ARM Designer Steve Furber On Energy-Efficient Computing 195
ChelleChelle writes "By now, it has become evident that we are facing an energy problem — while our primary sources of energy are running out, the demand for energy is greatly increasing. In the face of this issue, energy-efficient computing has become a hot topic. For those looking for lessons, who better to ask then Steve Furber, the principal designer of the ARM (Acorn RISC Machine), a prime example of a chip that is simple, low power, and low cost. In this interview, conducted by David Brown of Sun's Solaris Engineering Group, Furber shares some of the lessons and tips on energy-efficient computing that he has learned through working on this and subsequent projects."
so why can't i buy a !@##$% low powered computer? (Score:4, Insightful)
That means a portable computer with an ARM processor and a reflective monochrome display big enough to hold normal text pages. In other words an Amazon Kindle DX (separate wired or bluetooth keyboard is fine), but with an open OS that lets me write and run my own programs without having to jailbreak past some DRM crap. Somebody please make something like that? Please??
Re:so why can't i buy a !@##$% low powered compute (Score:4, Insightful)
There are a bunch of cheap 'n cheerful Kindle clones that are supported by the openinkpot firmware, if e-ink is your style.
If you need the refresh rates of an LCD, I think you may have a problem. There is the OpenMoko Wikireader [wikipedia.org] which is super low power and pretty cheap; but the screen(although touch sensitive) is a little smaller than what you want and the CPU is more of a microcontroller [epson.jp] than what you probably want.
You might also consider going the OLPC route. That gets you a rather nice monochrome screen(with backlight color optional) and, while x86, it is a ~1watt embedded Geode, not too power hungry. That one is also by far the most "normal computer" like of the bunch(i.e. no having to code around super slow refresh rates, and running basically standard linux, rather than building binaries for some microcontroller).
Nothing exactly like what you want(that I know of); but there are some approaches...
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I'd tend to suspect, especially if you buy from a seller with a history of other geek junk buying and selling but no major quantity of
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How about using a lightwieght linux distro? You can have a real OS and run it on similar hardware.
Also no, the battery would not go on for days, the cpu would need to be something more efficient than the atom and lighting the screen is probably a much bigger draw.
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Windows 95 is way, way worse than any modern OS, even Vista and Windows 7. Back in the '95 days OSes didn't put the CPU into idle mode and certainly didn't support any power management, effectively running the CPU at full throttle 100% of the time.
Sorry, you made the erroneous assumption that low system requirements equals low power. Try again.
Re:so why can't i buy a !@##$% low powered compute (Score:4, Insightful)
A) Monochrome displays (other than E-ink) are generally considered to be low-tech, cheap, pieces of junk. Look at how well monochrome TVs are selling... Yes, it does ease strain on eyes and increase readability, but has the other side of making most of... well anything unpleasant to look at other than text.
B) It will be expensive. Amazon can afford to produce the Kindle at-cost or even with a bit of a loss because they will gain sales in e-books and such. Even if they sell it at a profit they still can buy parts in bulk and make them cheaper than a product with a run of only ~1,000 units or less.
C) There aren't enough apps. What apps would make sense to port to this device? Lynx? Most other things would need more CPU power (making it non-energy efficient) or a colour screen.
Really, other than you, this wouldn't appeal to a large enough audience of people. Best thing to do would be to jailbreak an existing e-reader, its simply a bad business decision to make a product with almost no market.
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Kindle might have very low computational power, but actually there are some quite powerfull, and can do more than just lynx.
Apps? Just look at where you got lynx from ... And you won't have a shortage
More than just lynx etc. very low computationally intensive? Just look at the chinese netbooks ...
And there you got your actual products aswell
Re:so why can't i buy a !@##$% low powered compute (Score:4, Insightful)
I not so sure, it was not all that long ago most of us who even had a computer were working on an 80x86 or 80x88 with a 512k of memory, connected to a 80x25 character monocrome display, with no network interface, and primary storage consisting of a box next to the unit filled with 360k floppy disks.
