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If the L1 suffers a miss while the power manager
is on and the processor is flushing its L2,
some L2 lines may get corrupted.
[Signal condition: L1WAITMISS & DPM (dynamic power
management) & L2FLUSH].

It's for fixing design defects after the design is frozen. Similar in concept to the microcode patches that Intel and AMD use for patching certain problems with their processors, but much more versatile, and specifically targeted at the most common types of design defects, according to the original paper:
http://iacoma.cs.uiuc.edu/iacoma-papers/micro06_ph oenix.pdf

An anonymous coward replied to my post below with this link to the original paper:
http://iacoma.cs.uiuc.edu/iacoma-papers/micro06_ph oenix.pdf

Basically, the idea is to include a small amount of reconfigurable logic on a conventional microprocessor. The configurable section would be used to detect conditions that trigger known design defects (or errata, as they're called in the industry), and work around the problem. The authors figure that for about 0.5% overhead in wires and silicon area, a chip manufacturer can patch around more than 60% of typical errata conditions.

The paper describing Pheonix has won some noteworthy awards:
* Best Paper Award, MICRO 2006, December 2006
* Also appears in the IEEE Micro Special Issue: Micro's Top Picks from Computer Architecture Conferences, Jan-Feb 2007

A quick google search sends you to his UIUC homepage http://iacoma.cs.uiuc.edu/~torrella/ where you can read the full paper. C'mon guys, he's a prof at UIUC, he's not going to announce he invented the FPGA, part II. The paper's actually pretty interesting

"I can't tell if the stupidity is in the article writer (most likely) or the researcher."

Wrong. I believe that the stupidity is in the Slashdot readers. Dr. Torrellas published this in Micro-39, which means that the paper has been floating around the internet for around 4-6 months. You should assume that article writers are going to screw up the details. Go read the paper yourself. Here's a link:

http://iacoma.cs.uiuc.edu/iacoma-papers/micro06_ph oenix.pdf

Then, if you feel so inclined, go read other modern papers to see exactly what the other new things on the horizon are. Go to Google, search on some computer architecture conferences (ISCA, MICRO, HPCA, ASPLOS, etc), then read the papers listed in the conference proceedings. You can find them using most search engines (Try Google Scholar).

Then, after reading the source, come to Slashdot and bitch intelligently. After all, if you don't -- aren't you just gossiping about your friend's brother's sister sleeping with that other guy with the gross body odor? Yeah right, like she'd hit that.

*rolls eyes*

And people wonder what's wrong with slashdot.

Read about the man before you put your foot in your mouth again.

I suppose you all could go to the source.

I wish the article would mention more about why it is better than similar techniques that have been proposed in the past. (For example, http://luthuli.cs.uiuc.edu/~daf/papers/WAP-fin.pdf seems similar) For instance, where do they get their labels for the training data? A lot of people have tried using contextual words drawn from surrounding web text to limited success due to noise. It's also questionable how well their techniques can do if they need to pre-build a separate classification for each keyword. Finally, there are words that it seems impossible that they could ever distinguish. For example, 'man' vs. 'woman,' would be incredibly complicated for anything but a human. Where are the details? Oh yeah, it's a news story! Here's a link to the paper http://www.svcl.ucsd.edu/publications/journal/2007 /pami/pami07-semantics.pdf

http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/cr ls.rxml

The link above explains the Coriolis force. Among other things, this is the force that causes water to spiral down the drain in different directions on different sides of the equator. It also manifests itself such that if you fly at sufficient speed travelling past 63 deg. North Latitude, you will feel a slight bump. This is easily measured and confirmed by placing an accelerometer on the aircraft. There is almost always a slight acceleration. Of course, the accelerometer is subject to the vibration of the aircraft and to rapid changes in altitude due to air currents so the bump is often lost in the noise floor but it's there nevertheless.

The phenomenon cited above is not limited to any particular time and is somewhat south of 80 deg. North Latitude but I suspect that Ignatiev is probably talking about the same thing. He should check his math.

And I'm all for the scientific method. Empirical observation leading to theory which can be confirmed, or denied, through thorough testing and peer review. One, two studies still do not a fact make. The outcome as presented here could as be influenced by numerous factors -- gender bias, as shown in a study, isn't necessarily all in the mind of a biased person, but can be the result of societal influences on either gender, for instance:

http://lrs.ed.uiuc.edu/wp/access-2002/gender_bias. htm

Again, my response was to the question posed in the summary. Your response, as far as I can determine, was only to the need of your own ego to try to "one up" some anonymous person you've never met, over the medium of the Internet. Get a life. Respond in context. I'm done here.

At the last GECCO conference I saw a paper presented on the use of a genetic algorithm to speed up the simulation of certain chemical reactions:

linky
Google cache because the link is to a power point...

Basically, a multiobjective GA was used to find parameter sets for chemical simulation equations that increased the speed of those simulations by a factor of 10x-103x. (And were more accurate, to boot.) That enables the reaction models to be more complex and, as the presentation stated, "lead potentially to new drugs, new materials, fundamental understanding of complex chemical phenomena."

