On Mon, 6 Feb 2006, [EMAIL PROTECTED] wrote: > Hi everybody, > I recently bought 2 large USB disk for doing backups. New disks are > approx. 400 GB in large, usb 2.0. My backup program (Bacula 1.36.3) > sucessfully writes to one of that disks and everything goes well. I > bought usb disks for quick solution for doing backups as my streamer > eaten another tape :? , and I would be happy to replace it with usb > disks for convienience, reliability and - price. > > The problem occurs when I need to copy a bigger file from one disk to > another: no matter if it is normal SCSI disk in the computer or second > USB drive. While copying bacula archive (a single file, which is 8GB in > large now and will grow up to 50GB) afer some time (300-900MB) copying > process slows down until it stops, slowly restart and continue copying. > Because of that slow average speed of copying to and from usb 2.0 is > about 2-3 MB/s only. While this process goes I can see in logs: > > [kernel] usb 1-2: reset high speed USB device using ehci_hcd and address 5 > > This line repeats continously until I finish copying. After starting > copying again, I still can see the message, but now since the very > beginning. Unregistering the device and restarting the backup machine > solves a problem until next copy. > > I've checked md5 sums of copies and they are correct (uf!), I can also > restore backups. I assume the problem lies somewhere in kernel, because > it happens also on another computer.
Not necessarily. The problem could lie in the drive or in the USB cables. Be sure to check or replace them, and don't forget the cables inside the computer case (if you're using one of the front-side USB ports that isn't directly adjacent to the motherboard). > I have to say that I really need a solution, because I feel unsafe to > perform backups to a device which is not managed correctly by my kernel. > Maybe I miss something in the kernel configuration or I need another > solution? The filesystem I use is ext3. To get more information, you should turn on the USB Mass Storage verbose debugging option in the kernel configuration (CONFIG_USB_STORAGE_DEBUG) and rebuild the usb-storage driver. For testing, use only one of the USB drives; unplug the other one. The usb-storage debugging option will generate a _lot_ of debugging messages, so make sure your /etc/syslog.conf is set up not to store debug-level messages from the kernel. Then go ahead and start writing a large amount of data to the drive. When you see those resets start to occur, run dmesg and post a copy of the output. Alan Stern ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642 _______________________________________________ Linux-usb-users@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