You know what we were like pigs in s**t happy too. I have cell phone, not a facy smart phone. I just use it I don't think about it. I charge it Sunday night before I go to bed and I talk and text on it as much as I want to all week long. The batter never goes flat over that time frame.
I had a smart phone for a little while. It could not even stand by all day. I had to go back because I was afraid I might miss SMS alerts from critial systems because the things battery went flat.
I would be very happy with a device that was inexpensive enough to leave on the back seat of my car for weeks on end that would be just there if I needed it and ready to go. Something that could connect to the internet wireless-ly and run lynx and those kinda of apps would be just perfect, even if the screen refresh was slow an e-ink based. Things like e-mail would be very doable as well. We don't live in the same world that 80x86 lived in. There is all kind of infrastructure around, let the POP or IMAP server do the thinking, just add a command like TXTPLZ to the protocols that would instruct the server to render messages sent in other formats out as plain characters. Get send html no problem
becomes 13 and 10. Hell use libcacca to render images as ascii art.
The software you need to write and run on the device could do allot by simply offloading the thinking to the oh lord dare I say it? cloud...
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It's way more than Lynx. There's elm, gopher, nn and with a built-in modem, you should be able to connect to BBS too.
You can. But apparently are unable to use Google (Score:5, Informative)
http://en.wikipedia.org/wiki/Comparison_of_e-book_readers [wikipedia.org]
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Notion Ink has you covered if you can wait until June for their Adam [notionink.in]. It's basically everything you just described, times 9000. And pricing in the bargain laptop range ($350 - $800). I'm not kidding, check it out.
The Kindle's not so bad for this, actually (Score:2)
It's already running Linux out of the box, and the hacks getting everything a unix geek might want on it [boingboing.net] really don't sound like they're about bypassing DRM so much as they are getting tools onto the system that Amazon just left out.
Static link cross compile a telnetd and toolchain and get 'em both on there and you're set to go.
The only reason I haven't bought in on that action yet is that as far as I know there's no decent third party full size portable keyboard. If it did bluetooth, I'd be totally sold. A
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After reading Joseph Jenkin's excellent book, The Humanure Handbook (http://www.jenkinspublishing.com/humanure.html and available for free here: http://humanurehandbook.com/downloads/Humanure_Handbook_all.pdf [humanurehandbook.com]), I've been doing a lot of thinking recently about not just human waste but the waste that comes from everyday computing.
I think what you and I want is the combination of a Beagle Board and a Pixel Qi display (http://www.pixelqi.com/). That display has been mentioned on Slashdot before. You could also
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If it is this latter case, the answer is "mostly no, just lo
Try a "graphing" calculator (Score:2)
Netbooks will make the ARM viable. (Score:2, Interesting)
Thank goodness for netbooks. They will finally make the ARM a viable CPU for use in a wide range of higher-end PCs. We just need to see Windows support for ARM, and then we'll be well on our way towards it being a widely available option.
Frankly, the ARM is a much nicer architecture to target when writing compiler back-ends and when writing high-performance assembly code by hand. It just isn't riddled with the archaic crud that the x86-32 and x86-64 architectures are littered with.
Re:Netbooks will make the ARM viable. (Score:5, Insightful)
We just need to see Windows support for ARM, and then we'll be well on our way towards it being a widely available option.
And you also mean the porting of thousands and thousands of x86 apps as well? If the ARM version of Windows can't run the apps people want, they aren't going to by an ARM netbook.
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Just out of curiosity, while I've done some programming professionally, I haven't touched C or Assembly in well over 15 years, since I needed immediate results and haven't had bosses that allowed anything less, how much work is it to convert something from X86 to ARM? Assuming you didn't write it with the intention of every needing to do so, vs having planned for such a possibility.
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Re:Netbooks will make the ARM viable. (Score:5, Insightful)
You haven't actually ported any non-trivial app, have you?