Cool stuff.

Or how about growing miscanthus (and/or switchgrass) for ethanol instead of corn? Much better energy return, much kinder to the soil, much cheaper to farm.

I'm amazed that nobody has mentioned the Practical End-host collaborative Residential Multihoming framework (PERM). From the site:

802.11 networks have spread rapidly in the residential area, and it is common for neighbors to receive signals from each other's home wireless networks. PERM allows residents to leverage such an opportunity to improve their last-mile Internet connectivity, at no additional cost, by pooling their Internet accesses together. PERM is practical in that it does not rely on support from the network infrastructure in terms of advanced naming scheme or proxy, the remote host in terms of new transport protocols, or the end-user in terms of explicit application feedback or configuration. Instead, PERM employs automated on-line analysis of the user's networking behaviors, and exploits the identified patterns to achieve high-performance scheduling at the flow level. PERM is also highly usable for normal residential users. It preserves a user's privacy and security, and mitigates the free-riding problem. We have implemented PERM for Linux clients and the open-source Linksys wireless router.

Aviation cockpit designers think hard about this stuff. They refer to it as "head-down time", the time the pilot is looking at something else in the cockpit and not out the windscreen. In combat, this is fatal. Hence the military emphasis on heads-up displays and HOTAS (Hands On Throttle and Stick) input devices. In civilian aircraft, cockpits are designed to minimize head-down time at least during takeoff, approach, and landing.

Much automotive and civilian gear is terrible by these standards. Cockpit designers insist on big knobs you can set by feel and interfaces that minimize head-down time. They try hard to avoid interfaces with unneeded state, and ones where you have to look to see what state you're in. BMW's iDrive was terrible in this regard. BMW's answer was to include a disclaimer that it was unsafe to operate iDrive while driving. Really.

One design feature that can kill - an interface which times out. The pilot/driver must be able to stop dealing with some cockpit gadget without losing any work. Phones/keyboards/dashboard devices that time out during data entry are dangerous, because they train the user to give them undivided attention. Some phones have this problem, and some don't. Texting has this problem.

"Nothing to watch but the road" - early Oldsmobile slogan.

The phenomenon you're referring to is called inattentional blindness. The demo of it that you're referring to (the gorilla suit guy) is located here: http://viscog.beckman.uiuc.edu/grafs/demos/15.html

The importance of this effort was underlined by the fact that Walt Kelly's "Pogo" sent it up. Since the event was a "year" of 18 months, Pogo suggested naming the extra months after foods -- Octoberry, Novemberry etc.

In a side note, the US response to Sputnik included a science payload named Nora-Alice 1, beacon transmitter for Discoverer satellite, which took it's name from a poem Pogo wrote in honour of the IGY. http://www.ece.uiuc.edu/about/history/reminiscence /space.html/ has a picture and a small quote down the column a bit.

So as you can see, drilling a hole in the Earth past the crust to the mantle inspired some of the first orbital satellites. Remarkable! Oh, and then there was LAGEOS, of course, but I'll let you look that one up.

It's a funny video to show to your friends and test their visual perception.

I've found about it through growabrain: White Shirt Experiment

Here's the actual video (Java Plugin required)

Carnegie Mellon is not that great a school for EE/CE. Try the University of Illinois at Urbana-Champaign as they consistently rank in the top 5 schools for EE/CE/CSE/CS.

Going to UIUC is around $22,144 per year ($598 ~ $681 per credit hour) so expect to pay...
at least $81,920 for a BSEE.
at least $86,400 for a MSEE.
at least $120,960 for a DEE.

If I were you... I'd go to my local community college for an AS in physics then transfer to UIUC. Doing this substantially reduces the costs...
$42,000 for a BSEE.
$52,000 for a MSEE.
$86,000 for a DEE.

If you go this route, and keep your grades up, you can get into any school of your desire.

Another smart thing to look into is a postgraduate degree from the Air Force Institute of Technology, as a commissioned officer... If you did this you'd get to work with really cool shit (stuff you'd never get to play with in the civilian world) and get paid for going to school!!!

Tachyon [http://jedi.ks.uiuc.edu/~johns/raytracer/]

Site may be down so look for mirrors.

The University of Illinois lets you get a mini-Master's degree online. They call it a "Master of Computer Science" degree to differentiate it from their traditional Masters, which is called "Master of Science in computer science." The online degree is inferior because it doesn't require seminar work or a master's thesis, but the coursework is the same.

