Hi, > HI Hendrik, > How are you measuring the speed? Are the tests all done at the > same time? What is the contents of /proc/bus/usb/devices with one of the > "slow" ones plugged in? One issue in the 2.6 kernel is that you could be > using the Low Performance USB SCSI driver (ub). That doesn't explain the > Firewire problem though...
thanks for your answer, this is the output of /proc/bus/usb/devices for pl-3507 with 250 GB Seagate: T: Bus=04 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 3 Spd=480 MxCh= 0 D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=067b ProdID=3507 Rev= 1.00 S: Manufacturer=Prolific Technology Inc. S: Product=Mass Storage Device C:* #Ifs= 1 Cfg#= 1 Atr=c0 MxPwr=100mA I: If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms E: Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms As you also said, that seems to be not the problem. Anyway, I should have said explicitly that the problem is only with writes. Reads are ok (with this setup around 17-18MB/s). I measured the speed with Midnight Commander, simply by copying a big file (700MB iso image) from the local hd to the external one. That is maybe not a perfect benchmark, but it's ok here. The tests are only done one at a time, so no bus sharing. I do not have any other USB devices (or FW devices) plugged in. The system is Debian Sarge in it's current state and a vanilla 2.6.11.7 kernel. If I remember right I had this problem also with the Debian 2.6.8 kernel. Maybe an interesting note: The external hd seems to make "abrupt noises", when I copy the data from local hd to the external hd. Copying from external to local makes the normal "flush noise". Hendrik > > regards, > > Stephen. > > On Sun, 24 Apr 2005, Hendrik Muhs wrote: > > > Hello, > > > > I have a strange problem with kernel 2.6.11.7 a Via KM400 based motherboard > > and external harddisks. > > > > I get only up to 500kb/s write speed over USB 2.0 and also FireWire 800. I > > have tried several combinations of harddisks, external cases (with different > > chipsets) > > > > The following table summarizes everything: > > > > connection chipset harddisk case harddisk speed > > USB-2.0 oxford 922 LaCie Big Disk ca. 500 kb/s > > USB-2.0 pl-3507 250 GB Seagate ca. 500 kb/s > > USB-2.0 oxford 922 250 GB Seagate ca. 500 kb/s > > USB-2.0 pl-3507 40GB IBM ca. 3-4 MB/s > > FW-800 oxford 922 LaCie Big Disk ca. 500 kb/s > > FW-800 oxford 922 250 GB Seagate ca. 500 kb/s > > FW-400 pl-3507 250 GB Seagate ca. 500 kb/s > > FW-400 pl-3507 40GB IBM ca. 18 MB/s > > > > All harddisks are ok and function normal on other systems. > > > > I have also tried a 2.4 kernel (a Knoppix Live CD with 2.4.29) which gives > > good results with the oxford 922 and the 250GB hd. Unfortunately I have to > > use an 2.6 kernel, because I need special drivers. > > > > The FW-800 card is based on a Texas instruments chipset and functions ok on > > the other system. > > > > It is strange that the problem seems to be not FW or USB related, maybe the > > SCSI subsystem? > > > > Also strange: I get better results with a smallsize (40GB) harddisk than with > > a big size (250GB) harddisk with the same case/chipset combination. The > > troughput is still too small (3-4 MB/s) but at least better. > > > > Has anyone an idea what is going wrong here? > > > > Or maybe can guide me, how to debug this problem. > > > > Hendrik > > > > > > ------------------------------------------------------- > > SF email is sponsored by - The IT Product Guide > > Read honest & candid reviews on hundreds of IT Products from real users. > > Discover which products truly live up to the hype. Start reading now. > > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > _______________________________________________ > > [email protected] > > To unsubscribe, use the last form field at: > > https://lists.sourceforge.net/lists/listinfo/linux-usb-users > > > > -- > /------------------------------------+-------------------------\ > |Stephen J. Gowdy | SLAC, MailStop 34, | > |http://www.slac.stanford.edu/~gowdy/ | 2575 Sand Hill Road, | > |http://calendar.yahoo.com/gowdy | Menlo Park CA 94025, USA | > |EMail: [EMAIL PROTECTED] | Tel: +1 650 926 3144 | > \------------------------------------+-------------------------/ > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > _______________________________________________ > [email protected] > To unsubscribe, use the last form field at: > https://lists.sourceforge.net/lists/listinfo/linux-usb-users ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
