Power management configs for Arch Linux (without laptop-mode-tools, powertop, etc)

linux-power-management

## Preamble

There are lots of tools out there that set power management, some more transparent (powertop), some less so (laptop-mode). Often it is hard to know what exactly the tool is doing to improvement power management. Here I would like to document some of the things I do to improve power efficiency and sometimes performance as well.

/etc/sysctl.d/99-sysctl.conf
> # To fix Dropbox not being able to handle too many files
> fs.inotify.max_user_watches = 524288
> 
> # VM writeback timeout (suggestion from powertop: In hundredths of a second, this is how often pdflush wakes up to write data to disk.)
> vm.dirty_writeback_centisecs = 1500
> 
> # Turn off NMI watchdog (suggestion from powertop: http://www.mjmwired.net/kernel/Documentation/nmi_watchdog.txt)
> kernel.nmi_watchdog = 0

# USB power management (https://www.kernel.org/doc/Documentation/usb/power-management.txt)
/etc/modprobe.d/usbcore.conf
> options usbcore autosuspend=-1 #prevent USB auto-suspend for new USB devices (http://unix.stackexchange.com/a/94024)

/etc/udev/rules.d/90-usbhid.rules (http://www.reactivated.net/writing_udev_rules.html)
> SUBSYSTEM=="usb", DRIVER=="hid-generic", ATTR{power/control}="on" #Keep USB HID devices on to prevent input lag