School of Earth, Energy & Environmental Sciences

Power management to be implemented on Earth Sciences computers



Last revision July 2, 2010; minor revision September 30, 2010

Inventory tag As part of the university's sustainability initiatives, power management features were centrally enabled on Stanford-owned CRC supported computers in Earth Sciences using the BigFix program on July 14, 2010. Personally-owned computers were not affected. As new computers are installed by CRC, these power management settings will also be applied to them. CRC supported computers have a red barcode sticker like this sample:

Two BigFix power management alternatives are used:

  • Stanford Yellow just puts the monitor to sleep (cuts power to the monitor so it goes blank) when the computer is inactive. This does not affect any running programs or network connections.

  • Stanford Green starts by putting the monitor to sleep when the computer is inactive, but after a longer period of inactivity, it puts the entire computer to sleep so it is using only the minimum amount of power needed to maintain memory but not run any programs. This saves more energy than just monitor sleep, but possibly has disruptive side effects (see below).

The computer is considered to be inactive when there is no keyboard or mouse activity. Once sleep mode is activated, the computer will return to normal operation, usually instantly, by simply pressing any key on the keyboard or moving the mouse.

Stanford Yellow is the base power management alternative that is applied to all CRC supported computers in the School of Earth Sciences.

The more aggressive Stanford Green alternative is applied to office computers in Mitchell Earth Sciences Building and Geology Corner to support the specific Building Level Sustainability Program for those buildings, as recently announced by Dean Matson.

If the power management alternative applied to your computer is not appropriate to your work style, you can download and use the Stanford Power Management Tool to select the other level or "opt out" entirely.

Questions and Answers about the BigFix power management program

Which computers are affected?

Power management is centrally implemented only on Stanford-owned Windows and Macintosh computers that are inventoried and supported under the School of Earth Science's contract with the Computer Resource Consulting group of ITS. These computers all have a red and white barcode sticker (see sample at top of page). The BigFix management agent has been installed on all these computers and is used to enable power management remotely.

The vast majority of computers in the Energy Resources Engineering department are not supported by CRC and are not affected by this program. Only computers with the CRC inventory sticker are affected.

Personally-owned computers, servers, and Linux systems are not affected.

If your computer is not part of this program, you are encouraged to set power management manually as appropriate to save energy.

Will my Stanford-owned laptop computer still go to sleep if I take it home or into the field?

Yes, if this laptop is supported by CRC and thus part of the BigFix power management program. The BigFix management agent changes the power management settings on your computer and they stay in effect no matter where you use the computer.

My laboratory computer needs to run all the time. Will this affect it?

Laboratory computers that are supported by CRC (have the inventory sticker) are included in the BigFix power management program. They are set to the Stanford Yellow setting. This setting only puts the monitor to sleep when the computer is inactive. Simply moving the mouse or pressing a key will bring the monitor image back if it has gone to sleep. This setting never puts the entire computer to sleep (except for laptops on battery power) so it will not interrupt any running programs or network connections.

This power management setting should be appropriate for almost all laboratory computers, many of which are used to control or monitor instruments. In the rare case that the monitor simply must stay on all the time, you can change your BigFix power management setting to None and thus "opt out" of the program.

When my computer is inactive, how soon does power management start up?

This table shows how long the computer must be inactive before monitor or computer sleep starts under the two different BigFix power management settings. "Inactive" means that no keyboard or mouse activity is detected during the time shown. When you use the mouse or keyboard, you "reset the timer".

Setting Monitor sleeps (goes blank) Entire computer sleeps
Stanford
Green 		After 10 minutes inactive
(5 minutes on battery power) 		After 30 minutes inactive
(20 minutes on battery power)
Stanford
Yellow 		After 15 minutes inactive
(10 minutes on battery power) 		Never when on building power
(after 30 minutes inactive on battery power)
Press a key or move the mouse to wake from the sleep setting.

What are the possibly disruptive effects of the Stanford Green setting?

Because this setting puts the entire computer to sleep when inactive more than 30 minutes, it can interfere with programs or tasks that are running but don't require any keyboard or mouse interaction. Power management generally doesn't realize that the computer is still "busy" unless the mouse or keyboard are being used.

Here are some examples of computer uses that can be disrupted by putting the computer to sleep in the Stanford Green power management setting. If these scenarios, or others like them, apply to your office computer in Mitchell or Geology Corner (the only computers scheduled for the Stanford Green setting), then you should change to the Stanford Yellow setting, which does not put the computer to sleep, only the monitor.

  • You start a long running program, such as a long Matlab calculation, and then leave the computer alone. Because there is no keyboard or mouse activity, the computer may appear to be inactive after 30 minutes and power management will put it to sleep. This will interrupt your program and prevent it from finishing.

  • You leave your office computer on at night so you can remotely connect into it from home, using, for example, ssh, Remote Desktop (Windows), or Connect to Server (Mac OS X). But 30 minutes after you leave the office, power management will put the computer to sleep because there has been no mouse or keyboard activity. Depending upon the computer model, the remote connection may fail to wake up the computer.

