USB Hard Drive Activity Slows down Host
Les Mikesell
lesmikesell at gmail.com
Mon Jun 19 20:34:40 UTC 2006
On Mon, 2006-06-19 at 12:22 -0700, Hugh Caley wrote:
> We regularly copy a few hundreds of gigabytes of data from a host
> running Fedora to a LaCie USB 2 hard drive in order to ship the data to
> an overseas company. We've noticed that initiating the copy causes the
> load on the machine to creep up and the machine to become very slow in
> response. Stopping the copy causes the load to slowly come down again.
>
> Machine is a quad processor (or dual dual-core) AMD Opeteron box running FC3
> 2.6.12-1.1381_FC3smp #1 SMP Fri Oct 21 04:22:48 EDT 2005 x86_64 x86_64
> x86_64 GNU/Linux
>
> dmesg info:
>
> Vendor: LaCie Model: BigDisk Rev:
> Type: Direct-Access ANSI SCSI revision: 00
> SCSI device sdc: 976794336 512-byte hdwr sectors (500119 MB)
> sdc: assuming drive cache: write through
> SCSI device sdc: 976794336 512-byte hdwr sectors (500119 MB)
> sdc: assuming drive cache: write through
> sdc: sdc1
> Attached scsi disk sdc at scsi6, channel 0, id 0, lun 0
> usb-storage: device scan complete
>
>
> There are no error messages. Any ideas?
I think there is quite a bit of CPU overhead in transferring
data through a USB controller. Firewire might be more
efficient if it happens to work in the kernel version you
are using (there have been problems over the last year or so).
--
Les Mikesell
lesmikesell at gmail.com
More information about the users
mailing list