Shutdown From Suspend


This feature extends the battery life of Chrome OS device during prolonged non-use by proactively shutting down the device after a configurable time.


Chrome OS devices usually support at least 14 days of standby. Users that return to the device tend to do so in the first 3 days. Thus instead of sitting in standby until the battery is completely discharged, this feature shuts down the device proactively after spending configured time in standby. This helps in reducing battery degradation due to deep discharge. This can also reduce the frequency of trickle charges during boot.

This flowchart depicts the state machine for shutdown-from-suspend. shutdown-from-suspend flowchart

powerd before every suspend will schedule an alarm (that can wake the system from standby) if one is not already running for shutdown_from_suspend_sec pref. On every resume, powerd identifies if the wake is triggered by the user. If so, powerd stops the alarm and resets the state machine. If not, powerd checks if the timer set above has expired. If the timer has expired, powerd will shut down the device if line power is not connected.

Enabling shutdown-from-suspend on a new device

  • Make sure Dark Resume is enabled on the device.
  • Configure shutdown_from_suspend_sec pref for the device.

Debugging shutdown-from-suspend

Configuring shutdown-from-suspend on a test image

  • Enable Dark Resume on the test image.
  • Perform the following steps to enable shutdown-from-suspend:
# echo x > /var/lib/power_manager/shutdown_from_suspend_sec
# restart powerd

Disabling shutdown-from-suspend on a test image

Perform the following steps to disable shutdown-from-suspend:

# echo 0 > /var/lib/power_manager/shutdown_from_suspend_sec
# restart powerd