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Just out of curiosity, while I've done some programming professionally, I haven't touched C or Assembly in well over 15 years, since I needed immediate results and haven't had bosses that allowed anything less, how much work is it to convert something from X86 to ARM? Assuming you didn't write it with the intention of every needing to do so, vs having planned for such a possibility.
Depends on the ARM CPU. ARM7/ARM9 are alignment sensitive. ARM Cortex has a bus/cache interface that allows arbitrary alignment. Porting to the former may be difficult depending on the software, or may simply be tedious, the latter is usually as easy as a recompile if the platform and toolchain is similar (e.g. Linux+gcc).
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Does Cortex still behave like this?
You have a struct { int8_t a; int16_t b; int16_t c; }
It will get layed-out on PPC, SPARC, and X86 like so:
a0bbcc
Will it get laid-out in ARM like so?
a0bbcc00
That's how things were often configured in ARM toolchains because in this way the same sequence of instructions can be used to access an array of such structures, not a different sequence for the ones that are aligned on 32-bits and those that are not. Do you loose the useful rotations with misaligned loads with Cortex
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So I looked a bit and I don't see anything new in cortex that allows to remove this traditional ARM padding.
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And you also mean the porting of thousands and thousands of x86 apps as well?
That's what emulation is for; if MS decides to port Windows to ARM, they'll probably provide an emulator and a shim layer for native calls, and at least support a number of major Windows apps (even though they'll probably run S.L.O.W.L.Y. to begin with). Silverlight and .NET apps should also run more or less out of the box.
Most People Don't Care About Most Apps (Score:2)
And you also mean the porting of thousands and thousands of x86 apps as well?
I suppose there's probably a market for that; there's certainly some subset of the population that's attached to specific desktop applications.
But I'd bet a larger subset of the market just wants to write documents, send/receive email, and browse the web. Ubuntu or some equivalently friendly Linux distribution will do the job nicely there.
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Windows CE has been available on ARM for over a decade.
Besides, I want an ARM netbook because it's NOT a PC and DOES NOT run Windows.
Re:Netbooks will make the ARM viable. (Score:4, Interesting)
And you also mean the porting of thousands and thousands of x86 apps as well?
But most people don't USE thousands and thousands of apps. Or even hundreds of apps. Most people don't even use dozens of apps. You got your web browser and your IM client (maybe), (maybe) an email client, a DVD player, and I bet that's it for the vast majority of computer users outside of work. IM & email clients can be handled by the browser. Seriously - Chrome OS or Android running on a nice 1-2gHz dual-core ARM beast with hardware accelerated HD video w/ 4GB of memory is probably all that most people need at home, as long as it's got a decent screen, keyboard and mouse, they're set.
Download your Android apps, of which there *are* thousands (though many different versions of a much smaller number of TYPES of applications) for expanding into more obscure things. Most of which would be games, of course.
I'd like to see Chrome OS & Android merge sooner rather than later. Absolutely no point in having these be separate projects - with the rise of 'superphones,' there's not that much difference in horsepower anymore, and one platform target is better than two from a developer standpoint (usually).
IMO, anyway. :)
I'm hoping the day when I can take my dual-core 1+ gHz superphone out of my pocket, put it in a dock at home to get a big screen, real keyboard and mouse and true broadband home connection. Shouldn't be more than a year away. C'mon, Sprint, with the Supersonic! I'll fire up the beastly machine when I need to run Photoshop or whatever, but most of the time at home, my computer use is watching TV/movies/websurfing/email.
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So disable them. Not hard.
No one wants to wait. Why in the heck would I want to modprobe in the stuff for my network card rather than wait the tenth of a second it takes to do it on boot?
Re:Netbooks will make the ARM viable. (Score:4, Informative)
Run PowerTOP on Linux (and use a tickless kernel, of course). There are some offenders, but most of those background services aren't using any power. As long as the processes are sleeping most of the time and don't wake up often (once every few seconds at most), they aren't going to increase your power usage.
