[TriLUG] external USB drive is slow
porter at trilug.org
Thu Jan 12 16:26:32 EST 2006
This week, I bought a "Penguin Gear" external USB drive enclosure
and I put a 250 GB hard drive in it. It really looks sharp. I
want to store my rsync backups on it (I use the "rsback" script
that was presented to TriLUG in May 2004).
Last night, I hooked it up to my PC, a 550 MHz P-III with 256 meg
of RAM. Since the PC's built-in USB ports are USB-1, I bought a
cheap USB-2 card.
I formatted the disk and then started copying files like this:
( cd old_dir ; tar -cvf - .) | ( cd new_dir ; tar -xf - )
It ran and ran and ran. It took 12 HOURS to copy 31 GB!!! All
the time, the system load was between 2.5 and 3.0, but "top"
showed 99.0% idle.
Today, I have been trying to figure out why it is so slow.
I was wondering if there might be some interaction between the
on-board USB-1 controller and the new USB-2 card. The "usbtree"
script (http://www.linux-usb.org/usbtree) shows this:
/: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=ehci_hcd/6p, 480M
|__ Port 5: Dev 2, If 0, Class=stor., Driver=usb-storage, 480M
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=usb-ohci/2p, 12M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=usb-ohci/2p, 12M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=usb-ohci/2p, 12M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=usb-uhci/2p, 12M
|__ Port 2: Dev 2, If 0, Class=vend., Driver=none, 12M
|__ Port 2: Dev 2, If 1, Class=print, Driver=usblp, 12M
|__ Port 2: Dev 2, If 2, Class=vend., Driver=usbdevfs, 12M
I have very few leads to go on. Ideas?
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