S3 Standby State Done Right

For Earth Day, Cameron Butterfield has written in with a pointer to his article on how to get your Windows PC into S3 sleep, and why you want to. It covers the question of how to take advantage of this extremely low-power mode even when your machine is an "always on" file server, remote desktop, or VNC server.

And Linux?

[Ed Avis (5917)]

Great for Windows users... but what are the options to set up a Linux system to reduce power usage and fan noise when idle?

Re:And Linux?

[BACbKA (534028)]

Gentoo's Power Management Guide [gentoo.org] is a bit gentoo-centric, but most things carry to another distribution easily.

Re:And Linux?

[rduke15 (721841)]

See this article: Debian HOW-TO : CPU power management [technowizah.com]. I used the info to configure a couple of Poweredge 860 server. Most of the time, it's at a CPU speed of 300Mhz instead of 3 Ghz. That saves quite some power, and you cannot notice the difference in speed.

Re:And Linux?

[BillGatesLoveChild (1046184)]

> what are the options to set up a Linux system to reduce power usage and fan noise when idle?

Disconnect those pesky cooling fans. They just make a lot noise and suck up power. Truth is, your PC will run fine without them. It's just a scam by equipment manufacturers to make a few extra bucks out of you. I've been running with them removed for years, no problems.

regards
Scott E. Brown
NOAA Antarctic Station

Re:And Linux?

[Thomas Shaddack (709926)]

A way to make a computer quieter is replacing the smaller fans with somewhat bigger ones, and slow down their rotation (eg. with a suitable series resistor). The aim is to get comparable airflow over the heatsink with lower fan blade speed, which means less turbulence over them, which means much less noise.

Re:

[flyingfsck (986395)]

Here you go:
service syslog stop
hdparm -B 1 /dev/sda
hdparm -S 5 /dev/sda
echo 5 /proc/sys/vm/laptop_mode

Re:

[Asztal_ (914605)]

You realise that would be finished in 15 seconds and then you could put it to sleep, right?

Nice FUD

[The Bungi (221687)]

Anything M$ touches is shit

Oh yeah.

Bill Gate's memo

That's an interesting email from 1999. Myself, I've been known to send emails to the tone of "how can we prevent the competition from leeching on our multi-million dollar R&D investment with our technology partners", but OK.

Would you like to point me to the follow up email from Eric Rudder that says "Hi Bill - As you requested, we've made the ACPI extensions specific to Windows so no one else can implement them. Cheers!" I can't seem to find it.

Oh, wait - here's ACPIfor Linux [sourceforge.net] and ACPI for FreeBSD [freebsd.org]. Indeed, here's a quote from the WP entry:

The Advanced Configuration and Power Interface (ACPI) specification is an open industry standard first released in December 1996 developed by HP, Intel, Microsoft, Phoenix and Toshiba that defines common interfaces for hardware recognition, motherboard and device configuration and power management.

Now, ACPI has its shortcomings. It's complicated. It might not be your ideal of a standard. But it is an open standard, which Linux indeed implements. It might be broken in some ways in Linux as it is in Windows, but implemented it is. It's an important standard because it takes hardware out of the equation, which is important for a general OS that's supposed to support a wide range of it.

I still use APM for the most part

Really? That's also a Microsoft-defined standard [wikipedia.org] (along with Intel):

Advanced Power Management (APM) is an API developed by Intel and Microsoft

Is that standard "shit" as well? And if you all these standards from Microsoft are "shit", then why do you use them at all? You use Linux, right? Why don't you come up with your own standard and give it to the free software world so they can stop using all these "shit" open standards that Microsoft has bothered to make open for anyone to use? Which reminds me, I'd love to see that other email about ACPI I mentioned. Thanks.

