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.

Comments

Laptops?

[Vo1t]

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

S3 and MCE

[gEvil (beta)]

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.

FreeBSD

[evilviper]

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]

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 /.

want a "file transfer" powerdown mode.

[plasmacutter]

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:want a "file transfer" powerdown mode.

[ivan256]

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 under 20 watts. This even works with dynamic content as long as you're not storing any data.

Re:want a "file transfer" powerdown mode.

[gbjbaanb]

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 drives up 1 at a time, rather than all at once - the simple reason being that the surge of power required to start them all up at once would trip the power protection circuitry.

Quick check on Google: an old 75Gb IBM deskstar drive takes 1.8amps at startup, 0.8 amps when used (0.6 amps when idle). Modern Seagate sata drives take 2.8amps at startup (but then settle down to 0.7amps active, 0.4 amps idle)

What about wireless ?

[Qwavel]

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?

Calculations are a bit off

[bogie]

"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: S3 Standby State Done Right

[AncientPC]

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

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. :(

Blame Bill Gates if it does not work.

[twitter]

Anyone who has not Bill Gate's memo about this should. Anything M$ touches is shit: winmodems, wifi, ACPI, APM and the list goes on and on. They can't make their own stuff work, so they have to break everyone else's.

Despite his efforts, power management can be made to work. It's not easy and you can't expect the latest and greatest to work. The closer a company's working relationship to M$ is, the harder it will be to make things work. For example, Dell is more difficult and Thinkpad is easier. As with most free software, if it's going to work the live distros will auto configure it and it will work almost out of the box.

I still use APM for the most part and have ignored conveniences like WoL.

sounds like a great way to wreck disks

[Loconut1389]

S3 standby shuts off hard drives and if you're running a file-server, aside from the lag people will experience between their packet and your computer reviving itself, power cycling your drives dozens of times a day will greatly reduce their lifespan. If you're worried about going green, buying an unnecessary hard drive probably puts more chemicals into the environment from its manufacturing than leaving your computer on?

Re:And Linux?

[flyingfsck]

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