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Measuring the User For CPU Frequency Scaling

timothy posted more than 5 years ago | from the no-this-one-goes-in-your-mouth dept.

Power 190

An anonymous reader writes "The Empathic Systems Project a Northwestern University demonstrate up to 50% power savings by controlling CPU frequency scaling based upon the end user. They measure the user with eye trackers, galvanic skin response, and force sensors to find a CPU frequency that the user is satisfied with. They are currently studying user activity and system performance on mobile architectures, specifically the Android G1 phone."

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first post (-1, Offtopic)

Reasoned Mind (1554009) | more than 5 years ago | (#27944599)

just registered... fp

Re:first post (0, Offtopic)

Anonymous Coward | more than 5 years ago | (#27944637)

Hey dumbass... I hope you realize that when this post gets modded down you will have negative karma.

It's almost impossible to recover from negative karma.

Time to register again...

Re:first post (-1, Flamebait)

Anonymous Coward | more than 5 years ago | (#27944685)

Hey dumbass, the point of a troll account is to troll with. You're the first one trolled. Congrats!

Re:first post (0)

Anonymous Coward | more than 5 years ago | (#27944751)

Let's make it a good one [slashdot.org] , shall we?

Re:first post (-1, Flamebait)

Anonymous Coward | more than 5 years ago | (#27944971)

Yeah... well let me know when you say something worthwhile instead of your stupid kike dreams.

I'll bet your bitch ass doesn't even know what trolling is. Hint: Just because you say you are trolling doesn't mean you are.

Sometimes you are just a punk bitch with negative karma and nothing of any value (trollig or otherwise) to say.

So try posting a real troll instead of your first post bullshit.

There is nothing sadder than a poseur troll...

By the way, my troll account has positive karma. Just another way that I'm better than you.

So does this mean (5, Funny)

MiKM (752717) | more than 5 years ago | (#27944621)

Does this mean that clicking a button multiple times and yelling at my computer will finally make my it go faster? Sweet!

Re:So does this mean (5, Funny)

plut4rch (1553209) | more than 5 years ago | (#27944695)

It's like a Turbo button but with your mind!

Re:So does this mean (1)

CarpetShark (865376) | more than 5 years ago | (#27945343)

It's like a Turbo button but with your mind!

So... your mind becomes a 486?

Re:So does this mean (4, Funny)

AHuxley (892839) | more than 5 years ago | (#27945835)

486 billion neurons should be enough for anybody.

Re:So does this mean (4, Insightful)

Anonymous Coward | more than 5 years ago | (#27944705)

No, it just means that not clicking a button multiple times and yelling will make it go slower.

Way I read it (5, Insightful)

Moraelin (679338) | more than 5 years ago | (#27944941)

Way I read it, it'll just make sure it goes just fast enough to want to make you scream for real anyway. I doubt that faking screaming alone will take care of the other variables they mention. But being genuinely stressed, probably will. And they'll underclock the computer until they start seeing what they consider an acceptable level of stress, regardless of whether you're actually screaming or not.

I seriously wonder who comes up with that kind of ideas. If the user seems to actually be enjoying his experience at the computer for a change, by all means, let's start degrading his/her experience until he starts showing some stress.

And it's good 'cause you can save a few watts! At the expense of probably reducing the user's life expectancy a little due to a constant baseline of stress, not just make him enjoy that life less. But it's teh green!

How much self-hate does someone need to actually want to punish themselves to save the planet? I guess we'll soon know.

Re:Way I read it (1)

Missing_dc (1074809) | more than 5 years ago | (#27944959)

Sounds like they are running "Windows"

Re:Way I read it (4, Funny)

popeye44 (929152) | more than 5 years ago | (#27945097)

Sounds to me like my porn avi's will start stuttering.. right to the magic moment.. then it'll clear up and play right.

Re:Way I read it (0, Flamebait)

john_roy (1538777) | more than 5 years ago | (#27945437)

How much self-hate does someone need to actually want to punish themselves to save the planet? I guess we'll soon know.

That's one of the most selfish comments I've seen in a while. It's because of people like you that we all live under shit, you selfish bastard.
What's a few watts, sure. Multiply that for the millions that use computers and you have your answer.

Re:Way I read it (1)

Runaway1956 (1322357) | more than 5 years ago | (#27945593)

Orly? Want to see real selfishness? Stand down at Walmart, and watch the fat bitches driving in with their huge SUV's. Skinny bitches too, I guess - but they are all to lazy to walk to a corner market for a gallon of milk. Nooo - we've just GOT to fire up that 300 - 500 hp engine, crank up the AC, and waste 2 or 3 gallons of gasoline to make that run to Walmart. What about the commuter crowd? Driving that gas hog as much as 100 miles each way, 5 days a week, because they are to damned good to live in the neighborhoods in which they work.

I'm with Moraelin - I want my computer to RUN!! If it doesn't, I might as well just push the damned bamboo shoots under my own fingernails. I'll tolerate a three minute boot-up (especially since I reboot very seldom) I'll tolerate a one minute login (again, I don't do it very often) and I'll tolerate (barely) my laggy internet connection. But, don't DARE try to throttle my damned machine down!!!!

If/when I feel the need to throttle it, I WILL DO SO, to suit my own personal goal.

Rent costs (3, Insightful)

tepples (727027) | more than 5 years ago | (#27945643)

What about the commuter crowd? Driving that gas hog as much as 100 miles each way, 5 days a week, because they are to damned good to live in the neighborhoods in which they work.

In a lot of cases, the commuter crowd lives this way because the gas is cheaper than rent near work.

