powersave

#!/bin/sh

case "$1" in
	true) # Enable power saving settings on battery
	  logger "power saving mode enabled"

      # dim the brightness
	  echo 1 > /sys/class/backlight/acpi_video0/brightness

	  # bus
	  for i in /sys/bus/pci/devices/*/power/control; do echo auto > $i; done

	  # usb autosuspend
	  for i in /sys/bus/usb/devices/*/power/autosuspend; do echo 1 > $i; done
	  for i in /sys/bus/usb/devices/*/power/control; do echo auto > $i; done

	  ## disable nmi_watchdog
	  echo 0 > /proc/sys/kernel/nmi_watchdog

	  ## aspm
	  ##echo powersave > /sys/module/pcie_aspm/parameters/policy

	  ## kernel write mode
	  echo 5 > /proc/sys/vm/laptop_mode
	  echo 90 > /proc/sys/vm/dirty_ratio
	  echo 1 > /proc/sys/vm/dirty_background_ratio
	  echo 60000 > /proc/sys/vm/dirty_expire_centisecs
	  echo 60000 > /proc/sys/vm/dirty_writeback_centisecs

	  ## SATA Active Link Power management
	  for i in /sys/class/scsi_host/host*/link_power_management_policy; do echo min_power > $i; done

	  ## sound card powersave
	  echo 1 > /sys/module/snd_hda_intel/parameters/power_save
	  echo Y > /sys/module/snd_hda_intel/parameters/power_save_controller

	  ;;

	false) # Return to default on AC power

	  logger "return to default AC power"

	  # brighten up the screen
	  echo 7 > /sys/class/backlight/acpi_video0/brightness

	  ## bus
	  for i in /sys/bus/pci/devices/*/power/control; do echo on > $i; done

	  ## usb autosuspend
	  for i in /sys/bus/usb/devices/*/power/autosuspend; do echo 2 > $i; done
	  for i in /sys/bus/usb/devices/*/power/control; do echo auto > $i; done

	  ## enable nmi_watchdog
	  echo 1 > /proc/sys/kernel/nmi_watchdog

	  ## cpu frequency scaling
      #for i in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do echo ondemand > $i; done

	  ## aspm
	  ##echo default > /sys/module/pcie_aspm/parameters/policy

	  ## kernel write mode
	  echo 0 > /proc/sys/vm/laptop_mode
	  echo 30 > /proc/sys/vm/dirty_ratio
	  echo 30 > /proc/sys/vm/dirty_background_ratio
	  echo 3000 > /proc/sys/vm/dirty_expire_centisecs
	  echo 600 > /proc/sys/vm/dirty_writeback_centisecs

	  ## SATA Active Link Power management
	  for i in /sys/class/scsi_host/host0/link_power_management_policy; do echo max_performance > $i; done

	  ## sound card powersave
	  echo 0 > /sys/module/snd_hda_intel/parameters/power_save
	  echo Y > /sys/module/snd_hda_intel/parameters/power_save_controller
	  ;;
esac
exit 0