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Do Any Companies Power Down at Night?

An anonymous reader writes "My Health Sciences Campus has about 8,000 desktop computers, and on any given night about half of them are left on. I know this because I track all the MAC addresses in case there is a virus outbreak. Aside from the current fad of 'being green', has anyone had any success in encouraging users to power-down at night? You could potentially eliminate running bots, protect yourself from the next virus outbreak, keep your data safe, etc. Do security concerns and power consumption issues matter enough to do this?"

23 of 646 comments (clear)

  1. Hibernate by TheMeuge · · Score: 4, Insightful

    It's time that all large campuses configured their systems hibernate automatically, if left unused for 30 minutes.

    Really, there is no reason NOT to use the power management settings built into the OS.

  2. Re:Aside from being green... by Bwian_of_Nazareth · · Score: 5, Insightful

    The answer is simple. Tiny minority of the computers that are on could still be used by someone doing something important. You do not want to cut them off from the network.

  3. We have power down at night policy by ditoa · · Score: 5, Insightful

    I work for a large blue chip company and we have a strict policy of powering down at night (including monitor). We regularly audit the records to ensure the machine is powered down and users who are not are requested to always remember. A few users take a few reminders in order to do so and I have heard every excuse under for why they left it on and while some are valid the majority (95%) are not. Our reasons for pushing this policy is purely to save money and reduce unnecessary running time of the equipment. However we are in a position where only laptops users have VPN access so if they need to login to the network from home they already have their laptop with them. If we had open VPN access to desktop users I am sure we would see a lot of users leaving their computer on so that they can RDP into it over VPN.

    It took about 6 months before we were at a realistic level. We have 633 desktops on our site so there is normally always a valid reason for one or two to be left on (valid reasons being batch copy, verify or processing of files). For those interested we have had a reduction in the amount of equipment failure (HDD mainly) as well as pretty good cost savings for power. Not to mention running greener (which regardless of if you believe in global warming or not is good).

  4. Power vs. operational by Todd+Knarr · · Score: 4, Insightful

    I tend to leave the computer on overnight, but with things like monitor power-down and CPU idling enabled. When it's not doing anything it drops about 90% of it's power consumption after 15 minutes, and even when working with the monitor off (eg. running the nightly backup) it's still running at less than 50% of full power. If I power it off, by comparison, it can't run it's virus scan, backup, update check and the like overnight and has to do those things while I'm trying to use it during the day. Plus there's wear and tear to consider, I've noticed that the office computers that get turned off and on every day tend to fail and need replacing several times before mine (that stays on all the time) has a failure.

    So my preference is to leave computers running but with power-saving features set to minimize power without shutting things down. This means hard drives continue to spin but the CPU goes into low-power idle mode. The monitor goes to suspend mode (beam and deflection power is off but the circuits and coils are kept warm), not powered-down completely. That seems to be the best balance between reducing power consumption, allowing it to run maintenance operations overnight and minimizing wear and tear and thermal stress on the components. If management absolutely insists on ignoring those last two in favor of the first, wake-on-LAN is essential to allow nightly maintenance to happen.

    1. Re:Power vs. operational by edunbar93 · · Score: 4, Insightful

      Actually, leaving your hard drives on is the biggest source of idle-computer power drain. You can also set Windows to turn them off after a set period of time, say an hour of inactivity. It doesn't take long to spin them up anyway. Or you can set it to go into sleep mode, which does the same thing and more.

      Also, for the love of god, get an LCD. Modern LCDs are leaps and bounds better than CRTs in every way, especially power consumption. And they're dirt cheap too.

      --
      "No problem. I have the capacity to do infinite work so long as you don't mind that my quality approaches zero."-Dilbert
    2. Re:Power vs. operational by toddestan · · Score: 3, Insightful

      Also, for the love of god, get an LCD. Modern LCDs are leaps and bounds better than CRTs in every way, especially power consumption. And they're dirt cheap too.

      So long as that CRT still works, it's better for the environment just to keep using it. The added electricity usage is far less than the energy and environmental costs of properly disposing of that CRT monitor, not to mention the environmental and energy costs of producing the replacement LCD.

    3. Re:Power vs. operational by Todd+Knarr · · Score: 3, Insightful

      Your point #1 is false, I'm afraid. Yes, the components were designed to work over a wide temperature range. The problem is the change. Gradual or not, components made of different materials expand and contract at different rates as temperature changes. As long as the temperature stays steady, regardless of what that steady temperature is, there's no problem. But if it's changing, even slowly, then the different materials want to change size relative to each other. That produces stress. You can see this in the thermostat that controls your home's heating and cooling. It's made of strips of 2 metals with drastically different thermal expansion ratios bonded together. As the temperature changes, the bimetallic strip physically warps. The same thing happens inside every chip and solder joint in your computer every time it warms up or cools down. And eventually those joins start to crack apart. That does two things. First, it increases the electrical resistance of the joint. Higher resistance = more heat. Second, it disrupts the thermal transfer from the chips themselves into their carriers by disrupting the tight physical contact between them. So now the chips aren't being cooled quite as well, and at the same time they're running hotter internally. All that turns into a shorter lifespan.

