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DARPA Looks Beyond Moore's Law
ddtstudio writes "DARPA (the folks who brought you the Internet) is, according to eWeek, looking more than ten years down the road when, they say, chip makers are going to have to have totally new chip fabrication technologies. Quantum gates? Indium Phosphide? Let's keep in mind that Moore's Law was more an observation than a predictive law of nature, despite how people treat it that way."
First they want to get around privacy laws, now they want to break Moore's law...these guys have no bounds!
"It takes considerable knowledge just to realize the extent of your own ignorance." - Thomas Sowell
perhaps stacked wafers with vertical interconnects might help... I'm not sure how you'd dissipate the heat, though.
Moore's law, bah! Thinking about it, DARPA should get Steve Jobs on board to study his Reality Distortion Field. Think of the military aspects of.......oh, wait. We already have that.
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It's just a wild guess. It has absolutely nothing to do with physics, which is the real laws we all live by. It has much more to do with human laws such as patents and copyrights that limit progress.
-Libertarian secular transhumanist
I"m pretty excited about the new man-made diamonds that are supposed to be able to keep moore's law going for decades when they come out. Wired had an article recently and a post here on /. too
This diamond article in Wired 'http://www.wired.com/wired/archive/11.09/diamond. html' seems to indicate that Moore's law is sustainable for much more than ten more years.
Besides, I've been hearing about the death of Moore's Law for the last ten years.
"The market alone cannot provide sufficient constraints on corporation's penchant to cause harm." -- Joel Bakan
Let's keep in mind that Moore's Law was more an observation than a predictive law of nature, despite how people treat it that way.
Let's not and say we did.*
Seriously, I doubt that many people think that Moore's law is on an equal footing as say gravity and quantum mechanics. Still, an observation that has held more or less for nearly 40 years is worth considering as a very valuable guideline. Let's keep this in mind as well.
(*Why do vacuous comments like this make it into slashdot stories?)
This idea of speeding up processing speed is barking up the wrong tree and ultimately doomed to failure. We need to be focusing our attention on biochemistry and molecular biology. We already have drugs that slow your reaction time, thus making things appear to happen more quickly.
See, if we get everybody to take xanax or zoloft, there's no limit to how fast computers will appear to be working.
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Every 18 months, someone will develop a new law to compute the rate at which the estimate of the rate at which the number of transistors on semiconductor chips will double will halve.
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You aren't being forced to do anything... you simply choose to do it to keep up with the times. Many consider this "progress".
The unofficial
Computer salesmen are using it like a club. You figure it would drive innovation, instead of driving CPU manufacturers take advantage of comsumer ignorance and do fairy magic with clock speeds. We should call it "Moore's Observation".
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An educated observation, which is why it basically works.
Please note that the observation was well enough educated that it includes the fact that its validity will be limited in time frame and that before it becomes completely obsolete the multiplying factor will change, as it already has a couple of times.
In order to understand Moore's Law one must read his entire essay, not just have some vague idea of one portion of it.
Just as being able to quote "E=mc^2" in no way implies you have the slightest understanding of the Special Theory of Relativity.
KFG
> The Bush Method: all you have to do is take the thing about reality you want to distort, and state that it has changed, whether or not it hasn't
Why do you give Bush the credit? This shit is Marketing 101 and Politics 102.
The unofficial
Moore's law is already ending. Intel's Prescott (i.e. Pentium 5) CPU dissipates 103 watts. That's beyond anything you can put in a laptop, and it's arguably beyond anything that should be in a workstation-class PC. But it also may not be that we're hitting CPU speed limits, just that we're hitting the limits of type types of processors that are being designed. Much of the reason the PowerPC line runs cooler than the x86 is because the instruction set and architecture are much cleaner. There's no dealing with calls to unaligned subroutines, no translation of CISC instructions to a series of RISC micro-ops, and so on. But there are the same fundamental issues: massive amounts of complexity dealing with out of order execution, register renaming, cache management, branch prediction, managing in-order writebacks of results, etc.
Historically, designing CPUs for higher-level purposes, other than simply designing them to execute traditional assembly language, has been deemed a failure. This is because generic hardware advanced so quickly that the custom processors were outdated as soon as they were finished. Witness Wirth's Lilith, which was soon outperformed by an off-the-shelf 32-bit CPU from National Semiconductor (remember them?). The Lisp machine is a higher profile example.
But now things are not so clear. Ericsson designed a processor to run their Erlang concurrent-functional programming language, a language they use to develop high-end, high-availability applications. The FPGA prototype was outperforming the highly-optimized emulator that had been using up to that point by a factor of 30. This was with the FPGA at a clock speed of ~20MHz, and the emulator running on an UltraSPARC at ~500MHz. And remember, this was with an FPGA prototype, one that didn't even include branch prediction. Power dissipation was on the order of a watt or two.