  • You have setup a personal backup system that runs at a set time during the night. Again, power management will put your computer to sleep 30 minutes after you leave the office and the backup system is not likely to run. This scenario does not apply to the School's CrashPlan backup system for faculty and staff, which runs frequently during the day.

Will I have to enter a password to wake-up my monitor or computer?

Requirements to enter a password to wake up the computer are not affected by this BigFix power management system. That is, if you currently need to enter a password to wake up the computer from sleep mode, that will continue. If you don't need a password now, you won't need one after BigFix power management is enabled.

If my computer goes to sleep, will it still get backed up?

Your computer will continue to be backed up if you are using the School's CrashPlan backup system (for faculty and staff) or an Internet based system such as Iron Mountain or Mozy, or the Time Machine backup system built into Mac OS X.

These backup systems all run frequently and backup files as they are changed. They don't wait until the middle of the night or other set time to backup files. So by the time your computer goes to sleep after 30 minutes of inactivity, these programs should be done backing up any files you have recently changed.

On the other hand, if you have your own custom backup system that runs at a set time every day or night, it might not run if the computer has gone to sleep. In this case, either change your backup system to run during a time when the computer is normally active, or change your BigFix power management setting to Stanford Yellow, which does not put the computer to sleep, only the monitor.

Can I temporarily disable power management?

If you have administrative rights on your computer, you can manually change the power management settings, but your change will only last for the rest of the day.

BigFix power management works by changing your normal system settings - the same ones you can set manually. However, BigFix makes those changes using the administrative account, so you need to have administrative privileges to override them.

Furthermore, BigFix checks every day to see if the power management settings are still correct - if not, it fixes them. This check is done at 4 am every day, or as soon thereafter as the computer is turned on. So any change you make manually is "undone" the next day.

You can permanently change your BigFix power management settings.

How can I request a different setting or "opt out"?

You have the ability to control the BigFix power management setting applied to your computer.

There are circumstances where the standard BigFix power management settings are clearly not appropriate. For example, if you run programs on your office computer in Mitchell or Geology Corner that can take more than 30 minutes and you may leave the computer alone during that time, so it appears to be inactive, then the Stanford Green setting will not work for you because it will put your computer to sleep and interrupt the program before it finishes. In that case, you should switch to the Stanford Yellow setting. That setting just puts the monitor to sleep, which will not affect your running programs.

As another example, supported laboratory computers are set to the Stanford Yellow setting because they often need to run programs continuously to control or monitor instruments. In this case, the monitor will go to sleep after 15 minutes of inactivity, but the program will keep running. This is usually good enough, because you can wake up the monitor at any time to check program status. But if you need to have the monitor on all the time so you can glance at it at any time to check experiment status, then you should switch to the None level, which "opts out" of the program completely. Conversely, if the laboratory computer is only used for short term tasks, with no long-running programs, it could save more energy by switching to the Stanford Green setting.

To change your BigFix power management setting, simply download and run the Stanford Power Management Tool:
      Get Power Management Tool for PCs running Windows XP or later
      Get Power Management Tool for Mac OS X 10.4 or later

Clicking on one of the links above should download the tool to your computer. It may open up another window or tab that prompts you to login first with your SUNet ID. Look in your normal downloads location (browser-dependent) to find and run the tool. You must have adminstrative rights on your computer to run the tool.

Inventory tag If you cannot get this tool to work, you can get help from our CRC consultants to change your power management settings. Put in a request on the HelpSU web site. Select Computers, Handhelds (PDAs), Printers, Servers from the Request Category drop-down menu. Then select Computer (desktop, laptop) from the Request Type drop-down menu. In the Request Description field, specify that you want to change the BigFix power management setting for your computer. Give the desired setting - one of Stanford Green, Stanford Yellow, or None. Include your building and room location and the number from the red and white CRC barcode sticker on the computer. That number begins with 0708... and looks like the sample to the right.

Why are we doing this?

The university has announced significant initiatives to reduce energy use. The School of Earth Sciences, as announced by Dean Matson, is committed to building sustainability programs. Implementing power management on all supported computers helps to achieve these goals in a convenient and effective manner.

Computers are a significant part of total energy use at the university. The goal of power management is to reduce this energy use when the computer is inactive or idle, while maintaining responsiveness when the computer is needed again.

Laptop users are familiar with these power management features because they are used to prolong battery life. By enabling power management all the time for all computers, we can significantly reduce energy use. The savings in our building electric bills can be applied to academic programs.

But I already have sleep settings on my computer. Why use BigFix?

Clearly, BigFix is a convenient and effective way to enable power management for those computers that are currently just left running all the time. But it also has advantages over manual settings that the computer user may have already enabled.

The BigFix power management program will make consistent settings for all supported computers in the School. This means that users know what to expect on any computer and the CRC support team can more readily debug any issues related to power management.

BigFix checks every day to make sure the power management settings are still in effect. This prevents gradual erosion of energy savings as users "temporarily" disable power management for a special reason, but then forget to put it back.

Finally, the BigFix program will report the power management setting of all computers in the School to a central console. This gives us a good way to measure how effectively we are saving energy on computer systems school-wide. There is no way to centrally measure individually set power management.

Comments or Questions?