On Thu, 8 Feb 2007, Edwin Olson wrote: > > So I see. Do you happen to have the URB_NO_FSBR flag turned on in your > > URBs? > Not in my code, at least... What does it do?
It does pretty much what you said you saw -- it hints to the controller driver that this URB doesn't need more than one packet per frame. > > Have you tried using a USB bus analyzer to find out what's really > > happening? > I wish I had one! I have one. If you actually are at MIT you could come visit me. My office is just down the road, within walking distance. > More testing seems to indicate that multiple outstanding URBs does make > a very small (10%?) difference in performance, and staring at usbmon, it > appears that sometimes I do in fact get multiple callbacks from the same > frame. But it's quite rare... Bus analysis is the way to go. Alan Stern ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier. Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
