for the watts

dependencies

• bash
• udev
• hdparm
• iw

configuration

The config file is located at /etc/conf.d/ftw.

universal options

PROFILE_FILE

• File to which the current profile name will be written after the profile is called.

MODULES

• Array of modules to be removed when offline and inserted when online.

PARTITIONS

• Device partitions affected by REMOUNT_OPTIONS.

DEVICES

• Devices affected by BLOCKDEV_READAHEAD, HD_POWER_MANAGEMENT, and HD_SPINDOWN_TIMEOUT.

state-dependent options

CPUFREQ_GOVERNOR

• CPU power scheme governor.

NMI_WATCHDOG

• Execute periodic NMI interrupts to monitor CPU lock ups?

BUS_CONTROL

• Control everything in /sys/bus/*/devices/*.
• on means device should be resumed and autosuspend is not allowed.
• auto means device is allowed to autosuspend and autoresume.

USB_AUTOSUSPEND_TIMEOUT

• How long to wait before suspending USB devices.

PCIE_ASPM_POLICY

• PCI Express Active State Power Management.
• Will probably require pcie_aspm=force kernel boot parameter.

LAPTOP_MODE

• Attempt to maximize the amount of time disks spend in a low power state by submitting all future pending disk IO when performing an IO operation?

DIRTY_RATIO

• Maximum percentage of memory dirty pages can occupy before processes are forced to write dirty buffers themselves.

DIRTY_BACKGROUND_RATIO

• Maximum percentage of memory dirty pages can occupy before pdflush begins to write them.

DIRTY_EXPIRE_CENTISECS

• How long data can be in the page cache before it expires, signifying it must be written at the next opportunity.

DIRTY_WRITEBACK_CENTISECS

• How often pdflush wakes up to write data to disk.

SCSI_HOST_POLICY

• Policy for SCSI host adapters.

REMOUNT_OPTIONS

• Comma-separated list (option1,option2,etc) of mount options to be applied when remounting devices.

BLOCKDEV_READAHEAD

• Block device readahead in kilobytes.

HD_POWER_MANAGEMENT

• Hard drive Advanced Power Management.
• See hdparm(8) (-B flag section) for more information.

HD_SPINDOWN_TIMEOUT

• How long to wait after disk activity stops before turning off hard drive's spindle motor.
• See hdparm(8) (-S flag section) for more information.

SND_INTEL_POWER_SAVE

• Enable Intel HDA audio chipset power saving?

SND_AC97_POWER_SAVE

• Enable AC97 audio chipset power saving?

WIRELESS_POWER_SAVE

• Enable wireless adapter power saving?

BACKLIGHT_BRIGHTNESS

• Dim backlight to save power?
• For max value (min is 0), check /sys/class/backlight/acpi_video*/max_brightness.

custom profiles

Custom profiles added to the config file can be called with ftw profile.

custom commands

Custom commands added to profile definitions will be executed when the profile is called.

examples

Disable Wake-on-LAN on battery with ethtool:

bat() {
    ethtool -s eth0 wol d
}

adp() {
    ethtool -s eth0 wol g
}

Manage backlight brightness per profile using relight:

bat() {
    if [[ -f $PROFILE_FILE && $(< $PROFILE_FILE) == 'adp' ]]; then
        relight save adp
        relight restore bat
    fi
}

adp() {
    if [[ -f $PROFILE_FILE && $(< $PROFILE_FILE) == 'bat' ]]; then
        relight save bat
        relight restore adp
    fi
}