There are a few slightly annoying ones (ntp tends to wake up once per second, and I think mysql wakes up twice per second), but most of the crap comes from poorly-written GUI apps that poll for stuff or feel the need to wake up tens or hundreds of times per second. Bad user preferences also don't help (hint: anything that's moving on the screen at any sort of framerate while the computer is otherwise idle is going to massively increase power usage over a truly quiescent CPU).
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In some sense that's not a bad thing. ARM was never designed to be in the niches that it finds itself in really. It is low power because it is simple, and it is simple because it started life as a very small RISC architecture. The f
No always has been (Score:4, Insightful)
In the face of this issue energy-efficient computing has become a hot topic
No. That has, and never was the case. The problem is A) Programs now take a lot more CPU usage (compare CPU usage for the same task in Office 2007 and Office 97) B) CPUs are designed primarily to be faster (needed because of point A) C) Battery technology isn't improving as rapidly as the rest of the components.
Look at the Poqet PC of the '80s, it had very aggressive power management which wouldn't work today. Computers have -always- tried to be energy-efficient in the portable sector. And quite honestly, its about the only sector that needs work on energy-efficiency to gain any benefit.
Indeed (Score:3, Insightful)
The phone market has always been looking for ways of extending battery life. I have a phone which is basically a computer with an antenna. It plays videos, music has wordprocessor, gps, maps etc and the battery still lasts up to 3 days.
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isn't that the point - energy efficient computing means software as well as hardware features.
So Office 2007 takes way more CPU and memory to run; all the intensive cloud and web based server apps take a lot of power to cope with peak demand, and so we all run out of energy and end up with brown outs and much more expensive electricity.
When that happens, maybe people will start to take notice and efficient, not bloated, software will become more fashionable. Microsoft will no doubt bring out D# and sell us
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This line of reasoning makes one wonder how much energy it'll take to edit documents with the new iPad versions of iWork, on an iPad with a keyboard attached. Honestly it's something I'm actually considering.
The best subnotebook-like device I ever used in terms of power management was my eMate. I would take that thing to a conference, and in one case actually a business trip to Europe, and not have to charge it until I got home (ie. I got days of use out of it before I had to recharge it). But nobody bui
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Computers have -always- tried to be energy-efficient in the portable sector. And quite honestly, its about the only sector that needs work on energy-efficiency to gain any benefit.
that couldn't be further from the truth. energy costs are just going up. for households it's mildly important as they can usually sleep their computers when not in use. for businesses, energy efficiency ranges from very important to critical when they have massive server rooms full of tens of thousands of CPUs powered and busy 24x7.
moreover, for developing countries, it's again critical. while the L in OLPC stands for laptop and therefore technically qualifies as mobile, it's more about having a battery to
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Google disagrees with you, in a really big way.
Also, anyone who has hooked up a Kill-A-Watt to their computer, and then calculated how much money per year they're spending on it, disagrees with you.
This one asshole [nbc-2.com] spent an estimated half a million dollars (of someone else's money) on electricity (which is probably the main reason he really got in trouble), not counting the harder-to-measure increased
Looking in the wrong places (Score:3, Insightful)
People put too much stock in the home energy savings angle.
I hooked up a Kill-A-Watt to my whole computer/media center stack (computer/monitor/stereo/mixer/external HDDs/assorted electronics), and it was pulling about 65 watts. The only thing that pushed that number up was cranking the stereo.
It costs about 5 bucks a month to leave this stack running 24/7. 5 bucks. If I was to be looking for significant energy savings, I think I would be looking somewhere else.
Want to save energy? Insulate your house.
Noooo!!! Tell me it isn't so! (Score:2)
The Singularity must come!
Real physical limits. Energy production. Getting rid of heat.
Course we could always go nuclear and resume the exponential increase in energy available per individual which has been driving progress for the last 100,000 years, and which stopped in the 1970s (it explains the no flying cars thing, and lack of moon habitats).
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There are 2 ways to increase energy available per individual... Personally I'm hoping we get the whole overpopulation issue resolved first (perferably the humane way), we're kinda screwed overall if we don't.