Re:

[xenocide2 (231786)]

Unfortunately, the world is far more complicated than you'd like. Matthew Garrett has [livejournal.com] extensively [advogato.org] about the subject. Truth is, ACPI a standard that nobody follows intelligently. Garrett writes about how part of the spec involves an interpreted machine code called DSDT (this already sounds like a recipe for disaster) that is used to guide actions. The problem is two fold:

• DSDT's are buggy (go figure)
• The common method for fixing a broken DSDT is to patch it after the machine has booted via some driver

Micros

Re:

[xenocide2 (231786)]

That post looks a bit screwed up that I made, but he's a central member of Ubuntu, a member of the laptop, kernel, and acpi teams and one of 4 members of the technical board. I had hoped his insightful analysis would have been enough, but it seems I botched a link or two. To make up for it, here's a video [linux.org.au] of him detailing how hacking acpi is done.

Re:APM Sucks too.

[The Bungi (221687)]

Oh twitter, you're going to love this. Here's an article [advogato.org] by the guy that actually writes this stuff for your operating system. I'd like you to go through that article and please share with us where the guy that actually writes the stuff blames Bill Gates or "M$" for how ACPI works (or not). As opposed to just the general sense of "this stuff is hard" I get from it.

Once you're done getting an education, I'd like for you to explain how "M$" allegedly sabotaged ACPI on Linux. You pointed [slashdot.org] to an eight-year old email from Bill Gates that, if anything, proves Microsoft did not do anything to impact the implementation of ACPI in Linux. Seriously, just in case your FSF distortion field is turned up too high, that's exactly what you are proving by linking to that email. You have ACPI in Linux. It might be as broken as it is on Windows, but you have it. You realize that, yes? God, please tell me you realize that?

Re:

[Achromatic1978 (916097)]

Generally people don't bother to refute the content of his posts because it's pointless. He'll argue until he's blue in the face - or you provide a coherent and logical response to him. He has no rebuttal for that. Far easier for him to go on to the "Evil Micro$oft WinDoze!" troll.

Also available on Linux

[by Anonymous Coward]

It doesn't seem to be a hot topic because I couldn't google a definitive page. There were lots of pages for individual computers or distros though.

The documentation is probably on your own computer at: /usr/src/linux/Documentation/power/ ... The exact file on my system is states.txt but it also seems to exist on other distros as suspend.txt

Laptops?

[Vo1t (1079521)]

I wonder if how does S3 work on a laptop? Does laptops' built-in energy saving mechanism collide with tricks described in the article?

Re:

[Southpaw018 (793465)]

Most laptops come preconfigured to take advantage of most of the stuff in the article, though it wouldn't hurt to check. The last few new Dell laptops we've purchased at my organization default to S1 after a few minutes, S3 if you close the lid or hit sleep, and S4/S5 for shutdown.

S3 and MCE

[gEvil (beta) (945888)]

I use the S3 standby on my MCE machine, and it's really really nice. I turn the machine on and off (well, awake/asleep) using the power button on the remote, and the machine is up and ready to go in about 3 or 4 seconds (as long as it takes me to switch the TV to the right input). I've only ever had it refuse to wake up once in the 1-1/2 years I've been using it, and that was remedied by using the power button on the front of the machine (it woke right up and didn't even need to be rebooted). Definitely worth looking into for instantaneous access + decent power savings.

Re:S3 and MCE

[MSRedfox (1043112)]

Under MCE, I use the MCE Standy Tool. MCE has a bad habit of waking up to record a show and then not returning to standby afterwards. This can result in the computer staying on all day instead of just 1/2 hour to record a small show. The Standby Tool has features to help MCE handle power management in better ways then Windows default methods. It makes me wonder why Microsoft couldn't get things to work as smoothly as this 3rd party software. http://www.xs4all.nl/~hveijk/mst/indexe.htm [xs4all.nl]

network broadcast traffic

[by Anonymous Coward]

Surely enabling your PC to wake up whenever any network traffic is sensed is stupid in the example described in the article.

Will it not wake up whenever any workgroup broadcasts are sent to it?

Re:network broadcast traffic

[Bozzio (183974)]

yes it will.
Or it does for me. Even if the computer is alone on the router. It seems my router occasionally broadcasts something and wakes up all my computers.

I've switched to using the magic packet alternative. The only problem is that since my server PC is behind my router, I have to SSH into the router and sent the magic packet from there. ICKY.