Re:Rent costs (1)

Runaway1956 (1322357) | more than 5 years ago | (#27945843)

I'm sure that reason applies to some. In many cases, work is in an unattractive neighborhood, and the commuter has CHOSEN to buy/rent a home in a more "upscale" neighborhood. The last time I posted on the subject here at slashdot, some broad demonized me because she commutes like 35 or 40 miles. Her excuse? Her school age children deserve the best schools. Phhhht.

Re:Way I read it (0, Troll)

john_roy (1538777) | more than 5 years ago | (#27945783)

First of all, I can't stand down in to Wallmart and I don't have any intentions too because I'm not an American nor do I live in the US. You do know that SUV's is mostly an American thing. But that's not the point, and I'm not going to make this an country issue, since we have the same shit over here. I must point out that I only use my car on the weekend's and I do use public transportation, but I know that's not an option to everybody especially in the USA.
About your comment, It's the kind of thinking that don't make you any better. I don't do "this" because the others don't do "that"... I don't buy an hybrid car because I want to squeeze a few miles per hour of my car and my car as to be faster than my neighbor's car. I want my quad core 3 GHz always at full speed even that I don't use 5% of my 4 CPU's most of the time.
Good thinking both of you. You should be real proud...

Re:Way I read it (1)

Runaway1956 (1322357) | more than 5 years ago | (#27945907)

Don't worry - there will be a Walmart near you soon, along with one of those trashy McDonald's "restaurants". If not this year, then maybe next year, after some Euro or Chinese company buys Walmart out, and goes global.

Meanwhile - my 2.5 ghz machines will run full speed, 24/7. When I'm not actually USING them, they crunch Rosetta and Seti@home numbers.

Re:Way I read it (1)

john_roy (1538777) | more than 5 years ago | (#27946019)

Meanwhile - my 2.5 ghz machines will run full speed, 24/7. When I'm not actually USING them, they crunch Rosetta and Seti@home numbers.

Good for you. I see that you have are contributing to a greater cause. But I'm sure that even if you did run frequency scaling it wouldn't be any performance issue because as you probably well know frequency scaling identify when your CPU needs more than 5%.

I have a dual core 2.66 Desktop and my only regret is that the only allowed CPU freq are 2.00(75%) and 2.66(100%). If there was a 50% option on my CPU I will use it since I can't see the difference most of the time. When I'm compiling or playing Quake4 the CPU goes 100%. The only difference I've noticed is in the electric bill at the end of the month.

Re:Way I read it (2, Insightful)

SanityInAnarchy (655584) | more than 5 years ago | (#27946119)

Point is, we really shouldn't have to make this choice.

Electricity is just electricity. It can come from coal or oil, yes. It can also come from a waterfall, or a nuclear reaction, or the wind, or the sun, even geothermal...

Saving a few watts, multiplied by thousands of people, still isn't going to make a tiny fraction of the difference of, say, replacing a coal plant with a wind farm.

No, I'm guessing they're mainly focusing on battery life for mobile apps. And I applaud them for that, but I don't know that I like this particular method. I'd rather have it jump right up to full throttle when I need it, without me having to get stressed. And I'd much rather see effort put towards better batteries, and generating electricity from other sources -- like movement, considering how much I might be walking around with a mobile device...

Re:Way I read it (1)

PitaBred (632671) | more than 5 years ago | (#27945601)

Depends entirely on what the "acceptable level of stress" is set at. There are very few times where a person will need a machine running flat-out all the time. Hell, I barely even notice that I have frequency scaling turned on on my laptop (it's undervolted too... lasts much longer on battery). And that's not even taking into account my mood.

Give these researchers a little credit... they use the devices, too.

Re:Way I read it (4, Informative)

hazem (472289) | more than 5 years ago | (#27945677)

How much self-hate does someone need to actually want to punish themselves to save the planet? I guess we'll soon know.

I don't think it's self-hate that drives this thinking. Rather it's a desire to be aware of how one's day to day decisions have a broader impact on the planet as a whole - and choosing to limit that impact where possible.

The 19th and 20th centuries and the growth of industrialism and consumerism was based on the idea that resources are infinite and pollution negligible. Under those "constraints", there is no reason to constrain yourself - do what you want because there are not consequences. Sadly for us, those assumptions are not accurate. The resources are indeed finite, and the cumulative effect of the pollutants we produce are now measurable.

It IS indeed painful to shift from a "I can have and do whatever I want" mindset to one where you think about the impact of everything you do. The real problem is that it's impossible to track the impact of the behaviors of one person on the global system. _I_ can pee in the well and we all still have pretty safe drinking water. But if we all individually make that same choice, we all pretty soon have bad water.

As for this system, it sounds horrible and would most likely be abused in the worst way. The idea in one perspective sounds good... identify where resources are needed and increase them. But what you describe is more likely, particularly from a capitalist mindset - continue degrading the experience until it is just barely acceptable.

What makes much more sense is to make a little widget that can show how much energy is being used in a given state and let the user decide how much they might want to slow down the processor. If they care about saving energy, they can dial it down themselves to the level they can tolerate. If they want a faster experience (vital in number crunching and gaming), let them do that - and the widget can show the incremental cost.

In a similar way of thinking, they just installed a new "smart" electric meter on my house. I really hope I'm able to access the data from it. If I can get variable pricing based on peak load in the system, then I have a lot of incentive to time my dish washer, clothes washer, etc to do their work in the non-peak times. It saves me money and makes a more efficient load on the system. Everyone wins. Hopefully they don't screw it up.

