> > It's odd. The usbmon log shows things working pretty well most of the > time, with transfer speeds around 200 Mb/s, but every now and then a > single 120-KB transfer takes more than half a second! > > I have no idea why. We can rule out hardware problems because it > doesn't happen under Fedora. Maybe interrupt delivery gets delayed > somehow under Ubuntu, or maybe something is different in the xhci-hcd > driver. Can you compare the driver source files? > > To do more serious testing will require you to build your own kernel, > or at least, your own version of the driver. > > Alan Stern > I'm getting a bit out of my depth now, but I'm pretty sure the xhci_hcd module is compiled into the Ubuntu kernels. If I were to dig around in Ubuntu's kernel sources looking for xhci_hcd.* files to diff against Fedora's, would that be a useful thing for me to do? It's been a few years but I have compiled my own kernels in the past, but I can definitely have a go at that if you think it would be beneficial. Thanks for your help so far Alan, it's very much appreciated. I know wizards of your level are busy people. -mat -- 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
