Power management RRS feed

  • Question

  • I haven't played with WHS yet so if it already does what I'm asking for, please forgive me, and then let me know.


    I want the option of very aggressive power management to minimise power consumption. I'll be using WHS mainly for backup of my home PC and my HTPC, and also for archiving media for my HTPC (ripped CDs, recorded TV etc). I won't be running SMTP or anything else that absolutely has to be 24/7 apart from occasionally RDPing into my PCs from work. So, I want the WHS machine to go into S3 sleep whenever it's idle for more than about 15 mins


    To save power. Is the power management good enough (considering that WHS is based on the XP Sp2/2003 codebase rather than Vista, I imagine it isn't as flexible as Vista is)?


    I want reliable wake on lan from S3 (by IP rather than magic packet)... but will the client PCs continually wake up the server even if they are not actively using it?


    Can WHS spin drives down individually or does DE mean that all drives have to be spinning all the time? E.g could it be using a couple of drives for backing up important documents while powering down a big, greedy 1TB drive that has media files on it when no one is playing them?


    The point is - I can easily see that hundreds of hours of video, hundreds of hours of lossless audio and my ever growing collection of hi res photos could consume multiple 1TB+ drives. I want to keep all this stuff available, but I don't need it constantly enough to warrant >20W continous power consumption per drive, 24/7 for things that may only be accessed a few times a day. Waiting a few seconds for a drive to spin up or for the whole system to wake up from S3 sleep is OK though. What I definitely don't want to do is get up off the couch / my desk chair, and walk to the cupboard where I'll be keeping the server and drives, power it up, walk back and wait a couple of minutes before I can access the data. And then remember to go back and power everything down afterwards!





    Thursday, August 16, 2007 1:11 PM

All replies

  • Aitor, none of what you are looking for is enabled by default in WHS. Some of the items (Wake On LAN, in particular) aren't available at all, without third-party tools.

    Power management in WHS is basically the same as Windows Server 2003, so what you can do in that OS is what you'll hav available. You can configure it to go to S3 if your hardware supports it, but remember that both hardware and software can bring a machine out of S3, so it's possible that DE (for example) might wake the server every x minutes. You can configure it to spin down hard disks after a period of inactivity, but the drive and controller will have to support it, and software that accesses the drives regularly may interfere.

    As for Wake On LAN, There is, as I said, no support in the OS or in the WHS components, and there is no "WOL by IP". You'll have to configure the BIOS correctly, and you'll have to send a magic packet. That's how WOL works: you broadcast a magic packet and the hardware with that MAC address wakes up. If you configure the hardware to wake on any packet, it will wake up every time another device on your network sends any broadcast packet. (Which is normally every few minutes for a home network.)

    You'll probably get much farther in terms of power-savings by choosing your hardware carefully. With only a little effort, you should be able to get idle power consumption well under 60 watts. Possibly that, plus some judicious use of power management features, will get you to the point you want to reach.

    Thursday, August 16, 2007 5:33 PM
  • I did a quick search on the forums and I saw these articles on power consumption:


    1. Tranquil T7-HSA (UK) promises power consumption as low as 16W http://www.pcpro.co.uk/reviews/121499/tranquil-t7hsa.html


    Good luck!
    Saturday, August 18, 2007 4:56 AM
  • Ken, cmcarthy,


    Thanks for your replies!


    cmcarthy: yes, I'd read about the Tranquil already; I'm seriously considering it. (As luck would have it, I live in the uk). However, if I was going to use WHS for media streaming as well as backup, I'd probably have to hook up an external USB drive or two; some of these are better than others about spinning the disk down when idle. I don't want to be in the situation that I'm wasting 20W per external drive when I'm not actually using it! But as the main system unit is frugal, this will probably make more of an impact than having a greedier system and relying on S3, especially if Kens fears about the server continually waking up from S3 turn out to be true. Having said that, I don't think that going in and out of S3 or spinning the disks up is a serious problem for desktop drives. It IS an issue for enterprise class drives, which are very reliable if they are kept spinning 24/7 (I've seen SCSI drives last 4 - 5 years working flat out 24-7), but don't like being powered up and down all the time. But desktop drives and particularly notebook drives are designed to cope with frequent power cycling.


    Ken, I don't suppose you know if Windows can spin drives down individually? By "WOL by IP" I meant this:




    See the Advanced Properties for your NIC; it may support "wake up frame" for wake up capabilities as well as magic packet. Not all NICs / drivers support this. I've found that for machines that do, I can wake them up from S3 just by pinging them; you don't need to send a magic packet to a mac address. Generally I find that hostnames or IPs are easier to remember than MACs! I also found that attempting to browse a network share on a machine in S3 that had WOL set up like this also wakes it up. I guess mileage will vary depending on hardware and drivers though.


    I guess I will have to try WHS out to get some real world experience. I will also get in touch with Tranquil; in the past I've found their pre sales to be pretty good. As I will probably go for a quiet/silent, low power box like the tranquil, I may need external storage anyway, but maybe I shoud buy an external drive that can be switched over to being a standalone NAS drive just for media, if I can find a drive that has good power management. It's not something that most reviews touch on, unfortunately!


    Thanks again to both of you for replying!



    Saturday, August 18, 2007 3:03 PM
  • Hi Aitor,

    I've also read about the Tranquil but what makes me uncertain is that they only write about a 10/100 network interface.


    Sunday, August 19, 2007 6:28 PM
  • I set up WHS to spin down my drives after some idle time and it works perfectly. Although of course if the machine decides it wants to do some balancing, it's going to spin it back up again straight away. Listening to my machine ticking away on Sunday morning I heard a drive spin down, then back up again 1 minute later, then back down again after a couple of minutes, then back up again 1 minute later. I shall probably adjust the timings so it doesn't do this as much - I don't know if regular spin down/ups are detrimental to the lifetime of the drive.
    Monday, August 20, 2007 12:24 PM
  • I believe Tranquil has plans for devices that were designed from the ground up for WHS. Their first gen systems will be a modified version of the T7 which will require external drives if you want to go beyond one drive. I'm betting that their second gen devices will be very nice. Unfortunately for me the dollar is quite weak againt the pound right now so Tranquil may be out of my price range. I'll have to wait and see.
    Monday, August 20, 2007 3:22 PM