Re:Way I read it (1)

Spyder0101 (1485837) | more than 5 years ago | (#27946023)

Assuming accurate enough readings, your complaint is a non-issue. Even without any readings, a very fine-tuned control that allows you to throttle it yourself would be great. This is not for use on a desktop, this is for mobile devices. What is more stressful; waiting an extra second while an app boots and being mildly annoyed before the device throttles up to finish a bit quicker or your battery dying in the middle of an important phone call? I know I'll waste a second for up to 50% more battery life.

Re:So does this mean (3, Funny)

mrsquid0 (1335303) | more than 5 years ago | (#27945295)

What I really want is for a download to speed up when I drag the progress bar.

Remember, this is on the Android G1 phone ... (1)

gun26 (151620) | more than 5 years ago | (#27945665)

... so, presumably, this isn't really about improving the speed but is instead a desperate attempt to get an actual full day's use out of the G1 before it has to be recharged. Reach for those stars, boys. :)

Re:So does this mean (1)

martin-boundary (547041) | more than 5 years ago | (#27946127)

Does this mean that clicking a button multiple times and yelling at my computer will finally make my it go faster?

Or maybe the opposite. Think "a watched pot never boils". They'll call it CPUPersonality(TM).

And of course... (1)

Chabo (880571) | more than 5 years ago | (#27944645)

Wide, crazy eyes and frantic button mashing mean that the CPU should be overclocked as much as possible, while closed eyes mean that the system should ignore changing the CPU frequency, and send a System Beep straight through the headphones.

Re:And of course... (0)

Anonymous Coward | more than 5 years ago | (#27944949)

In related news, a system beep when eyes remain closed for longer than 30 seconds has been shown to cause a 50% savings in monetary spending.

The theory is that gamers can be woken up by their PC, so they need less energy drinks to function.

Careful Limitiations (0)

Anonymous Coward | more than 5 years ago | (#27944677)

I have to say, I have to be worried if there aren't caps based upon the chip in use.

If we're really wanting things to go faster will this push it too hard and overclock the system?
If we're really lethargic about it will it underclock the system too much? I don't know if running a chip too slow can damage it but I think there may be consequences besides battery life.

Re:Careful Limitiations (1)

Ethanol-fueled (1125189) | more than 5 years ago | (#27945045)

I doubt that they'd allow the "fastest" settings to run overspec with regards to the system. Keep in mind that TFA was basically about research done for research's own sake. It'd be much easier to let the user define which threshold is more comfortable for them with a "faster/slower" slider or use existing speedstepping technology without the overhead of gesture-sensing.

"We saw there were instances where scaling back the central processing unit frequency didn't affect the user satisfaction, but it saved power," Shye says.

That ties in to the fact that much of our modern technology is so fast that it can do anything we want with power to spare, and why not conserve that power for longer battery life? Would the overhead make it more feasible than existing throttling technologies? Like I said, research for research's own sake.

Re:Careful Limitiations (2, Insightful)

cskrat (921721) | more than 5 years ago | (#27945109)

Nobody said anything about overclocking. And yes, underclocking does have limits imposed by the system's processor and BIOS. AMD and Intel already have features on all their product lines to allow for dynamic clock adjustments to reduce power consumption. AMD's cool and quiet feature will even lower the CPU voltage at lower clock frequencies to further reduce power consumption.

These guys aren't talking about new processor designs (though I'm sure some engineers at AMD and Intel read /. and will find this research), they're looking for ways to better implement the power saving features that are already present in modern CPUs.

Re:Careful Limitiations (1)

John Hasler (414242) | more than 5 years ago | (#27945977)

> These guys aren't talking about new processor designs (though I'm sure some engineers at
> AMD and Intel read /. and will find this research), they're looking for ways to better
> implement the power saving features that are already present in modern CPUs.

They also seem to be assuming that the only function of the cpu is to provide snappy GUI response (which is probably true for most users).

Overhead? (5, Insightful)

bcmm (768152) | more than 5 years ago | (#27944679)

I cannot imagine that, in the near future, a mobile device will draw more power by just using full processor speed than it would by having to power all those sensors and interpret their data.

Re:Overhead? (1)

Red Flayer (890720) | more than 5 years ago | (#27944729)

I cannot imagine that, in the near future, a mobile device will draw more power by just using full processor speed than it would by having to power all those sensors and interpret their data.

It's good that you cannot imagine that. Because if you could imagine that, then it might be something to be worried about.

As an aside, interpreting the data would likely be done by the processor, so if you're going to be running the processor at full speed, then the only thing to be concerned about is the draw of the sensors.

Re:Overhead? (4, Interesting)

tkw954 (709413) | more than 5 years ago | (#27945741)

I recently did a test on a fanless VIA Eden system (CPU + mobo + RAM + notebook hd + 2 Delta 1010LT soundcards with a switch mode PSU). The power consumption was 29.1 W with the system idling and throttled down (600 MHz) and 31.9 W with a full 'ping -f localhost' load (1200 MHz). I know it's not an embedded ARM system, but this does give an idea of the nearly negligible power savings available by halving your clock speed.

so what this means is? (1)

FudRucker (866063) | more than 5 years ago | (#27944691)

most people would be happy with something like win9x or win2k (linux for me thanks) on a 750Mhz CPU and 512 megs ram?

Re:so what this means is? (4, Informative)

Moryath (553296) | more than 5 years ago | (#27944727)

Most of the drain users see today is OS bloat and Virus scan software bloat. Face it, A "fully updated" WinXP SP3 with a fully updated, modern antivirus package needs ~4 times the hardware a base WinXP (or even Win2K SP4) system would want.