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There are 2 ways to increase energy available per individual...
Global warming kills 2 birds with 1 stone. More heat=more energy, catastrophic change=fewer individuals.
Ah, the ways of the FSM are mysterious indeed!
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FSM? Heretic! The IPU will get you and you won't even see her coming!
RISC = Good (Score:2)
Re:RISC = Good (Score:5, Funny)
I'm a big fan of arm. I have two of those!
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I still think RISC is the better all around architecture approach. We used to play around with 'chip simulators' by using the plentiful registers in the RISC chips to hold the registers of the smaller RISC chips we were simulating. Great for VM's, too. Ahh, those were the days.
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i like MIPS... in college, we had one semester of hands on lab work learning everything about a specific MIPS implementation, then another semester writing a compiler capable of compiling itself for the architecture.
once you can grasp the simplicity and understand exactly whats going on in the chip, features like HyperThreading seem almost stupid because of how much complexity and exceptions they add to the system.
Of course modern MIPS processors are threaded as well...
The funny part is newer computers are more (Score:5, Insightful)
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I doubt it (Score:3, Funny)
If the unit of computation is to put a single character on the screen for example. Today, it requires several supercomputer class processors to do the same job as one 286 during the 80s.
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but now we have cuved edges and smooth colors - and wait.. still using a square dot to show it.. crap
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efficient. I mean if you consider any unit of computation vs energy expended. I bet my current desktop computer would compare from a computation point of view to a super computer from the late 80's. (GFLOP to GFLOP) However my current computer pulls about 300W, I'm pretty sure that's alot better than any super computer from the 80's that would compare to it.
300W? I'm pretty sure a coffee maker from the 80's was even that efficient.
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My Athlon II X2 + 8800GS pulled 95w from the wall, according to my Kill-A-Watt.
Now I have a Phenom II X4 and GTS 250. It pulls about 107w from the wall when idle, and as much as 160w when gaming. (~175w when encoding video)
The funny thing is, I've seen old P4 computers drawing 250w+.
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And late model PIII's, (which were smoking the early P4's) only sucked 30-40W at the die. Netburst was just a big fail in general. A slow flamethrower.
Begging the Question (Score:3, Interesting)
while our primary sources of energy are running out
Just cleaning up our light-water reactor waste (which we cannot leave around for 300,000 years) can power the Earth's advancing societies for a century.
There are much better reasons to go for low-power computing, portability and economics chief among them.
It's just marketing (Score:3, Insightful)
Aka lying.
While it is true that according to best estimates oil is going to become rather scarce in the not too distant future, oil isn't a major provider of power. It is used for power generation, but not near as much as others. Coal and nuclear are the heavy hitters in power generation and both are still extremely abundant. So while we need to consider what will fuel our cars, we are not approaching a situation where the lights go out.
He's just trying to jump on the green bandwagon to hype up his product
Connectivity and standards are the solution (Score:2)
If Internet connectivity were ubiquitous and cheap and proper standards were developed and encouraged, we would see a tremendous improvement in efficiency.
1. It takes a very minimal amount of power to use hosted applications, so the end users devices would be low power.
2. Data centers have serious incentives to be efficient, when your annual electric bill is in the $100,000+ range, even a 1% improvement is worth considering, when was the last time you cared about saving 1% on your electric bill.
The WWW is g
Make Boots & Scans Faster (Score:2)
1) Because boots take a long time. If boots were near-instant like they were on my TRS-80 in 1979 I'd turn it off. (Yeah, yeah, Macs boot fast, yeah yeah, I can 'suspend' but none of that junk ever works properly on WinTel.)
2) Because backups, patches and scans run at night time. If I didn't need those, I'd turn it off.
Figure out a solution there and I'd turn my box off.
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I can 'suspend' but none of that junk ever works properly on WinTel
every computer i've owned or used in the last 10 years has been able to hibernate or sleep. that includes macs, linux and win98 to win 7. if you buy a computer that can't reliably sleep, you should return it and get your $ back.
