On Mon, Nov 13, 2017 at 10:16 AM, Chris Murphy <lists@xxxxxxxxxxxxxxxxx> wrote: > On Mon, Nov 13, 2017 at 8:40 AM, Hans de Goede <hdegoede@xxxxxxxxxx> wrote: >> Hi all, >> >> As mentioned before I'm working on trying to improve the OOTB >> power-consumption of Fedora Workstation on laptops >> (I need to create an F28 feature page for this). >> >> On many laptops the btusb device is the only USB device not >> having USB autosuspend enabled, this causes not only the btusb >> device but also the USB controller to stay awake, together using >> aprox. 0.4W of power. Modern ultrabooks idle around 6W >> (at 50% screen brightness), 3.5W for Apollo Lake devices. >> 0.4W is a significant chunk of this (7 / 11%). >> >> So I would like to enable btusb autosuspend by default, to >> make this possible I've submitted the following kernel >> patch upstream which has just been merged (queued for 4.16): >> https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=86be3c232877b59f08561b256ff7e73ad39b0785 >> >> If it is ok with the Fedora kernel team I would like to add >> this as a patch to the Fedora kernels for now and set >> the new BT_HCIBTUSB_AUTOSUSPEND option to y. This is not >> without a risk of regressions, so this is something for >> rawhide/F28 only. > > > This is really useful work. I'm already seeing ~20% battery > improvement with Fedora 27 + 4.14.0-0.rc8.git3.1.fc28.x86_64 on an HP > Spectre, and so far no regressions. I get better battery life with > this combination than running Windows 10 with all the HP specific > drivers for this model. > > Some tips on how regressions might manifest and what information to > include in a good bug report would be useful. e.g. on an Intel NUC > when I run powertop --auto-tune, and walk away (it's a server so it > might be days) and come back the keyboard won't work. I've never done > any troubleshooting other than just disable the powertop systemd unit, > I'm vaguely suspicious of usb autosuspend and it not waking up when > keys are pressed. > Auto suspend can be a real problem when it is keyboards and mice. I know there was a huge uproar with logitech unified receiver users when powertop would change the receiver to autosuspend and the keyboard/mouse became unresponsive for a couple of key presses. To be honest, I think this particular change may do much more harm than good. Justin _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx
