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Power Input Devices Portables Hardware Technology

Measuring the User For CPU Frequency Scaling 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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Measuring the User For CPU Frequency Scaling

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  • by MiKM ( 752717 ) on Wednesday May 13, 2009 @04:52PM (#27944621)
    Does this mean that clicking a button multiple times and yelling at my computer will finally make my it go faster? Sweet!
    • by plut4rch ( 1553209 ) on Wednesday May 13, 2009 @04:57PM (#27944695)
      It's like a Turbo button but with your mind!
    • by Anonymous Coward on Wednesday May 13, 2009 @04:58PM (#27944705)

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

    • Way I read it (Score:5, Insightful)

      by Moraelin ( 679338 ) on Wednesday May 13, 2009 @05:17PM (#27944941) Journal

      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.

      • Sounds like they are running "Windows"

      • by popeye44 ( 929152 ) on Wednesday May 13, 2009 @05:34PM (#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.
      • 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 (Score:5, Informative)

        by hazem ( 472289 ) on Wednesday May 13, 2009 @06:33PM (#27945677) Journal

        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.

        • by adolf ( 21054 )

          But to add stress in order to shave a few Watts?

          I'm all for cleaning up the mess we've made of things, but not if it makes my personal environment less tolerable by design.

          I'm not masochistic enough for this technology.

        • by GigsVT ( 208848 )

          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.

          http://www.theenergydetective.com/store/teds/ted1000.html [theenergydetective.com]

          You can get this for not much money.

        • Re: (Score:2, Insightful)

          by batman567 ( 1554289 )
          i'd rather have my CPU running at 100%, than to have it running at 70%, and the other 30% being used to monitor my eyes, skin and nervous state of being!!! as for saving the planet - i doubt if the savings of 1 million of these "intelligent systems" would undo the unnecessary wastage that ONE solitary BMW X5 V8 (or Merc M class, or any other behemoth SUV)is causing.
    • by mrsquid0 ( 1335303 ) on Wednesday May 13, 2009 @05:53PM (#27945295) Homepage

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

    • 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).

    • So watching your process really will make it finish faster?
  • 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.

  • Overhead? (Score:5, Insightful)

    by bcmm ( 768152 ) on Wednesday May 13, 2009 @04:56PM (#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.
    • 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

    • Re:Overhead? (Score:5, Interesting)

      by tkw954 ( 709413 ) on Wednesday May 13, 2009 @06:40PM (#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.
      • Re: (Score:3, Insightful)

        by cerberusss ( 660701 )

        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.

        You got an 8.78% percent power savings. I don't think that's "nearly neglibible". Maybe you're correct in the absolute sense; what's a 2.8 W power savings? Then I'd say it still isn't too bad.

        And yes, I'm the guy that pulls out the wall warts when not at home.

        • by tkw954 ( 709413 )
          I should have said "negligible when compared to experimental uncertainty". In any case, you're right about the wall wart. I measured a draw of approximately 6 W with nothing plugged into it.
      • The power consumption was 29.1 W [lowest] and 31.9 W [highest]

        That's a 2.8 watt difference. Over a year, that's 88.4 megajoules, or 24.5 kilowatt hours (*).

        Not knowing what your power company charges you, you'll have to figure that out for yourself.

        It's always nice to know whether it costs nickels or dollars :) ... Assuming of course you make the "meaningful" choice to have your system turned on but idle, instead of it being max-clocked and doing make-work. Shrink the dollar amount by your real savings percentage (50%? 10%? 1%?).

        (Of course, trees don't grow on the

  • most people would be happy with something like win9x or win2k (linux for me thanks) on a 750Mhz CPU and 512 megs ram?
    • by Moryath ( 553296 ) on Wednesday May 13, 2009 @05:00PM (#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: (Score:3, Insightful)

        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: (Score:2, Interesting)

          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.
          • by adolf ( 21054 )

            Indeed. Most of the desktop computers at work are 3-5 year old Dell Dimensions with P4 Celerons running XP. And these aren't just idling along: The industry-specific quasi-web-based POS system they run is heavily intertwined with ActiveX, Java, and Acrobat, with bizarre hooks into strange hardware like signature pads, in an environment where time is money.

            We fix them when they break (which isn't bloody often and usually consists of either a software or a power supply failure), and feed them more RAM peri

      • by Moraelin ( 679338 ) on Wednesday May 13, 2009 @05:34PM (#27945103) Journal

        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.

        • 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.

        • by Xyde ( 415798 ) <slashdot@pur3.14rrr.net minus pi> on Wednesday May 13, 2009 @09:04PM (#27946779)
          Chatlog with friend:

          <Me> why does windows software have splash screens
          <Me> for things like, wireless driver software
          <Me> hmm its been sitting here on the screen, frozen for over a minute now
          <Him> or say, your printer
          <Him> i'm so proud of my printer, and assorted accessories that I enjoy having my computer present a tv-sitcom style credits roll every time it starts up
          <Him> oh here is the funny character who pretends to do work, but always is sleeping on the job
          <Him> oh crazy Canon, you're such a character!
          <Him> oh look here comes ATi and some random taiwanese sound chip that looks like a crab
          <Him> what cute characters, they're why I watch this show
          <Him> what would life be like if i didn't have a tray icon indicating to me when I was pushing on the trackpad
          <Him> that's so handy, I always get confused you know
          <Him> am I pushing on the track pad right now?
          <Him> or is it my crotch?
          <Him> i always mix them up, so handy that there is that little on screen icon there all day showing me
          <Him> oh look, there are a bunch of quick to reach options, even though I'd never configure this more than once in my lifetime
          <Him> good thing there are keyboard shortcuts to get here, woah, you know those scroll bars I assigned when I bought the laptop - I need to change those so frequently that I definitely need a keyboard short cut to get there
          <Him> I didn't order crabs with my soundchip
          <Him> and yet, here it is
          <Him> just like crabs: they always come when you don't want them
          <Me> don't forget the horrible interface
          <Me> for 3D sound
          <Me> with lots of bad gradients
          <Him> this menu it needs more over compressed jpeg
          <Him> and all the configuration options need to be laid out as giant long textual choices
          <Him> with tabs
          <Him> oh and can we put a help in there
          <Him> it doesnt need to say thing other than "this option controls a sound option"
          <Him> that's plenty of information for consumers

        • '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.

          Right now I'm using 600 megs out of 2000 (not counting 225 megs of buffers and 872 megs of cache). Sure, the cache speeds things up; could that memory be better spent on caching something else?

          In some cases, I think it makes great sense to cache ready-to-run applications.

      • 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 sys

  • 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?
    • by macraig ( 621737 )

      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....

    • Wake me up when virtual wives are cheap and readily available!

  • 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 . . ."

  • 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 (Score:3, Insightful)

    by sexconker ( 1179573 ) on Wednesday May 13, 2009 @05:04PM (#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 (Score:5, Interesting)

      by tlhIngan ( 30335 ) <slashdot@worf.ERDOSnet minus math_god> on Wednesday May 13, 2009 @05:24PM (#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?

      • 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

      • Re:Waste of Time (Score:4, Insightful)

        by Chris Burke ( 6130 ) on Wednesday May 13, 2009 @07:21PM (#27946067) Homepage

        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.

  • Hmm... (Score:5, Insightful)

    by fuzzyfuzzyfungus ( 1223518 ) on Wednesday May 13, 2009 @05:06PM (#27944817) Journal
    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?
    • 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.

    • by Pulzar ( 81031 )

      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"?

      That's not really the best way to save power for many situations. We already know that the best way to save power is by figuring out the lowest possible speed you can run at and still satisfy the user -- for bursty jobs, or realtime ones, that's easy... you adjust the speed until you get to the point where you're just fast enough to never idle. This is great for graphics chips

    • is this basically a system that underclocks your phone until just before the point where your head explodes?

      No, that would be hald-addon-cpufreq, sometimes gratuitously underclocking my box to one third of its natural speed, making firefox unbearably unresponsive.

      (and thanks a bundle, Ubuntu, for overriding what I asked cpufreqd to do for me, because you of course know better, and thanks again for the ample documentation of hald-addon-cpufreq)

      Thank you for listening; we now return you to your scheduled programming.

  • by idontgno ( 624372 ) on Wednesday May 13, 2009 @05:12PM (#27944873) Journal
    I thought all machines had sensory technology with reacted to the user's activity state. [nmsu.edu] I just look forward to this being used for something besides making the machine malfunction when I need it the most.
  • 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 does

    • by cibyr ( 898667 )

      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.

      • by Mal-2 ( 675116 )

        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

      • how do you take screenshots?

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

    • 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

  • by Capt.DrumkenBum ( 1173011 ) on Wednesday May 13, 2009 @05:20PM (#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.
  • ... using a mood ring to control the CPU? The hippies will love it!

  • 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 ?

  • 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

  • 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.

  • by rickb928 ( 945187 ) on Wednesday May 13, 2009 @06:03PM (#27945389) Homepage Journal
    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.
  • by billcopc ( 196330 ) <vrillco@yahoo.com> on Wednesday May 13, 2009 @06:31PM (#27945645) Homepage

    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!".

    • That should be easier to implement than my previous suggestion [...] F&@#IN' [...] MOTHERF&*@&#$

      Actually, that's pretty simple. There's a sample implementation in /home/larryw/perl/trunk/parser/tokens.c.

  • Time to burn some karma points.

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

    • > 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.

    • by AK Marc ( 707885 )
      Tell me one advantage this knucklehead idea possesses over having a simple slider/dial to adjust processor speed.

      Because a user will always over-estimate the power he wants and the sliders will be stuck in the "most power" setting even when that isn't necessary. So this sets them as to how the user "feels" about the speed, rather than what they think it should be.
  • I peered through the paper, and I don't exactly see how throttling the processor to very low speeds (lower than Speedstep) when idle solves less than optimizing CPU clock speed based on user activity. When properly configured, the speed "bursts" are as short as the burst is needed (i.e. when loading a program, or when compiling), and multiple step levels ensure that the CPU isn't going from minimum to maximum instantaneously (though this behavior can be configured).

    Maybe I just missed the point.
  • Test it on Jim Carrey! Can't wait to see the overlocking results!!!

    .

  • They need to take into account what is being processed in the background too.

    Don't want a compilation slowed down just because you get bored and nod off.

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