      As for #2, not anymore. That surge effect's confined to the power supply itself. It still affects the PSU, but no worse than normal power-line noise will. The big effect is actually on the drive motors and bearings. Stopped, the bearings settle a bit. When the platters are spun up, it takes a moment for the bearings to lift up on their film of lubricant again. One cycle like that puts as much wear on the bearings as many hours of steady spinning. And the power cost of keeping a drive spinning is minimal. Think about spinning a wheel, which is all the drive's platters are. It takes a fair amount of effort to start a heavy wheel spinning and get it up to speed, but once it's going it takes very little effort to keep it spinning at that speed. It's enough on my large drives that I can actually see the spike in power draw at the wall socket when a drive is spun up from a dead stop.

      When people comment about how their machines aren't having problems, I'm often a bit skeptical. I've had quite a few people ask me for help with a computer that "just started having problems a few days ago". When I throw my hardware diagnostic program at it, I get a veritable flood of red malfunction and error indications. On the last one, "Every now and then it won't boot, and occasionally a program dies for no reason." turned into having to replace the motherboard and all the RAM (every stick of memory had at least 2 bad columns, and the EIDE controller was fried and corrupting data during large DMA transfers) and restore the entire system from original media and backups (losing about 10% of the data in the process, the backups didn't go back far enough to contain uncorrupted copies of the files).

  5. I used to turn my machine off at night ... by LaughingCoder · · Score: 4, Insightful

    ... but now IT has loaded so much crap on it ("desktop agents" [ie apps that spy on me], antivirus, patches, etc) that it is fully 15-20 minutes after turning it on before it is usable. So now I never turn it off. I did the hibernation thing for awhile, but then it stopped working for some reason and I haven't been able to fix it. And if I ask IT to fix it, their solution is always the same for every problem - wipe the machine - a tad inconvenient for me, but pretty efficient for them I suppose. Sigh.

    --
    The more you regulate a company, the worse its products become.
  6. Re:Why power down? by mollymoo · · Score: 4, Insightful

    Energy consumption is a non-issue. We don't pay much for electricity.

    Reducing energy consumption isn't just about saving money, it's about not fucking up the planet too.

    --
    Chernobyl 'not a wildlife haven' - BBC News
  7. Re:Common wisdom by Planesdragon · · Score: 4, Insightful

    Common wisdom (which may or may not be actual wisdom) suggests that powering up/down of computer power supplies is one of the largest sources of "wear" on computers nowadays, and so it's best to avoid that Nope. That would only be true if all of the three are true:

    1: Power-cycling actually reduces the MTBF opposed to just leaving it on.

    2: The reduced MTBF is lower than your company intends to keep the asset.

    3: Cost-savings from the "increased" MTBF by leaving it on is greater than the electricity (+ increased A/C cost) cost to run those 300W power supplies all the time.

    Of the ~6 computers I've had to failure, they all lasted far longer than even a five-year technology plan, AND did not fail due to simple wear and tear on the circuits. My anecdote isn't data, but it does make me question your conventional wisdom. (Especially since those PCs I know that are left on all the time don't have a significantly increased lifespan.)
  8. Re:We power down at weekends by Albanach · · Score: 4, Insightful

    What's the cost of 10k * 261 days * 12 hours of power?

    Surely you could use wake on lan to wake the machines then do your rollout 10 minutes later? Or do a patch install when the machine is turned on and connects to the domain controller?

    In windows I'm sure you can set the time between warning appearing and shutdown ocuring. Give 600 seconds warning and you could probably shutdown 90% of the machines overnight.

  9. Re:Why power down? by Creepy+Crawler · · Score: 3, Insightful

    Unfortunately, "fucking up the planet" as you so eloquently put it isn't in the books as a cost.

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  10. Re:Create job to force automatic reboot or shutdow by dustmite · · Score: 4, Insightful

    Someone might be using it ... there are always a few late users. Trying to determine if a computer is in use in order to shut it down isn't always that simple.

    I suggest a simpler, low-tech solution - just stick up visible signs in the labs, and on some of the major office floors, asking people to shut down the computers in the evenings ... it won't be a 100% solution, but most people would probably comply, so for the comparatively little effort put in I bet you can hardly get a better return.