Quite likely, we're going to start seeing more of this approach. Figure out what it is that you actually want to *do*, then design for that. Don't design for an overly general case. For example, 90% of desktop CPU use could get by without floating point math, especially if there were some key fixed point instructions in the integer unit. But every Pentium 4 and Athlon not only includes 80-bit floating point units, but massive FP vector processing units as well. (Not to mention outmoded MMX instructions that are almost completely ignored.)
But also thousands or hundreds of thousands of times smaller than going outside the package; which would make it ideal for multi-processors, array processors, or large local caches.
They made an announcement about it less than a year ago. They don't say if they'll be doing anything special about heat problems, though.
Thank Goodness someone has finally said something about it, even if it was just in passing. The bonus is that it is on the front page of Slashdot.
t m
"Moore's Law" is no more a "law" in the sense of physics (or anything else for that matter), than any other basic observation made by a scientist or physicist.
Oddly, you'd have a hard time believing it wasn't a Law of Nature by the apocalyptic cries from the technology industry when "Moore's Law" falls behind - spouting that something *has* to be done immediately for Moore's Law to continue, lest the nuclear reaction in the Sun cease. Or something.
At the time it was coined by the *press* in 1965, only a small fraction of what we now know was known about the physics of integrated circuits and semiconductors at the time. So, looking back it's easy to see that the exponential trend in density would continue as long as the knowledge and abilility to manipluate materials increased exponentially.
Yes, it is rather surprising that Moore's observation has held true as long as it has. And this isn't to say that the growth trend won't continue, but it will certainly level off for periods while materials or manufacturing research comes up with some new knowledge to advance the industry.
As the article indicates, things are likely headed for a plateau, possibly toward the end of this decade or start of the next. And at that point, Moore's observation will simply no longer be true or appropriate.
Let the cries of armageddon begin as "Moore's Law" is finally recognized as an observation that will eventually be outlived.
For a little "Moore" background, see http://www.intel.com/research/silicon/mooreslaw.h
Think about this: Why is video graphics hardware so much faster than CPU's? You might say that it is because the video card is specifically designed for one task... however, these days, that isn't really true. Modern video cards allow you to write small -- but arbitrary -- programs which are run on every vertex or every pixel as they are being rendered. They aren't quite as flexible as the CPU, but they are getting close; the newest cards allow for branching and control flow, and they are only getting more flexible. So, why are they so much faster? There are a lot of reasons, but a big one is that they can do lots of things at the same time. The card can easily process many vertices or pixels in parallel.
Now, getting back to C... A program in C is supposed to be executed in order. A good compiler can break that rule in some cases, but it is harder than you would think. Take this simple example:
This is just a piece of C code which takes a list of numbers and produces another list by adding one to each number.
Now, even with current, mostly-serial CPU's, the fastest way to perform this loop is to process several numbers at once, so that the CPU can work on incrementing some of the numbers while it waits for the next ones to load from RAM. For highly-parallel CPU's (such as many currenty in development), you would even more so want to work on several numbers simultaneously.
Unfortunately, because of the way C is designed, the compiler can not apply such optimizations! The problem is, the compiler does not know if the "out" list overlaps with the "in" list. If it does, then the compiler has to do the assignments one-at-a-time to insure proper execution. Imagine the following code that calls the function, for example:
Of course, using the function in such a way would not be very useful, but the compiler has to allow for it. This problem is called "aliasing".
ISO C99 provides for a "restrict" keyword which can help prevent this problem, but few people understand it, even fewer use it, and those who do use it usually don't use it everywhere (using it everywhere would be too much work). It's not a very good solution anyway -- more of a "hack" if you ask me.
Anyway, to sum it up, C generally requires the CPU to do things in sequence. As a result, CPU manufacturers are forced to make CPU's that do one thing at a time really, really fast, rather than lots of things at the same time. And, so, since it is so much harder to design a fast CPU, we end up with slower CPU's... and we hit the limits of "Moore's Law" far earlier than we should.
In contrast, functional languages (such as ML, Haskell, Ocaml, and, to a lesser extent, LISP), due to the way they work, have no concept of "aliasing". And, despite what many experienced C programmers would expect, functional languages can be amazingly fast, despite being rather high-level. Functional languages are simply easier to optimize. Unfortunately, experienced C/C++/Java/whatever programmers tend to balk at functional languages at first, as learning them can be like learning to program all over again...
So, yeah. I recommend you guy