Re:so what this means is? (2, Insightful)

silas_moeckel (234313) | more than 5 years ago | (#27944805)

This is simple all OS/App developers need to be given a 3 year old PC to test on. They need the big honking system to code/compile on.

Re:so what this means is? (1, Interesting)

Darkness404 (1287218) | more than 5 years ago | (#27945129)

3 year old? I'm sorry but I expect all programs that aren't games (and some CPU intensive programs) to run perfectly well on an early P4 with 512 MB of RAM. I currently use a 4-5 year old computer for most day-to-day work.

All programs/OSes should work perfectly on hardware made in ~2003, many people still have these (or older) computers, especially if they live outside of high speed internet access, or aren't very computer literate.

Re:so what this means is? (1)

DMalic (1118167) | more than 5 years ago | (#27945749)

What!? I'd agree with you if not for the little subject of Intel's worthless POS integrated chips - the ones 1/3 as powerful as everyone else's integrated graphics. I like seeing desktop compositing and media decoding passed off to my GPU, thankyou very much =)

That's actually just the start (4, Insightful)

Moraelin (679338) | more than 5 years ago | (#27945103)

Actually, I'd say that's just the start of the problems. The next problem will be that half of anything you install nowadays, will want to preload itself or parts of itself in your tray, or install some services, or God knows what else.

And I'm not even talking proper spyware. E.g., even when I install OOo, the first thing I have to do is deactivate its preloading itself. 'Cause obviously they thought my RAM is there just so they can willy-wave about loading faster than MS Office, instead of fixing their brain-dead code to actually be fast. (Though apparently in the last release they actually did get around to optimizing a bit for a change.)

E.g., I install Sun's Java, 'course, it has to keep something in the tray just to make sure it can pester me to download the latest release I don't even want.

E.g., I install my old Audigy 4's software after moving it to another computer, and I promptly remember what I hated about its software in the first place. By default it installs a brain-dead bloated skinned second toolbar, so to speak, just in case I'm too stupid to launch its control pannels normally. And so it can get in my way when I accidentally move the mouse to its edge. It also installs stuff like its own CD/DVD detector (and launcher of the apropriate program for it), for no obvious reason, since Windows already does a perfectly good job there. It also blesses my computer with a bloated, slow loading splash screen, 'cause obviously doubling my computer's startup time is perfectly ok if it lets them shove in my face again that it runs an Audigy. Obviously my time and RAM are there just so they can advertise to me. Etc.

I'm not even singling out OOo or Java there, mind you. Lots of others do the same.

And then come the games, with their retarded DRM drivers and whatnot.

My point is that it used to be a time when you actually had to get virused or click on spyware to get half a gigabyte of your RAM full with crap. Increasingly in the last decade, you don't even need to do that. Just installing perfectly legit software can make your computer swap, if you're not savvy enough to find that crap in the registry and disable its auto-loading. Sometimes twice, because some are smart enough to re-enable themselves.

Re:That's actually just the start (0)

Anonymous Coward | more than 5 years ago | (#27945307)

Don't worry, it's as bad in linux now. Install a modern distro and even after you swap over to a lightweight desktop you'll have hald, dbus, pulse audio, gnome-settings-daemon, gnome-keyring and a few other pieces of shit conspiring to turn what should be a perfectly usable desktop machine to the equivalent of running a in VM on the same hardware 18 months ago.

Re:That's actually just the start (0)

Anonymous Coward | more than 5 years ago | (#27945415)

Start-Run-msconfig-chose "Selective startup"-go to the startup tab, uncheck all unnecessary.
Sheesh.

Re:That's actually just the start (2, Informative)

ShooterNeo (555040) | more than 5 years ago | (#27945539)

That doesn't actually kill anything that runs as a system service... Also, some programs will re-add themselves to that menu.

Re:That's actually just the start (1)

Voyager529 (1363959) | more than 5 years ago | (#27945599)

Rant Warning

The worse offender I've ever come across was when LG and Samsung included tray-resident apps...FOR FIRMWARE UPDATES! There is something seriously wrong with your drive if you need to have it constantly checking for new firmware, only eclipsed by the retarted thinking that people will be able to flash the firmware in the drive and NOT brick it.

Okay, I'm done with my rant. I wholeheartedly agree though, it seems that software devs have confused the system tray with the start menu. No need for 90% of the stuff that starts with computers to start with the computer by default.

Re:That's actually just the start (1)

TJamieson (218336) | more than 5 years ago | (#27945991)

By default it installs a brain-dead bloated skinned second toolbar, so to speak, just in case I'm too stupid to launch its control pannels normally. And so it can get in my way when I accidentally move the mouse to its edge.

They still have that shit in their software? I remember being annoyed by that 10 years ago with my SBLive.

Re:so what this means is? (1)

Red Flayer (890720) | more than 5 years ago | (#27945173)

Face it, A "fully updated" WinXP SP3 with a fully updated, modern antivirus package needs ~4 times the hardware a base WinXP (or even Win2K SP4) system would want.

That's nonsense. A base WinXP system (instead of a fully update XPSP3 + AV) would max out the processor and the internet bandwidth within days, if not hours, of being turned on.

See, what happens is that friendly hackers automagically scan the ports of a base XP install, then kindly install their own "service packs" to help make sure the XP system is using all its available resources. You woyludn't want to waste your resources, right?

Re:so what this means is? (1)

tagno25 (1518033) | more than 5 years ago | (#27945299)

That's nonsense. A base WinXP system (instead of a fully update XPSP3 + AV) would max out the processor and the internet bandwidth within days, if not hours, of being turned on.

No, that is nonsense. If you are dumb enough to put any insecure OS directly onto the IPv4 (IPv6 is too large for hacking random IPs) internet then you deserve anything and every thing you get.

Re:so what this means is? (1)

DMalic (1118167) | more than 5 years ago | (#27945729)

I'm not sure it's "OS Bloat". With indexing turned off and no A/V I get 0% CPU use. I can't imagine Antivirus would up that all that much more. I think it's mostly little application bloat - quicktime and java and flash and the 182492814 other things you have to install sludge it up over time. A new installation IS so much faster than an old, heavily used one - even if both have msconfig startup lists cleaned out.

Re:so what this means is? (0)

Anonymous Coward | more than 5 years ago | (#27944865)

No, CPU isn't the bottleneck, never really has been. RAM and pathetic hard-drive IO is the problem for the vast majority of users. RAM is cheap now and no longer an issue. HDs have a long way to go for acceptable speed. Maybe when SSD drives have something resembling real world capacity, our machines will begin to feel less suggish.

First Step (2, Funny)

ThistleForce (1554011) | more than 5 years ago | (#27944715)

Computers changing performance based on our moods? Hmm...i'm thinking android girlfriends are closer than we realize! It would be interesting to see just how much battery power this would save on my rig?

Re:First Step (1)

macraig (621737) | more than 5 years ago | (#27945095)

Don't forget that these extra circuits and sensors will use power themselves, so the savings will be a bit less than you might hope. Also don't forget that this new bling will drive up the cost of NYM (Next Year's Model), so you'll be saving some money in one bookkeeping column by spending it in another....

Sounds way too complicated (0)

Anonymous Coward | more than 5 years ago | (#27944733)

I suspect users do not care if things are fast enough. So you want the cpu to run just fast enough that you are not waiting on the CPU. And you should be able to tell that without all that galvanic, eye-tracking nonsense.

I suspect any waiting that might actually annoy the user to the point these complicated sensors might read is not going to be fixed by the CPU speed.

Re:Sounds way too complicated (1)

exploder (196936) | more than 5 years ago | (#27944899)

Plus, what if I'm a fairly laid-back guy who doesn't bust a vein when my phone is sluggish? Will it just get slower, trying in vain to piss me off? That sounds _awesome_.

Right out of Craig's List Adult Section . . . (1)

PolygamousRanchKid (1290638) | more than 5 years ago | (#27944759)

They measure the user with eye trackers, galvanic skin response, and force sensors to find a CPU frequency that the user is satisfied with.

Um, . . . yeah . . . okay . . .

"The Empathic Systems Project"

Oh, what a giveaway . . . "I'd like to buy some empathy . . ."

This just in, breaking news (1)

Hadlock (143607) | more than 5 years ago | (#27944761)

Corporate customers found a 60% power consumption decrease after they found that most users are happy with scaling their computer back to 333mhz once microsoft office is fully loaded. Customers reported that most power consumption occurred during employee recreational time at work, when Youtube and Flash games take up the majority of the user's cycles.

Waste of Time (2, Insightful)

sexconker (1179573) | more than 5 years ago | (#27944789)

So if I walk away from my machine to let it process a job, it'll go slower?

If this is to save power, then reducing speed when an intensive task is performed is retarded, since you'll waste energy (having to run the task proportionately longer).

If we're only taking into account saving power when idle/mostly idle, then basing this off of metrics from the user is a waste of effort. Just test your apps and see what a user feels is "fast" for certain tasks, then attach those target times to those tasks, and let the CPU try to hit that target.

You'll waste less energy monitoring a user's behavior and galvanic boner response, and you won't annoy the user when your system behaves inconsistently.

If you want, you can let users specify whether or not they want to emphasize battery life or performance, or turn the feature off entirely and let shit work as it should.

The trick would be getting this shit implemented at level low enough that each app would be able to specify target times and specific tasks. Of course, if you're the fuckers worried about battery life, you're the one designing the hardware/platform, so you've got control.

Re:Waste of Time (4, Interesting)

tlhIngan (30335) | more than 5 years ago | (#27944991)

So if I walk away from my machine to let it process a job, it'll go slower?

If this is to save power, then reducing speed when an intensive task is performed is retarded, since you'll waste energy (having to run the task proportionately longer).

If we're only taking into account saving power when idle/mostly idle, then basing this off of metrics from the user is a waste of effort. Just test your apps and see what a user feels is "fast" for certain tasks, then attach those target times to those tasks, and let the CPU try to hit that target.

You'll waste less energy monitoring a user's behavior and galvanic boner response, and you won't annoy the user when your system behaves inconsistently.

If you want, you can let users specify whether or not they want to emphasize battery life or performance, or turn the feature off entirely and let shit work as it should.

The trick would be getting this shit implemented at level low enough that each app would be able to specify target times and specific tasks. Of course, if you're the fuckers worried about battery life, you're the one designing the hardware/platform, so you've got control.

Except, this technology is NOT for computing applications, but for mobile applications - e.g., a phone.

For a phone, you do not want background processing tasks - they force the processor to stay "awake" and drain the battery very quickly. Even a simple task that wakes the CPU up every second will easily cause battery life to diminish from the 2+ weeks standby to a few days. (Take your battery capacity and divide it by the standby time - you'll find you have around 2-3mA to play with, which is just enough to maintain the radio connectivity).

Mobile processors have a technique known as DVFS - dynamic voltage and frequency scaling. The goal is to keep the voltage as low as possible (power consumed is proportional to voltage squared), which may mean you run the CPU at a lower frequency. There's a bit of overhead in switching frequencies, including having to ramp up core voltages and adjusting clocks, waiting for them to stabilize, etc.

The trick though, is to realize when the user really doesn't care for speed, and thus keep the CPU in a lower frequency (e.g., playing music), versus the user is actively doing stuff, and it would be desirable to have it finish as fast as possible (e.g., browsing the web) so while the user ponders, you can put the CPU into a low power state immediately, versus keep it at a slow clock and have the user wait. Also, you have to figure out when the user is doing something that really is requiring a lot of CPU power (playing movies), so you have to bump the speed up and hold it there, and not at the first instance of idleness, drop back down.

Basically, having this feedback ltes you find out what is going on - is the user not caring, and thus you should pick the slowest speed that'll get things done? Is the user actively engaged in the device, but the usage is bursty, so you should go into a low power state after the processing is done, or is the user doing something that requires processor, and dropping down wastes power due to overhead?

Re:Waste of Time (1)

sexconker (1179573) | more than 5 years ago | (#27945301)

For a phone, I do not want something trying to measure my eye movements, my skin, etc.

I want the shit to be as fast as possible so i can be done as soon as possible and the thing can be back in my pocket with the screen off, the speaker off, the bluetooth off, and the radio in it's lowest-power mode.

Throttling back speed means you have to run for longer to get anything done.
You can't throttle back power hogs like the screen or the radio, either.

This is a lot of noise about what will amount to something less effective than what we already have - throttling back when idle/near idle.

Re:Waste of Time (3, Insightful)

Chris Burke (6130) | more than 5 years ago | (#27946067)

The trick though, is to realize when the user really doesn't care for speed, and thus keep the CPU in a lower frequency (e.g., playing music), versus the user is actively doing stuff, and it would be desirable to have it finish as fast as possible (e.g., browsing the web) so while the user ponders, you can put the CPU into a low power state immediately, versus keep it at a slow clock and have the user wait. Also, you have to figure out when the user is doing something that really is requiring a lot of CPU power (playing movies), so you have to bump the speed up and hold it there, and not at the first instance of idleness, drop back down.

Basically, having this feedback ltes you find out what is going on - is the user not caring, and thus you should pick the slowest speed that'll get things done? Is the user actively engaged in the device, but the usage is bursty, so you should go into a low power state after the processing is done, or is the user doing something that requires processor, and dropping down wastes power due to overhead?

Everything you say is true, but it makes vastly more sense to determine the amount of processor speed needed by what the device is actually being asked to do rather than trying to glean the user's mood and how that relates to required processor speed. Decoding an mp3 is a low intensity activity, and you don't need to know the user's heart rate or any nonsense like that to know you can afford to turn down the cpu frequency if that's all its being asked to do. Similarly, no matter how emotional the user is getting over the text message they are typing, the processor is still going to be sitting in its idle loop 99% of the time waiting for the next keypress so it's perfectly safe to lower the frequency there too. If they're doing something that requires a lot more processor, well, again this is obvious from the processor's point of view. And while the switches themselves are slow from the processor's point of view, they are too fast to notice from the user's point of view so it's perfectly feasible to switch from one to the other as processor load indicates.

So given that we already know how* to tune a processor's frequency to match the work being asked of it in a way that minimizes power consumption but never appears "slow" to the user, what exactly does this add? Is it for when someone starts playing a CPU intensive game on their iPhone, but isn't actually playing it? Yeah I'm sure you could save a lot of power by realizing that the user isn't in the same room as the device, so their Quake framerate really dosen't matter. So would an auto-shutoff after two minutes of no user input, and my phone already has that too.

* It's not like there's some proven ideal algorithm for it, but nevertheless existing devices do a pretty good job and are getting better.

Is this dymanic? (1)

davidwr (791652) | more than 5 years ago | (#27944793)

When I'm reading the news, the computer can freeze and I won't notice unless some animated ad freezes, in which case I'll be grateful.

But as soon as I wiggle the mouse or the clock is due to change, screen better respond.

If I'm playing WoW or watching a DVD, my CPU and GPU and the rest of the system better be operating fast enough to keep up.

Hmm... (4, Insightful)

fuzzyfuzzyfungus (1223518) | more than 5 years ago | (#27944817)

Any word on how this compares to the current recieved wisdom of "when you have a job, do it as fast as possible, then go to sleep"?

I don't want to be "that guy on the internet who says it can't possibly work from the comfort of his armchair"; and I'm all for new and interesting sensor integration schemes; but this strikes me as the sort of problem that is already mostly solved with far simpler techniques.

We can already rank processes by priority, via nice or similar, and we already know a decent amount about user psychology(people hate waiting and find unresponsive interfaces enormously frustrating), and determining "what combination of speed states across time will execute this sequence of instructions with the lowest energy cost, subject to the desireability of having the results sooner rather than later?" is a solvable problem.

Can we really learn individual quirks, not covered by general rules, or is this basically a system that underclocks your phone until just before the point where your head explodes?

Re:Hmm... (1)

Actually, I do RTFA (1058596) | more than 5 years ago | (#27945877)

determining "what combination of speed states across time will execute this sequence of instructions with the lowest energy cost, subject to the desireability of having the results sooner rather than later?" is a solvable problem.

That assumes we want the results sooner rather than later. For most phone apps, this isn't the case. So you can get extra power savings if you know when you want the results. Which they guess by how annoyed the user is.