I hear other routers (mine is a Linksys WRT54GS) will let you WOL remotely. Normally, you just send your magic packet to the router and set up the router to convert it to a broadcast.

If I remember correctly, a magic packet is just a packet with the correct header and the client's MAC address broadcast to the network.

FreeBSD

[evilviper (135110)]

I know I'm setting myself up for flames around here, but the OS with the best support for APCI S3 Suspend is FreeBSD 6.2, even though it's certainly not perfect.

My desktop _almost_ worked. I had to swap-out my ATI video card to get it to resume from S3.

Now, the big problem is X.org... Since X doesn't play well with suspend, FreeBSD is supposed to switch off of X, to a virtual console before entering suspend mode. Unfortunately, I've found that, unfortunately, X 6.9.0 freezes about 1 in 3 times. Once I figured that out, it was just a matter of manually switching to a console, then typing "suspend" before I walk away. Now I haven't rebooted my machine in months, and it's on and usable (right where I left everything) in about 3 seconds.

Of course, the drawback to X not cooperating is that I can't set my machine to auto suspend when it's been idle for a few minutes, but I'm hopeful the next release of FreeBSD will fix that. X6.9.0 is the latest ported release, and compiling from vanilla sources goes horribly, horribly wrong, right now. I could try downgrading, but it's not worth the hassle and lost features, IMHO.

Re:FreeBSD

[value_added (719364)]

I know I'm setting myself up for flames around here, but the OS with the best support for APCI S3 Suspend is FreeBSD 6.2, even though it's certainly not perfect.

Perhaps, but the issue is a lot more complicated than that. We're talking about the BIOS, the OS, and then how the two relate to each other. That said, it doesn't suprise me that the article is lame. Setting a fixed IP address and making use of WOL? What's that got to do with Windows, and what does "done right" refer to?

The only informative (and amusing) bit was the Microsoft chosen USB behaviour (hidden) that requires an "easy" registry edit to change. So much for "Oh, no, not manually editing a config file!" I guess having all the behaviour and options explicitly set forth and easily editable is the wrong approach. ;-)

X.org... Since X doesn't play well with suspend, FreeBSD is supposed to switch off of X, to a virtual console before entering suspend mode. Unfortunately, I've found that, unfortunately, X 6.9.0 freezes about 1 in 3 times. Once I figured that out, it was just a matter of manually switching to a console ...

I'm going by memory here, but IIRC, that's handled with a sysctl. You shouldn't need to manually do anything. Read through acpi(4) and then Google for more info, or better yet, just search the 'mobile' archives for some possible settings and the merits of each.

Of course, the drawback to X not cooperating is that I can't set my machine to auto suspend when it's been idle for a few minutes, but I'm hopeful the next release of FreeBSD will fix that.

I'm not sure you want an S3 state every few minutes. It would make more sense to blank the screen (and kill the backlight on a notebook) by setting the DPMS option in xorg.conf, and set your screensaver options in .Xdefaults. The CPU can be trottled using any number of methods either on a dynamic basis, or at set time. Throw ataidle into the mix and you've got most everything you need for those "every few minutes' intervals. How many more options could you want?

For a full suspend after x minutes, why not script your own approach? One option would be to use xscreensaver-command to invoke a count-down timer to invoke zzz(8)? Or if power usage is a Really Big Deal, make use of WOL and start/stop the system at set times. Dunno if that would work for a desktop system, but it might cut down the hours on /.

Re:FreeBSD

[by Anonymous Coward]

Guys! You found each other!

Shouldn't you guys exchange phone numbers or something?

Re:FreeBSD

[evilviper (135110)]

S3 mode is entered by running "acpiconf -s 3"

All available options can be listed by running "sysctl -a hw.acpi" and included in /etc/sysctl.conf to be automatically set upon boot-up. Basically you'll only need "hw.acpi.reset_video=" set to 0 or 1 depending on your system.

If you need to unload modules or any other action before suspending, see /etc/rc.suspend. Put the opposite commands in /etc/rc.resume.

