Am Dienstag, 19. Oktober 2010, 11:42:09 schrieb Sander Eikelenboom: > I was wondering why a USB2 device connected to a USB3 host controller causes much more interrupts then the same device on a USB2 controller. > Probably because there isn't a seperate roothub handling the USB2 devices ? > > usb2 controller > idle (no application grabbing video): 30 interrupts/second > active (application grabbing video): 155 interrupts/second > > usb3 controller > idle (no application grabbing video): 20 inter/second > active (application grabbing video): 7830 inter/second The ehci driver goes to great lengths to minimize the number of interrupts. What you are seeing here is likely simply one interrupt per URB. Regards Oliver -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