Repurpose the SysRq key (1)

Mal-2 (675116) | more than 5 years ago | (#27944947)

What good is the SysRq key? Repurpose it as a way for the user to say "please assign more system resources to whatever is in the foreground". If this can be done by clocking up, great. If the CPU is maxed out, then bump up the priority of the process. If there's nothing left to give, then the system beeps or throws a "tough shit, you bought the $100 computer" dialog box.

It does not seem like fundamentally new technology is necessary for us to be able to tell the computer it's lagging unacceptably. That doesn't necessarily mean it will be able to DO anything about it, but at least we can vent.

Mal-2

Re:Repurpose the SysRq key (0)

Anonymous Coward | more than 5 years ago | (#27945019)

"tough shit, you bought the $100 computer" dialog box.

Even a half million dollar Cray would bow down to a Vista system running Crysis.

Re:Repurpose the SysRq key (1)

tagno25 (1518033) | more than 5 years ago | (#27945073)

What good is the SysRq key?

It is very helpful when you have a kernel panic. It lets you safely unmount and reboot the system.
On another note the Windows kernel panic (not BSOD) in Vista looks and behaves just like it does in Linux.

Re:Repurpose the SysRq key (1)

cibyr (898667) | more than 5 years ago | (#27945077)

I use that key still... how do you take screenshots?

And Alt+SysReq+{R,E,I,S,U,B} can safely reboot a locked-up linux system if the "Magic SysReq Key" kernel option is enabled.

Re:Repurpose the SysRq key (1)

Mal-2 (675116) | more than 5 years ago | (#27945197)

Ctrl-PrtSc or Alt-PrtSc depending on whether I want the entire desktop or just the single application. I don't use SysRq *alone*.

Mal-2

Re:Repurpose the SysRq key (1)

Sir_Lewk (967686) | more than 5 years ago | (#27945231)

how do you take screenshots?

PtrSc, on the same physical button as my SysRq key.

Not really needed (1)

Sycraft-fu (314770) | more than 5 years ago | (#27945771)

A modern desktop (Windows desktop at any rate, presumably other OSes too) already does a lot of this. By default foreground threads get priority so you'll find that the foreground app gets to gobble up lots of CPU time if it wishes.

As for the clocking up, that is a hardware function that modern processors support well. My Core 2 Quad idles at about 2Ghz, which translates to a 6x multiplier. That's what it'll be running with system tasks going and a web browser and other such non-intense stuff. Now if I fire up something that hits the CPU, it clocks up to an 8.5 multiplier, which is 2.83GHz, it's rated speed. My graphics card does a similar thing, though with even larger clock deltas.

So we don't even need a key for users to press. All we need is further improvements to the existing technology. For example my processor could probably scale its speed even further. It also could potentially shut down ancillary cores. Though I have a couple hundred threads running on an idle system, most are doing little thus it could easily shut down two cores, clock the remaining two down, maybe one of them way down. So long as the time to restart the other cores and clock up was fast, it wouldn't be a performance or responsiveness problem.

We already have the technology we need, and it already works well. We just need to continue to improve it.

Correct CPU frequency (3, Funny)

Capt.DrumkenBum (1173011) | more than 5 years ago | (#27944967)

What a useless study. I can tell you what system I need.
The correct CPU and frequency is currently a 100GHz 16 Core beast with 4TB of RAM. Of course I will NEED a machine that is twice as fast in 18 months.

Re:Correct CPU frequency (1)

Voyager529 (1363959) | more than 5 years ago | (#27945637)

But can it run Vista?

Waste of effort for negative gain (0)

Anonymous Coward | more than 5 years ago | (#27944983)

This is a huge waste. It's much more efficient to get the processing done as fast as possible and then put the CPU to sleep until there is more work to do. If you slow everything down, the CPU is working longer which takes more power.

Software based (1)

tagno25 (1518033) | more than 5 years ago | (#27944985)

Why not just do like Linux can and does, have 4 settings that control how the processor functions.

I have the option between Conservative, Ondemand(Increases when processor usage is needed), Preformance(always at max), and Powersave(always at min). When my laptop is unplugged then it runs in powersave mode, but when plugged in then it is in ondemand mode.

Re:Software based (1)

retchdog (1319261) | more than 5 years ago | (#27945179)

1. Windows works almost exactly the same way, except with a moronic additional "degrade" option which is usually disabled nowadays.

2. If you have occasional spikes of demand (as opposed to continuously running job/game), "powersave" probably uses more power. It's more efficient to spike the proc to max for a few seconds; finish the job; and go back to mostly-idle.

Or in other words... (1)

macraig (621737) | more than 5 years ago | (#27945017)

... using a mood ring to control the CPU? The hippies will love it!

I wonder... (1, Funny)

Anonymous Coward | more than 5 years ago | (#27945027)

...what CPU frequency they'd give this kid

http://www.youtube.com/watch?v=kBVmfIUR1DA

scientology's tech stolen! (1)

TomR teh Pirate (1554037) | more than 5 years ago | (#27945029)

This is the same technology the guy working the Scientology booth at the local mall uses when he asks you some questions that are none of his business. Of course you're squeezing it harder; you can't wait to tell the guy he's an idiot.

Re:scientology's tech stolen! (1)

pxc (938367) | more than 5 years ago | (#27945881)

Actually, those things measure electrical resistance and display it with the leftmost part of the gauge representing resistance greater than current, and the right side representing no resistance.

The last time I was downtown, I decided to test this as I walked by a Scientology booth. During my "free stress test", I touched the two cans together, and the needle jumped all the way to the right.

Spam... (0)

Anonymous Coward | more than 5 years ago | (#27945031)

This paper was cute and pointless the first time I read it. Congrats on being the least technical paper in MICRO last year, now stop spamming your research to Slashdot.