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Hard to run cron jobs while the machine is sleeping.
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yeah yeah, I can 'suspend' but none of that junk ever works properly on WinTel.
Yah it does. Unless your computer's defective. If it's defective, take it back and get one that works.
Seriously, suspend/hibernate is a solved problem for the last decade. When's the last time you tried it? Windows 98?
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When's the last time you tried it?
Last week.
My (c) 2005 gateway (XP) has no audio when it comes back from sleep. My Dell Inspiron PIII has a Linksys WiFi card in the PCMCIA slot. The card dies when it goes to sleep and only comes back with a reboot.
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How many bytes was the OS on a TRS-80?
You can't really compare that...
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How many bytes was the OS on a TRS-80?
The computer 'booted' to a BASIC interpreter at the command line:
READY
>_
Energy running out (Score:2)
while our primary sources of energy are running out
And in the 1920s, they claimed we were running out of oil. In the 1970s, they claimed we were running out of oil. Just last year they found a new oilfield off of Brazil bigger than anything found yet. Last year. After everyone said no new large fields would ever be found.
Coal? Clinton locked up the Grand Staircase in Utah, the largest clean coal deposit, with 62 Billion tons of coal [utah.gov].
I don't know. I hate scare-mongering that has been going on already fo
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We're not likely to run out soon, it's just going to get expensive.
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Even if it does, we don't need the government to save us preemptively from expense (be it healthcare or energy). In both cases reducing red tape is 80% of the solution. I'm tired of being rescued. Just get out of the way.
(Please realize that this post is just a personal rant and has little do do with the parent. He just offered a nice jumping point.)
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On the first I agree, but there is no such thing as clean coal. That is just a marketing stunt.
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Just last year they found a new oilfield off of Brazil bigger than anything found yet. Last year. After everyone said no new large fields would ever be found.
The Tupi field is estimated to hold 8b barrels of oil. Given our current global consumption that's a three month extension. It's the biggest field discovered in 30 years - which is pretty telling. Find ten of these and we've got a few extra years. Find only another one or two and it makes no difference. Meanwhile, when the global business cycle points up again our oil consumption is going to follow likewise - again. Prices will rocket, and economic growth will be choked. Oil is really a limited resou
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Either that is the best racist troll yet, or Crazytown has a new mayor.
Wierd priorities (Score:2)
My computer? Really? THAT'S the power hungry device I should be worried about? What about, oooh, I don't know, how about my electric clothes dryer with the 240V plug and the massive double circuit breaker in my breaker box?!
Priorities people, priorities.
Fearmongering. (Score:2)
Set up a couple of solar thermal power plants (e.g. in Arizona), lay a couple of high-voltage DC lines, or convert it to hydrogen, or any form or battery, and be good. We will have left this planet, long before we use more energy than the sun can deliver (especially when you add space-based power plants). And the technology is cheap, simple (a poor African nation could do it without having to having to take a loan), recyclable, and there is a lot of really dead and hot land out there (certainly deader than
Re:Fearmongering. (Score:5, Interesting)
For less than the cost of the financial stimulus package, or the Iraq war for that matter, the US could produce almost all it's electricity with solar thermal plants with present level technology (and the cost for plants would probably be quartered by the time you are done because of economies of scale, so it would cost far less). Hugely reducing electricity costs in the US would probably do more for the economy than just about anything else the money could be spend on.
As a European I'm envious ... the US really has it all, virtual dead deserts with round the year sunlight, a reserve currency which gives you nearly limitless free money to spend on these kinds of projects, and hell quite a nice supply of oil reserves as well ... it's frankly a miracle how your politicians manage to fuck that kind of potential up.
Cloud computing is energy efficient (Score:2)
Re:Energy Efficient Tips (Score:4, Informative)
(record the uptime with a pen+paper if you want to keep a running total)
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For a couple of decades?
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Really ?
