I have an XPS 13 Developer Edition Dell Laptop running Debian GNU/Linux Jessie (testing).
When the laptop starts up on battery power, the keyboard is so unresponsive that it is a real struggle to type in my password (key presses are delayed, ignored or stick and repeat many times).
It's OK if it's running off the mains, even if I boot with the battery and then plug it in.
I've not customised the default service configs (except trivial changes unrelated to this) and I keep my full list of
debfoster keepers on github if you'd like to see the services I have running.
How can I set the default laptop battery mode to be something usable?
systemd-analyze blame shows
1.084s kbd.service 394ms exim4.service 303ms NetworkManager.service 190ms ModemManager.service 179ms loadcpufreq.service 163ms laptop-mode.service 147ms accounts-daemon.service 129ms console-setup.service 117ms networking.service 100ms lightdm.service 98ms bluetooth.service 97ms systemd-logind.service 93ms keyboard-setup.service 89ms avahi-daemon.service 85ms systemd-fsck-root.service 73ms gpm.service
The time after the unit is active or started is printed after the "@" character. The time the unit takes to start is printed after the "+" character. graphical.target @2.434s ??multi-user.target @2.434s ??exim4.service @2.074s +358ms ??basic.target @2.070s ??timers.target @2.069s ??systemd-tmpfiles-clean.timer @2.069s ??sysinit.target @2.069s ??console-setup.service @1.936s +132ms ??kbd.service @531ms +1.403s ??remote-fs.target @531ms ??local-fs.target @530ms ??tmp.mount @524ms +5ms ??systemd-fsck@dev-disk-by\x2duuid-a2cf7f78\x2d691b\x2d4c01\x2da80c\x2d1bc6228230a5.service @466ms +57ms ??dev-disk-by\x2duuid-a2cf7f78\x2d691b\x2d4c01\x2da80c\x2d1bc6228230a5.device @465ms
but this seems consistent with and without the mains power supply.
Some more info:
- I don't experience the keyboard lag if I drop to a TTY.
- I have performed a
cpufreg-aperfboth with and without mains and the results are similar when the machine is idle or I'm just typing in the terminal.
- some people have claimed that disabling USB autosuspend helps, but I have the same problem even after disabling it entirely and rebooting.
- once I plug in the mains and then unplug it, the problem goes away.
- forcing the
performancecpu scaler (even on battery) doesn't help
- external USB keyboards are unaffected
Some hardware info:
lsusb Bus 001 Device 002: ID 8087:8000 Intel Corp. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 002 Device 004: ID 8087:07dc Intel Corp. Bus 002 Device 003: ID 0bda:5604 Realtek Semiconductor Corp. Bus 002 Device 002: ID 06cb:0af8 Synaptics, Inc. Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub xinput ? Virtual core pointer id=2 [master pointer (3)] ? ? Virtual core XTEST pointer id=4 [slave pointer (2)] ? ? SYNAPTICS Synaptics Large Touch Screen id=9 [slave pointer (2)] ? ? SynPS/2 Synaptics TouchPad id=12 [slave pointer (2)] ? Virtual core keyboard id=3 [master keyboard (2)] ? Virtual core XTEST keyboard id=5 [slave keyboard (3)] ? Power Button id=6 [slave keyboard (3)] ? Video Bus id=7 [slave keyboard (3)] ? Power Button id=8 [slave keyboard (3)] ? Integrated Webcam id=10 [slave keyboard (3)] ? AT Translated Set 2 keyboard id=11 [slave keyboard (3)] ? Dell WMI hotkeys id=13 [slave keyboard (3)]