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Power Management and Networks?
ChamaraG asks: "Do you enable power management in your desktop PCs, and have you had any problems with networking after enabling power management (problems like losing open network connections, network using applications hanging after resuming from low power states, etc)? To clarify, by desktop PCs I mean PCs compliant with ACPI and Wake-On-LAN and capable of resuming from low power states in a few seconds, so that waking up time is not an issue. I am interested in the energy efficiency of networks and networked devices and I would like hear of problems that you might have had. Some applications I have tested will disable power management settings, presumably in order to maintain network connectivity. Surveys by the Lawrence Berkeley National Laboratory show that less than 5% of desktop PCs in offices are in low power states at night (36% - off, 60% - on). So, do you enable or disable power management in your PCs? If power management is disabled, what prompted you to do so and what would make you enable power management? What connectivity related problems did you encounter after enabling power management?"
Considering modern ATX power supplies common to most desktop PCs, wouldn't "off" be considered a "low power state"? (ATX power supplies use a small amount of current even when the computer is off, unless the power supply is plugged.)
In that case, the stats will be that roughly 40% of desktop PCs are in a low power state at night.
For XP Home edition on Dell computer: No deep hibernation allowed (computer won't wake up), no Ethernet card power down allowed (always loses the connection and has to be restarted). Everything else seems to do ok. Monitor going to sleep is good (saves screen, saves heat, better screensaver than some silly graphic acrobatics and no wasting cpu cycles). Hard drive spin down is ok as long as it doesn't happen too fast (at least one hour of inactivity). Of course, running SETI or some other background community software means your computer can't sleep.
FYI, the statistics in the report do not include home computers.
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If power management is disabled, what prompted you to do so?
Some of them are servers. The rest run Folding@Home.
and what would make you enable power management?
Being completely unable to afford not to. We've got quite a ways to go before energy becomes that expensive.
I hate idle computers, and by definition a computer in power-saving mode is idle.
Random and weird software I've written.
We schedule our WSUS (MS Software update services) to run at night so as not to bother the user. We also run quite a few machines with Deep Freeze, and they require a "Maintainence Mode" in order to unfreeze and apply updates.
My Staff are also becoming addicted to running Remote Desktop, so they won't let us control when the machines are turned off.
Most new staff ask me what they should do with their PC at night, and I always feel guilty when I tell them that it doesn't matter to me, and they might just leave it on. (Even if they turn it off, it auto-ons itself at 4:00 a.m.)
I'm always using my CPU, so I don't want it to go into low power mode. I support the Folding At Home and IBM's World Community Grid projects.
Even if I wasn't, I'm often still using my CPU for keeping Azereus running (Fedora distros).
I don't want it going offline. I want it doing my bidding full time.
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At my job, we have all the servers & workstations configured to run 24/7, for several reasons.
On each computer, scheduled jobs (cronjobs on Linux & OSX, scheduled tasks on Windows) do things like backups, updates, antivirus & antispyware scans, etc. Making these things happen automatically and outside of business hours makes life much easier for the people that have to maintain all these systems (i.e. me). The main downside is that occasionally an operating system will force an unattended, unprompted reboot, causing the owner of that workstation to lose work. This is annoying, but we warn people in advance that it could happen, and they need to save their work before going home; the alternative -- manually finding out about & doing these updates machine by machine -- just isn't tenable.
The other benefit though is that we have SNMP monitoring of all hosts throughout the day. If a machine is having a hardware problem -- say, the printer is running out of toner, or someone's hard drive is filling up -- we get alert emails about it so that the problem can be fixed. This also allows us to know what machines are down at any given time, and have a reasonably small window indicating when it went down and when it came back up; this can help narrow down time frames for events like office power outages or, should it happen, the theft of a workstation.
I suppose we could get some of these benefis while also providing nightly downtime, but the benefits of having continual monitoring & maintenance are strong enough that there hasn't been a lot of call for it -- and when someone brings the idea up, the proposal usually gets shot down by the people managing the network.
If it were possible to bring this equipment into some kind of standby mode where it was still possible to do basic network tests (continually pingable, occasionally query for things like disc space, once-nightly wake up for updates & virus/spyware scans, etc) then maybe the idea would fly, but as things are now, there doesn't seem to be a good way to get these benefits other than by just leaving everything on all the time.
If nothing else, at least the monitors get turned off when they go idle...
DO NOT LEAVE IT IS NOT REAL