On Wed, Jun 1, 2011 at 8:59 PM, DJ Delorie <dj@xxxxxxxxxx> wrote: > >> Or does it happen with reads too? > > With both the sata drive (sda) and flash drive (sdb) (both usb) > connected, and network (also usb) up and running, I did some raw read > tests: > > dd if=/dev/sda1 of=/dev/null bs=4096 count=102400 > dd if=/dev/sdb1 of=/dev/null bs=4096 count=102400 > > sda       Â9.4 ÂMB/sec > sda+ping    Â23.4 > > sdb       Â7.8 > sdb+ping    Â21.3 > > both      Â14.7 each (29.4 total) > both+ping    14.0 each (28.0 total) > > So, the problem seems to happen if you have one usb-storage active and > no other usb activity, but other activity (either another usb-storage > or ethernet pings) seems to work around the problem. You also confirmed that one usb-storage and, quoting you: > a serial port connected to a 9600 baud character generator, > and got good performance. Likewise with a usb mouse, as long as I > wiggled the mouse during the test. Were you referring to an onboard serial port ttyS or ttyO, or a ttyUSB? _______________________________________________ arm mailing list arm@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/arm
