This feature is only applicable on Windows operating systems.

NightWatchman provides sleepless client detection to optimize a computer's ability to go into a sleep state, increasing power savings and energy efficiency in your organization. This feature specifically handles sleep events that occur due to Windows idle timers, for example a computer going to sleep after 30 minutes of inactivity. Sleepless client detection is not applicable for NightWatchman initiated power down events.

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Sleepless events occur frequently in normal computer usage, sometimes for very valid reasons and sometimes not. For example, you would not want a computer running a PowerPoint presentation to hibernate in the middle of an important slide. However, if you have left your computer for a long period of time, and it is not running any important tasks, then it should be saving power.

Sleepless client detection identifies the reasons why computers are being prevented from sleep, and enables the administrator to make informed decisions. It reports faulty input devices that are keeping the computer active by mimicking user keyboard or mouse activity. NightWatchman looks for at least one 30 second inactive period in the last 24 hours. If this has not occurred, it reports the input device as potentially unreliable.

In addition, sleepless detection identifies specific processes that are preventing an unattended computer from entering into a low-power state. These sleepless processes are defined as:

  • Busy process – a process that is causing CPU usage to exceed a set threshold
  • System required process – a process that has an OS execution state flag set to say that it is required. It therefore stops a computer from entering a suspend state due to a period of inactivity

NightWatchman can be set to ensure that busy processes on Windows Vista do not prevent a computer from sleeping, thereby reproducing the Windows 10, Windows 8.1 or Windows 7 behavior. To do this, set busyprocessdetection=off.

By default, NightWatchman is set to enable the default Windows Vista behavior where busy processes will prevent a computer from sleeping. This enables a baseline to be created that accurately measures system behavior prior to implementing NightWatchman savings.

When a default power policy is set from the NightWatchman Management Center Console, busyprocessdetection=off. NightWatchman also defaults to identifying system required processes by name and report these centrally. This is known as Advanced Sleepless Client Detection. The administrator can review this and add them to the sleepless exclusion list. NightWatchman ensures that a process named on the sleepless exclusion list cannot prevent the computer from sleeping.

Advanced sleepless client detection can be disabled at install time (use advancedsleeplessdetection=off on the command-line) or from the NightWatchman Management Center Console in a power policy definition. If you disable this feature, or if the version of the Windows kernel does not support querying process information, it will not be possible to identify the name of the process that is preventing the computer from going to sleep. However, faulty input devices will still be identified.


Sleepless detection information appears in two NightWatchman reports under the heading Sleepless Client Detection.

  • Busy and Sleepless Processes – reports processes running on the client computer that are the likely cause for it not entering into a low-power state.
  • Untrusted input device – reports potentially faulty input devices that are the likely cause for a client computer not entering into a low-power state.

Exclusion lists

Once you have reviewed the NightWatchman reports that identify potential reasons why a particular computer is being kept from entering into a sleep state, you can choose to add any processes named in the report to the sleepless exclusion list. You can add process names to the sleepless exclusion from:

  • NightWatchman Console – the most convenient is from a power policy in the NightWatchman Console. We recommend that the power policy with the excluded processes only gets applied to the computers reported against in the NightWatchman Busy and Sleepless Processes report.
  • 1E Agent command-line – there are a number of command-line switches that control the exclusion list such as: selistshow, selistadd, selistdel, selistfrom and selistclear.