On Mon, 2 May 2005, Hendrik Muhs wrote: > I now found out a little bit more in this issue: > > I tried down to Kernel 2.6.6 without luck, also 2.4.30 does not give me > better > results. At least I found out why a live linux (Knoppix) had better results: > Simply the mount option sync was the cause, without sync I get 3-4 MB/s which > is still to slow, but at least much faster than before. > > > > > It would help to know exactly what's happening. Are the writes really > > slow, or are the transfers constantly interrupted by errors and the need > > to reset the drive? > > Yes, constantly interrupted ist the right description. Interesting is, that > with sync, the interrupts are more often, without sync one "write period" is > longer, but the pause seems also be longer. I can watch this process with the > LED of the drive, it copies for 1-2s, then stops for 0.5s than writes again > (I am still copying one big file).
That's not what I meant. The interruptions I was talking about would last for around 30 seconds and they would show up as errors in the usb-storage log. > > For a better error report, turn on USB Mass Storage verbose debugging in > > the kernel configuration. > > I could not see any error messages with USB Mass Storage turned on. As I have > said, I have got this problem with FireWire, too. Also no other drive errors > are reported, everything seems ok. > > If you have any other ideas where I can put debugging stuff in, please tell > me. At this point it sounds like you're limited by the speed either of the USB-IDE adapter or the disk drive. If everything is working okay than adding debugging statements won't help much; they'll just tell you what you already know. You could try doing your comparisons with multiple adapters and multiple drives again (without -o sync !) to see how they look now. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by: NEC IT Guy Games. Get your fingers limbered up and give it your best shot. 4 great events, 4 opportunities to win big! Highest score wins.NEC IT Guy Games. Play to win an NEC 61 plasma display. Visit http://www.necitguy.com/?r=20 _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