Excellent (1)

kramulous (977841) | more than 5 years ago | (#27945033)

Good that there is thought to this.

Kinda like tuning your codes to run really fast, then the poor monkeys in the basement send you a IR photo of some power couplings and ask what you're doing. I've always been going for flops but it has been getting a little more difficult now that I bring in power consumption into the optimisation cycle.

New measurement for the top500
flopspw ?

Re:Excellent (1)

kramulous (977841) | more than 5 years ago | (#27945067)

Sorry, that new performance measurement should be
flopspa

Re:Excellent (3, Insightful)

jpmorgan (517966) | more than 5 years ago | (#27945147)

You might be surprised, but a lot of commercial HPC sales are already based on flops/watt.

Lots of companies make extensive use of computational models these days, but have offices in older buildings that don't have sufficient power infrastructure. When your power supply maxes out at 50kW, flops/watt becomes more important than straight flops.

Re:Excellent (1)

Jherek Carnelian (831679) | more than 5 years ago | (#27946015)

New measurement for the top500

It's called the Green500 [green500.org] list.

Seems rather retarded (1)

Sycraft-fu (314770) | more than 5 years ago | (#27945071)

I always want my computer to complete any task that I have to wait on as fast as possible. I don't like waiting if I don't have to. Thus, all necessary power should be thrown at a given task. The time to scale back, is when it is waiting on me. If I'm not giving it something to do, it can throttle back and idle.

However, we already have this technology. New processors and even videocards now do this. That is the technology that needs improvement. Have lots of power available, and only crank it up when there is a need. The idea being that the user never has to wait on anything, but the computer uses only the power necessary to complete the given task.

I don't want my computer sandbagging and only going half speed because it thinks that's "Good enough for me." No, go the speed the task you are doing demands (or full speed if said task needs more power than the system has).

Re:Seems rather retarded (1)

camperdave (969942) | more than 5 years ago | (#27945333)

I don't like waiting if I don't have to.

Perhaps you'd like a tee shirt [cafepress.com] .

Blackberry Storm (0)

Anonymous Coward | more than 5 years ago | (#27945131)

Does it automatically overclock the Blackberry Storm so that it shows some semblance of responsiveness?

Another idea (0)

Anonymous Coward | more than 5 years ago | (#27945235)

Or, instead of slowing down the system until the user is annoyed, you could just give them a slider bar somewhere to decide between "Fast" and "Low Power Usage." That way you're not stealing control from them and hacking them off.

Just No (1)

jvkjvk (102057) | more than 5 years ago | (#27945337)

I want my computing experience to be pleasant, not have the power turned down until I am stressed at how slowly things are going and then have it ramped up again.

Sorry, but I have enough stress as it is without artificially adding more.

It's like we are becoming monkeys jumping through flaming hoops just to satisfy the computer! Bah.

For the system's icon... (0)

Anonymous Coward | more than 5 years ago | (#27945341)

A Talosian's head appears: "Wrong thinking is punishable. Right thinking will be as quickly rewarded."

This will be fun... (2, Insightful)

rickb928 (945187) | more than 5 years ago | (#27945389)

They measure the user with eye trackers, galvanic skin response, and force sensors to find a CPU frequency that the user is satisfied with. They are currently studying user activity and system performance on mobile architectures, specifically the Android G1 phone."

Yeah, so that's why my G1 keeps asking me to turn it over, so the camera can track my eyes. Perhaps they should try tracking the acclerometers so they see them max out when the battery goes dead and I heave it one more time into the trash, only to pick it out again and recharge. Yeah, that's sure scientific. Good work there.

Or maybe they are working with the other Android phone on the market that has a user-facing camera.

For a phone, you do not want background processing tasks - they force the processor to stay "awake" and drain the battery very quickly

Yup. Stop calling my G1 a phone. It's a handheld. Phones have reasonable battery life. There. Carry on.

Another great stride for AI (1, Funny)

Anonymous Coward | more than 5 years ago | (#27945435)

They have invented a computer that goofs off whenever you are not looking.

Strange... some would say I do this at work... (1)

Solarbeat (691941) | more than 5 years ago | (#27945465)

In the words of the immortal Homer Simpson: "You just go in there every day, and do it really half-assed... that's the American way!" My wife would probably say that I do this at home too (I just opened myself up for all sorts of insults there).

How about a shock sensor (2, Funny)

billcopc (196330) | more than 5 years ago | (#27945645)

I'd like a computer that speeds up, every time I smash the keyboard or mouse in anger, you know, like a human would...

That should be easier to implement than my previous suggestion, which was a speech recognition algo that interprets swearing in various languages and can tell the difference in intensity between "Ah crap" and "STUPID F&@#IN' GODDAMNED TABARNAK MOTHERF&*@&#$ OUTLOOK!".

Morons (1)

oldhack (1037484) | more than 5 years ago | (#27945661)

Time to burn some karma points.

Tell me one advantage this knucklehead idea possesses over having a simple slider/dial to adjust processor speed.

Re:Morons (1)

John Hasler (414242) | more than 5 years ago | (#27945999)

> Tell me one advantage this knucklehead idea possesses over having a simple slider/dial
> to adjust processor speed.

It is suitable for knuckleheads who couldn't deal with such a slider.

fir5t pNost (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#27945705)

argued by Eric lat$er ssen in

farts (0, Troll)

NicknamesAreStupid (1040118) | more than 5 years ago | (#27946021)

Why don't we just plug them into out butts and run 'em on methane. Mine would clock 10THz.
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