Psirus

Member

Registered: 2012-01-29

Posts: 45

External USB Harddrive very slow

I'm trying to connect an external hard drive, but it is painfully slow:

psirus|~» sudo hdparm -t /dev/sdb1
/dev/sdb1:
 Timing buffered disk reads:   4 MB in  4.49 seconds = 912.89 kB/sec

This is the "relevant" part from dmesg:

[ 2627.437362] usb 3-1: USB disconnect, device number 6
[ 2646.065014] usb 1-1: new high-speed USB device number 5 using ehci-pci
[ 2646.394778] usb 3-1: new full-speed USB device number 7 using ohci-pci
[ 2646.544156] usb 3-1: not running at top speed; connect to a high speed hub
[ 2646.559147] usb-storage 3-1:1.0: USB Mass Storage device detected
[ 2646.560295] scsi host4: usb-storage 3-1:1.0
[ 2647.568474] scsi 4:0:0:0: Direct-Access     WD       Elements 1023    2005 PQ: 0 ANSI: 4
[ 2647.580454] sd 4:0:0:0: [sdb] 976769024 512-byte logical blocks: (500 GB/465 GiB)
[ 2647.594492] sd 4:0:0:0: [sdb] Test WP failed, assume Write Enabled
[ 2647.608354] sd 4:0:0:0: [sdb] Asking for cache data failed
[ 2647.608376] sd 4:0:0:0: [sdb] Assuming drive cache: write through
[ 2647.697514]  sdb: sdb1
[ 2647.758500] sd 4:0:0:0: [sdb] Attached SCSI disk

What's the problem and what can I do about it? I've already tried switching cables, to no avail.

Last edited by Psirus (2015-03-08 21:14:12)

wtx

Member

Registered: 2014-06-09

Posts: 90

Re: External USB Harddrive very slow

Is your hard drive connected to any kind of usb-hub?  If yes - what kind of usb hub is it?
Seems like your hard drive is connected at USB full-speed - it means that it will work at 12Mbps, and that is way it is so slow.