Reliable power management

[Kellieward]

We are using PowerMAN (v5.2) software for our network power management. The deployment has been pretty painless (mixed XP and Window 7) but the results are not always consistent. Some workstations hibernate as expected whilst others stubbornly ignore the policy we've deployed. Does anyone know why this happens please?

[Michael]

You can control Win 7 Power Management natively with 2008 R2 by GPO. Works as expected.

[Kellieward]

Sorry, I should have mentioned - we tried basic GPO before PowerMAN. We found the consistency was even worse. Some PCs would behave whilst others totally ignored the policy. We liked PowerMAN because it offers some nice reports and multiple policies per workstation / user. However, still not totally consistent.

[AngryTechnician]

Did you try normal Group Policy or Group Policy Preferences before?

 

GPP is definitely picky about when it works and when it doesn't, but the regular Group Policy settings (under Computer Configuration/Policies/Administrative Template/System/Power Management) have always been rock solid for us.

Edited May 13, 2013 by AngryTechnician

[nobleguy]

Try enabling the PowerMAN Policy Enforcement settings. These solved this problem for us. We tried GPO and GPP (and lots of other stuff too) but in the end PowerMAN did the trick for us. Apparently the inconsistency is because applications can interfere with the power management timers. I've heard several suppliers refer to this as "PC insomnia". The manual says that the enforcement feature applies an additional "grace" period before overriding this.

 

Also, did you try looking in the PowerMAN reports? These show the periods where the PCs were prevented from power managing. This was a real eye-opener for us. It's amazing how much time applications and Windows spend fighting over this. When the enforcement widget was turned on this improved lots.

[dssupport]

You can always ring the vendor's technical support if you need help.

 

"PC Insomnia" is a major issue. It happens when you use an idle (time-out) policy for power management. Whenever a user stops typing / moving the mouse an idle timer starts to count down. This timer can be reset by an application to basically say "Stop, I'm doing something important". Most applications do this sometimes - some do it a lot. The effect will be worse with longer time-out periods and in practice, time-outs over perhaps 2 hours will rarely work because the opportunity to be interrupted is so great.

 

This is a common flaw with any power management approach that uses the underlying Windows timer such as basic GP or GPP. The better products implement their own timers to overcome this "insomnia". I would suspect they all work the same basic way. This is a major difference between basic "free" power management and the third-party products. In smaller organisations there may be less pressure in this area but in larger IT estates it is big business making sure that power management is effective as possible AND proved to be as effective as possible. This is why basic GPP/GP etc just don't cut it in these environments.

[Kellieward]

Thank you for the tips. I've enable the PowerMAN enforcement (aka "anti-insomnia") feature and I can already see a difference in yesterdays power management reports. I've started on the pupil machines and will then roll this out to the separate office workstations later.

 

BTW: Just to revisit the GP v PowerMAN debate - one important difference for us was that we could have a different policy when no user was logged on. We have configured student workstations to log off after 90 minutes and then sleep when nobody is logged on for a few minutes. We've taken a completely different approach for the admin staff workstations and just sleep after a few minutes (with the user still logged on). We encourage the users to log off and if they do the PC then shuts down fully. Hopefully this maximises the savings. I tried but can't see how you can do this with native GP alone.

[danjoslin]

We fought a long battle with PC "insomnia" before hitting on PowerMAN (PowerMAN PC Power Management Software for cost and energy savings by Data Synergy). We found that Microsoft products were especially bad at this and as the previous post said the longer the power management delay the worse the problem became. This shows up in the PowerMAN reports with a ! symbol to show the PC was being prevented from sleeping. You can have a play with this on their online demo: PowerMAN PC Power Management Software Demo (PowerMAN PC Power Management Software Demo)

 

One word of caution however: The anti-insomnia feature is certainly a big improvement on what is available in Windows but can be quite aggressive out of the box! We found it best to set the grace period to about 30 minutes. This gives any legitimate stuff time to complete whatever it is doing whilst preventing workstations from staying on forever. A possible more useful feature of PowerMAN is the so-called "No User" policy. We used this to turn off PCs that have nobody logged into them. Once turned off they stay off until a human being needs them again. This is the best form of power management. My suggested settings would be:

 

1. Staff: Sleep after 30 minutes when user logged in (and remember to require a password when they resume the PC!)

2. Students: Logout after 60 minutes when user logged in

3. All: Power off after 15 minutes when no user logged in

4. Enable policy enforcement with 30 minute grace period

5. Wake-up: Sunday mornings for 1 hour for WSUS updates

 

I wish this was possible with Windows alone but sadly it isn't. PowerMAN was a small cost but well worth it in the end.