On Mon, Jul 23, 2012 at 08:06:22AM -0700, Greg KH wrote: > On Mon, Jul 23, 2012 at 09:23:53AM +0800, Lan Tianyu wrote: > > On 2012年07月21日 01:08, Sarah Sharp wrote: > > >On Thu, Jul 19, 2012 at 11:42:57AM +0200, Oliver Neukum wrote: > > >>On Thursday 19 July 2012 15:42:37 Lan Tianyu wrote: > > >>>On 2012年07月19日 14:37, Oliver Neukum wrote: > > Moreover, the block layer also will check the disk status periodically. > > AS alan pointed, echo 0 >/sys/block/sdX/events_poll_msec to stop check > > event. So before I tested, I kill udev and disable the block layer check > > event. Finally, I got stable power consumption. I will also test other > > usb3.0 devices. > > By disabling this, you are not creating a real-world situation. Those > disks need to be polled for a reason, right? Tianyu is trying to test the port power off mechanism with USB 3.0 devices, to make sure the patches work on USB 3.0. Since the majority of USB 3.0 devices are storage, he needs to disable the polling to run tests. Yes, killing udev is an extreme measure, and using Alan's suggestion to stop the block device polling file is better. Yes, this is just a test and not something we can do in a real Linux distro. Sarah Sharp -- 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