    Just the energy savings on that many computers would be not insignificant.

  11. Re:We power down at weekends by jimicus · · Score: 4, Insightful

    In windows I'm sure you can set the time between warning appearing and shutdown ocuring. Give 600 seconds warning and you could probably shutdown 90% of the machines overnight.

    You're assuming that 100% of machines in use are doing something interactive (and therefore have someone sat at them). This is frequently not the case.

  12. Re:workstations by day, cluster by night by anno1602 · · Score: 4, Insightful

    Well, in a university, "scientific calculations" could mean actually running simulations/models/whatever, that is, things for which you would normally use some super computer. So it is not necessarily a question of "getting away with this", it might make perfect operational sense and boost the uni's available computational power and thus productivity. Depending on what industry you work in, you could do a similar thing in a company, for example a nightly distributed build-and-extensive-regression-test in a software shop, and save on purchasing and operating dedicated computers. There are lots of quite productive uses for distributed computing. You just need to think about what your company might do with it. Of course, if there is no productive thing the computers could be doing, they are better turned off.

  13. Re:Aside from being green... by Kjella · · Score: 4, Insightful

    Amen to that. I doubt anyone really wants to pull an all-nighter, they're there because there's a deadline coming or a problem that must be resolved right now. And whether true or false, the first time anyone uses the excuse "Well, I was ready to pull an all-nighter but from 10pm the network was down" the IT department will have their ass chewed out. PCs inactive -> PCs hibernate is ok, but even then you need a simple way to disable it. On several occasions I've visited copmanies that had boxes which were "don't touch - accessed remotely by VPN" where the user couldn't just unhibernate it in the morning. Plus funny stuff like updates, virus scans and backup (if applicable) that probably runs at some ungodly hour which means you need to wake them first or lose most of the downtime, run those and put them back into sleep. Sure, maybe you could get every PC do to this reliably but I think the administration and scripting of that will cost you quite a bit.

    --
    Live today, because you never know what tomorrow brings
  14. Re:Why power down? by NeverVotedBush · · Score: 3, Insightful

    I'm sorry you're not too.

  15. Re:Easy fix by hedwards · · Score: 3, Insightful

    One which is properly managed. It is a very bad thing when working nights and weekends is the thing to do. Except in a global situation where 2 in the morning at the work site might be noon where the worker is, or it the workers do most or all of their work at night. If it's just a matter of accessing some work files, that's what the fileserver is for, it makes far more sense to figure out how to set that up securely, than to hope that every one of a potentially huge number of computers is secure enough to access from offsite.

    Encouraging people to pull all nighters or work on weekends smacks of an inefficient workforce or ineffective management. The only times people should be working those hours are because a job sprang up last minute due to an act of god or because the work requires that it be done when people aren't around. And in those cases if you've got on sight IT, it shouldn't be that difficult to set up an arrangement to cope with that. If you're going to have work done nights and weekends anyway, you may as well just outsource things to another timezone, and that's frequently a cost saving thing anyways.

  16. Re:Common wisdom by toddestan · · Score: 3, Insightful

    I find that powering on a system is an excellent time to catch things that are starting to fail. I'd much rather catch the harddisk when it's starting to have issues spinning up and replace it then, as opposed to finding out the harddrive is a brick when I try to start up a computer that was just shut down after months of being on. It's been a long time since I've lost any data on a harddisk that was regularly powered down. Furthermore, I've also found that drives that are only run a few hours a day outlast drives that are run 24/7 anyway.

  17. Re:Create job to force automatic reboot or shutdow by ATMD · · Score: 4, Insightful

    Why not just have the machine shut down automatically on logout if it's between two specified times (eg. 9pm and 8am)?

    --
    Nobody else has this sig.
  18. Re:Uh, Sleep Mode - shutdown? by brain159 · · Score: 5, Insightful

    The student who walked away from (or, fell asleep at) the PC without saving learns a valuable lesson.

  19. Re:viruses by Anonymous Coward · · Score: 3, Insightful

    Because "virii" is retarded from any angle. If you want to make up a "smart" sounding word use "viri" instead. It's still wrong, but it's less idiotically wrong than "virii". "Viri" at least has some logic to it, like "Vaxen". Imagine if some idiots had pluralized "Vax" as "Vaaxen". It's wrong and makes no sense.

  20. Re:Create job to force automatic reboot or shutdow by camperdave · · Score: 4, Insightful

    In a corporate environment, that sort of decision is made at a corporate policy level, and not at an IT personnel level. Nobody would get fired.

    --
    When our name is on the back of your car, we're behind you all the way!