That should be everything you need. Either your hardware will work, or it won't. In the latter case, strip your system down to nothing but video, and try different video cards. Then add a piece at a time to see what's causing problems.

dumppo.exe the Microsoft Power Tool

[MSRedfox (1043112)]

Windows XP will often times not give s3 suspend as an option even when turned on in BIOS. But with Microsofts dumppo.exe utility you can force it to use an S3 or S4 state. ftp://ftp.microsoft.com/products/Oemtest/v1.1/WOST est/Tools/Acpi/dumppo.exe [microsoft.com] To force it to S3, run this under command prompt "dumppo admin minsleep=s3"

Re:dumppo.exe the Microsoft Power Tool

[ergo98 (9391)]

I wrote about the power consumption of S1 versus S3 sleep [yafla.com], and as you mentioned dumppo.exe was the enabling-tool that let me take advantage of this great bit of functionality.

The biggest downside of S3 sleep is that about 1 out of every 200 recovers or thereabouts it completely fails to come back, thought that's probably a mainboard issue more than an OS or technology issue.

Oh, and a great little helper app if you use S3 is WakeUpOnStandBy [dennisbabkin.com]. It allows you to configure a machine to "come alive" at scheduled times, even from an S3 sleep (apparently the BIOS supports configured wake-up times, and this app knows to tell it to wake up accordingly just as going to sleep). Very helpful little app -- I have my PC set to come alive in the morning when I know I'll be remoting in.

Oh, and rather than waking up on all network traffic, as the article recommends, it's far better to wake up on WakeOnLan packets. There are lots of resources out there for that.

want a "file transfer" powerdown mode.

[plasmacutter (901737)]

often, my computers cant be put to sleep because theyre transferring files (over aim, bit torrent, you name it.. every app according to its need).

Ive noticed all companies, including apple, whose products i use, are giving you only a black and white choice. you either have the computer awake or its fully asleep.

i'd like to have a low power transfer mode, where the cpu is reduced (to 1 core at say 500 mhz), the monitor is turned off, and as much memory as possible is dedicated to the apps which are doing intensive file reads/writes. this will allow the hard drives to be used less by caching the files in ram and pulsing the hard disk.

Re:

[evilviper (135110)]

i'd like to have a low power transfer mode, where the cpu is reduced (to 1 core at say 500 mhz),

Thanks to AMD's CnQ, and Intel later following suit, any CPU made in at least the past year (and more for AMD64 CPUs), will idle down to low power states automatically.

the monitor is turned off,

Also easy. You can hit the power button on the monitor, you can wait for it to automatically shut off after 15-20 minutes, or with X11, you can run xset and tell the video card o shut-off the monitor.

and as much memory as

Re:

[ivan256 (17499)]

You need to write to the disk every few seconds, to maintain a consistent state, with or without a journaling file system.

No you don't, and in fact if you mount your filesystem read-only, or noatime, and run noflushd your hard drives can spin down indefinitely as long as your dataset fits in memory. I used to get 8-9 hours out of the battery on my PowerBook G3 using this method and low screen brightness.

Of course, if you are writing to files and you do this and then lose power, you lose data... But you c

Re:

[ivan256 (17499)]

noatime prevents reads from making journal transactions which spin up the disk. If you're serving static files (I.E. Reading only), you can mount noatime and prevent the disk from spinning up once all the data you're serving is in memory.

Another old trick, which I still use regularly, is to copy all the data you're serving into a ramdisk or a tmpfs, and then unmount all disk based partitions. Turn on PowerNOW! or SpeedStep, force the CPU multiplier low, and you can serve thousands of pages per second for un

Re:

[evilviper (135110)]

you should never end up with a corrupted filesystem.

Hate to tell you, but that's exactly what happens. You can't guaranty file system consistency when doing out-of-order writes. That's among the main reasons Ext3 does a full "fsync" every 6 seconds. It's a serious limitation of Ext2 in it's default mode. You're simply playing Russian Roulette with your data, and eventually you'll lose.

You certainly don't have to take my word for it. It's a well known issue, and there are several write-ups of it.

