On Tue, 15 Nov 2005, Neil Brown wrote: > Yes, I think changing the IDLE_TIMEOUT does help. > I think I now know enough about what is going on to decide that I have > a good-enough fix, and that it won't get any better (with either > berating HP to fix the printer, or using a USB2.0 interface). > > It seems that the printer only accepts data packets during a small > window ever 112msecs or so. It is vital that we hit that window to > get any sort of speed. > > With the default timeout, we only through packets steadily at the > printer for about 100ms. After that, we drop down to 1 per msec which > makes the hit rate much worse. > > So I've defined a new transfer_flag which disables the FSBR timeout, > and a printer quirk for my printer what sets this flag. > With this patch, I getting (barely) adequate performance - better than > 2.4 and much better than standard 2.6. > > Below is the patch - so if someone else has this problem they might > find the patch on the mailing list archives. > > I'll leave it up to you to decide if it should be submitted to > mainline.
Not just now. Can you get a usbmon log showing your change in action? It would be interesting to see the time intervals involved. It would also be worthwhile to see if you can get more or less the same effect without all those changes, just by increasing IDLE_TIMEOUT to 1000 ms or something like that. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today Register for a JBoss Training Course. Free Certification Exam for All Training Attendees Through End of 2005. For more info visit: http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