In our serverroom we have a few which don't get as many security updates (internal systems), they are doing fine, thank you.
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Use ksplice. done.
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For me it is hard to find a year that does not have a long (at least 35 minutes, the time it takes my UPS to discharge) power outage.
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Every two years is not that long really.
Re:Energy Efficient Tips (Score:5, Insightful)
Bit shift instead of multiply by powers of two
I'd think a decent compiler should do that automagically, no?
Re:Energy Efficient Tips (Score:4, Funny)
Maybe he means you'll save the energy the compiler would spend to optimize a multiply into a bit shift :-)
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Use floats where doubles aren't necessary
That assumes that floats are more energy efficient than doubles. Not necessarily true on architectures that have hardware floating point and save energy by omitting the float portion. They convert the float to double, do the math, then convert back. Check your architecture!
On my Intel Core 2, the execution speed is different by about 0.06% between float and double (edge to double). Can't speak to power consumption though. On my Intel Atom 230, the floats are faster by 0.4%. That's almost certainly sav
Re:Energy Efficient Tips (Score:5, Informative)
Actually, you're only half right. On ARM, there is typically no double hardware, so you get a very slow path for 64-bit floating point arithmetic. On your Core 2, it's more complicated. The x87 unit only supports 80-bit floating point values. This means that any float or double will be sign-extended when it is loaded into a register. You gain a bit better cache usage from using 32-bit floats, but that's it.
No both, however, if you compile with SSE then you will be using a vector for all floating point operations. With floats, the compiler can pack concurrent operations on four of them into a single instruction, with doubles it can only pack two. I'm not sure about the Atom, but I vaguely remember that it splits SSE ops in half, so you really do two 64-bit operations. Either way, you can do twice as many float operations in the same power envelope, as long as your code is suited to vectorisation.
Modern compilers prefer to target SSE instead of x87, because register allocation with x87 is painful. Most operations only work between the top two registers in the 'stack' so you need a lot of register-register copies in a typical bit of x87 code (which burns i-cache too). This is one of the main reasons why you see a performance improvement in x86-64; if you have a 64-bit chip you can guarantee the presence of SSE, so the compiler will always use SSE instead of x87 when compiling 64-bit code. If you're someone like Apple and don't support pre-SSE chips, you can also do this and get the same benefit in 32-bit mode.
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Your credibility as a reference was lost when you fail to expand the ARM chip acronym correctly.
Hey, on Slashdot old school [wikipedia.org] is acceptable.
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It was Acorn RISC Machine way before it became Advanced RISC Machines Ltd; by almost a decade, when Furber ran the show.
Re:where do you get your facts? (Score:5, Informative)
Re:where do you get your facts? (Score:4, Interesting)
I worked at Acorn in the early 80's and knew Steve Furber, but it's amusing to think that most of the Slashdot crowd probably wasn't even born then. I assume the average age here nowadays must be college age or thereabouts.
Not surprising they don't know what ARM originally stood for.
Re:Bull... (Score:4, Informative)
Look up "Energy Return on Energy Invested".
Saudi oil has been 100:1.
Shale... 5:1 maybe, 3:1.
http://en.wikipedia.org/wiki/Oil_shale [wikipedia.org]
When they really start using shale, you know the shit is really hitting the fan.
And no matter how much is left (quoted in the reserve figures as recoverable), could be a trillion trillion barrels, nobody is going to bother trying to get it out when it takes a unit of energy in to get a unit of energy out.
Re: (Score:3, Insightful)
Only if you're assuming energy cost is the primary cost.
Re:Bull...you are not even counting coal (Score:2)
We have over 250 years worth of easily available coal here in the US.
Re:Bull...you are not even counting coal (Score:5, Informative)
Nasty, dirty shitty coal. Coal power should just be illegal already.
Nuke, wind, solar, natural gas all are alternatives with far less pollution and co2 release.
Re: (Score:2)
And how much do you have to pay to make a modern x86 chip under licence?
The physical chips are definitely cheaper than anything x86 with similar speed.