Re:

[Graff (532189)]

plasmacutter had this to say:

Ive noticed all companies, including apple, whose products i use, are giving you only a black and white choice. you either have the computer awake or its fully asleep.

i'd like to have a low power transfer mode, where the cpu is reduced (to 1 core at say 500 mhz), the monitor is turned off, and as much memory as possible is dedicated to the apps which are doing intensive file reads/writes. this will allow the hard drives to be used less by caching the files in ram and pulsing th

Re:

[gbjbaanb (229885)]

Obviously, it takes more energy to spin a disk all week than it does to power it down for a read on monday morning and a write on friday afternoon. I don't know exactly at what point is it more cost effective? I generally use 1hr in the power save box before the drive is spun down. However, the OP wanted to 'pulse' the HDD, basically keeping it powered down until it was needed which would be terrible for energy use.

Bear in mind that big, fancy SCSI arrays on big boxes have special circuitry to bring the dri

thanks!

[hansamurai (907719)]

Wow, great article and definitely something I wouldn't even consider unless it discussed wake-on-lan settings as I use my computer as data storage for my media center also. I tested out my standby settings and my fans just kept going, which is a problem for me because right now my office is 9 degrees hotter than the temperature outside (80 to 71, in Minnesota!). Kind of uncomfortable. Also nice to see an article all on one page. I expect to see a regurgitation of this article soon on some ad-ridden PC s

What about wireless ?

[Qwavel (733416)]

There was some useful info in this article about configuring your network adapter to support wake-on-lan, but what about wireless adapters? In my experience they don't seem to support WOL or any equivalent. The only solution I can think of is to connect an ethernet client device to my computer so that I can use the WOL of the computer's ethernet, but this is not really a good solution.

Is there any sort of WOL capabilities in the new 802.11n?

Re:

[Guy Harris (3803)]

There was some useful info in this article about configuring your network adapter to support wake-on-lan, but what about wireless adapters? In my experience they don't seem to support WOL or any equivalent.

At least at one point, I found one 802.11 adapter or chipset that supported OnNow-style [microsoft.com] wakeup, but I don't know whether drivers supported that.

You'd have to keep the radio on, though, which means there's some power you can't save.

Is there any sort of WOL capabilities in the new 802.11n?

That's probably

Bad Assumption

[by Anonymous Coward]

* I calculated (24 hours per day) * 30 days a week [sic] = 720 hours
* Power bills are generally measured in kilowatt hours or "kW/h"s. Power rates might be as much as $0.12 per kW/h
* Our total cost of having the computer on 24/7 for the month in this scenario would be as follows:
* .4 kW (400watts) * 720 Hours * $0.12kW/h = $34.56

The 400 watts per hour is a really poor assumption. First, the average home PC wouldn't use 400 watts at peak, let alone continuously. Secondly, the 400 watts would almost never be continuous. Even a PC left on overnight will use far less power then one being actively used during the day. My power costs almost $0.11 per kilowatt-hour, and I have a power bill during non-summer months (damn AC) of about $45-$55 dollars with two desktop computers running 24/7. I honestly wouldn't be surprised if most of this came from my computers, but it certainly isn't as much as the article makes it sound.

That said, it is a good article on how to keep the "instant-on" without using excess power.

Re:

[TheThiefMaster (992038)]

It depends on the power supply. The cheap ones can be as bad as 50% efficient, in which case a 200W pc would draw 400W from the wall.

Incidentally I have two PCs (with >85% efficiency PSUs) and a 19" CRT monitor plugged through a power-meter right now and they are drawing 510W total, and 425W if I turn off the monitor.

One of the PCs is a dual socket A machine with cpus that won't go below 60C despite some really powerful air cooling, and the other is an AMD A64-X2 3800+ with ATI X1900XTX. Both are fairly

Calculations are a bit off

[bogie (31020)]

"If we take just a reasonable estimate that a computer uses 400 Watts idling along, we can find some astounding figures."

That doesn't sound very reasonable to me.

".4 kW (400watts) * 720 Hours * $0.12kW/h = $34.56"

Nope, that's way off what the average PC costs to run.

He does have a point thought about using lower power modes. On newer PCs it seems to work well and it will save you bucks if you have several PCs in your house.

