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@xxxxxxxxx