Re:

[pimterry (970628)]

I have a power monitor thing on the socket for my home server (it's just a box, no screen keyboard etc) and right now it's using 132 Watts downloading torrents and web serving (mostly as a web dev test site, so probably not really doing any work). It's a 3Ghz P4 too, so it's probably not as power efficient as it could be.

400 watts has got to be way off.

400 watts is high

[jbengt (874751)]

I work as an HVAC engineer, and I have to take into account the PCs when designing air conditioning for an office. I figure 200 to 250 watts per workstation; that is supposed to take into account average usage including everything: the PC, monitor, peripherals, task lighting, occassional printers, etc. I've been told that this is too high, but my career has spanned a lot of changes - dummy terminals, energy inefficient monitors, heavy duty PC workstations, efficient but larger monitors, LCD monitors, thin

Re:Calculations are a bit off

[Michael Woodhams (112247)]

Those 600+ W power supplies are purely for people with inferiority complexes about other aspects of their lives/bodies. Here's [silentpcreview.com] a discussion about how much you can run on a 300W PSU. 300W suffices for a modern high-end CPU plus high-end GPU plus a bunch of drives, when under heavy load. Even a high end system will idle at around 150W. A more sensible system is probably idling around 80W.

NOTE: All the figures above are *not* including losses in the PSU. A modern PSU should be about 7 5% efficient, so increase the above by 1/3 to make them comparable to the 400W number in the article.

Re:

[Michael Woodhams (112247)]

There is a problem that nobody seems to be interested in producing good low capacity PSUs. If you want (say) 80% efficiency and modular cabling, most manufacturers don't have anything below 500W. (A few have 400W.)

Some good options now are Seasonic S12, Antec NeoHE, Silverstone ST30NF, Nexus NX-80x0 series.

My weeks only have 7 days in them.

[QuietLagoon (813062)]

From the article: I calculated (24 hours per day) * 30 days a week = 720 hours

Does that mean my PC costs one-quarter of what he calculates?

Re:

[flyingfsck (986395)]

It means that he is a consultant and bills per hour and that is what he bills per week...

What an opening

[LordSnooty (853791)]

Because of increasing awareness in the general public about energy conservation, the ability to utilize low power states on desktop PCs is incredibly underdocumented and widely unused.

The opening sentence fails to compile in my logic parser - there is little documentation because of increasing awareness? Better would have been: "Because of increasing awareness in the general public about energy conservation, people want to know more about the ability to utilize low power states on desktop PCs. What they're finding is that it's incredibly underdocumented and widely unused." Oh, and "underdocumented" doesn't appear to be a word.

Welcome to the exciting new world of UGC.

re: S3 Standby State Done Right

[AncientPC (951874)]

Slightly off tangent, but hibernation (S4) fails in WinXP SP2 if you have more than 1GB of RAM. [microsoft.com]

My biggest problem with standby on my WinXP machine is that my machine will randomly wake up after a random amount of time. I've already disabled WOL and Wake-on-USB, but my computer will wake up randomly from standby anywhere from 3 minutes to never. I still can't figure out what's causing the problem. :(

Re: S3 Standby State Done Right

[bi_boy (630968)]

Slightly off tangent, but hibernation (S4) fails in WinXP SP2 if you have more than 1GB of RAM. [microsoft.com]

Works just fine for me. Probably because I installed the udpate mentioned in the resolution section of the article sometime last year.

To see available Sleep modes from Windows Prompt

[icepick72 (834363)]

From command window:

powercfg -a
Works for both XP and Vista. Tells you what's available and what's not (S1, S2, S3,...) Vista tells you why something isn't support.

Got info from this page [tech-recipes.com]

Re:

[gEvil (beta) (945888)]

I haven't used any of the MacPro's, but in the PPC era the sleep state was similar to S3 standby.

Re:

[ettlz (639203)]

Back in the pre-NT-based days, perhaps. Most modern operating system kernels issue the HLT instruction plus some extra power management jiggery-pokery to the CPU when it's not being used at max anyway. (Check out /proc/acpi/processor/CPU*/power under Linux.)