This used to be on youtube, but it's been pulled. It's now up at a safer place. Some local people I know have actually been able to deduce locations from the video and obtain a couple of these "devices." Boston area slashdotters up for some scavenger hunting? athf-lightsnipes-boston.flv

You would be surprised... we are already there.
http://graphics.cs.uiuc.edu/svn/kcrane/web/project _fluid.html/

Full water is a ways off since it requires a large area to be simulated (well, you can simulate puddles, but not anything you can swim through). However real smoke animates are on their way since you can easily confine smoke to a reasonably small area. Nvidia's smokebox demo was created to show off the 8800's processing power with realistic smoke rendering, and the results of that demo are already being integrated into games. Movies more information are on the creator's website:
http://graphics.cs.uiuc.edu/svn/kcrane/web/project _fluid.html
http://www.gametrailers.com/player.php?id=15381&ty pe=mov&pl=game

To save some of you from googling: linky

I think some public schools might disagree.

And if you look worldwide, rather than at just the Atlantic, they were, this last season.

The Atlantic didn't have many hurricanes, which is usual in an El Nino year.

I found a good solution, besides using viper mode.

I'm using AccessX's sticky keys.

Works great!

Edlin is obviously the best.

Yeah Edlin's not bad for a 6 month quick fix in QDOS which is still available as the *same* version in Vista ! Microsoft certainly know how to resell code ;-)

I miss these old editors which had many uses..... With regards to VI for example my friends and myself used to use it to clear out a.out files under rsh (That's RSH as in Restricted SHell under System 4 and NOT Remote SHell)! Mind you that was before we worked out the far simpler command "time csh" which obviously is just a helpful command to time how long you spent in the CSH shell when you ussed that command to start CSH from the RSH shell.... :) Yes, VI helped many people free themselves of the shackles of certain restrictive shells....

I remember that a while ago some PS2s with Linux were used in some scientific settings for certain vector calculations, I believe (I only skimmed the linked article...I saw this on The Screen Savers a while back). Would the PS3/Linux combo be an even better replacement? They're expensive as hell, but I would imagine much faster.

It's mostly for developers right now (hey, it's even in the correct Slashdot category!).

Personally, I think Japan is building a gigantic supercomputer out of PS3s ;) When Linux got onto PS2, the most common usage for them were clusters. Here's a picture. I can only imagine what a rack full of PS3s can do. Of course, like the PS2, the PS3 is subject to restrictions. From the PS3 EULA:

Have to make sure those Albanians aren't cracking RSA or some such thing.

mandelbr0t

Google is your friend (and so are college students!)

Laptop battery usage report

Bill Gates isn't my enemy -- I don't (really) want to destroy him. Neither is Steve Ballmer.

<rant class="awful" title="Final Sanctimony Of 2006" style="presentation: preachy;">

Recognizing both of these guys as enemies is better than regarding them in any other way. Bill Gates' public history is littered with debris of the destruction he has caused to people who were his allies and partners: I would risk the safety of things I hold dear if I regarded him as anything other than an enemy. From statements in the public record, there is no doubt that if Steve Ballmer knew me personally, he would be threatening to "fucking kill" me.

Slashdot is full of people who want to emulate one or the other of these guys. They've got a word for people who see the world the way parent post describes it: suckers.

Enemies want to destroy each other.... I don't (really) want to destroy him.

Ah-hah! There is the problem; a simple but very basic mistake in how one should interpret reality.

It isn't about you all the time, you know. Do you really think that if you decided that Gretchen will be your lover, all of a sudden she will enthusiastically come to your bed? You actually have less say in who shall be your enemy than you do in who might become your lover. Failure to recognize that the other person has a lot to say about either relationship is not a good basis for one's view of the world.

No, Grasshopper, in this life you do not get to choose your enemies. You get to choose what principles will guide your behavior. You will then find that your enemies will choose you. If you are resourceful, careful, attentive, and very, very lucky, you may be able to choose your battles. But not your enemies; they will choose you.

Now enmity is another thing entirely. Avoid it, along with hatred, hostility, and all those associated feelings. Treat your enemies dispassionately, even in the midst of battle. For unless you are actually involved in hand to hand combat, there is no place for the intense concentration and focus, the tunnel vision and imperviousness to pain and injury, that are the hallmark of these emotions.

Invest your passionate energies in your friendships and loves; don't waste them on your enemies.

</rant>

Desiderata

Reality Check 101.

The Slashdot Geek is not Microsoft's core market.

What about in ten years, when said Slashdot Geek has long graduated from university and gets promoted to a position where they can start to make purchasing decisions? (Apologies to those with 4-digit UIDs, who may already be old enough for this to have happened.)

Along this line, I should probably also mention that in my CS classes, what looks like at least a quarter (and more likely a third) of the laptops people bring to class regularly run some version of Linux. And when we had a ACM-hosted conference a couple months ago, I'd say that over half of the laptops people had were running Linux.

Your employer likes the idea of Trusted Computing.

Separate issue. And I rather suspect that OS-level trusted computing would be Good Enough, particularly since hardware-level trusted computing (1) is only important if you don't trust the OS, and (2) ties things to specific pieces of hardware, which can fail.

One of the predominate motivations for French policy toward nuclear weapons and French international policy in general stems from Charles de Gaulle and his idea of an independent nuclear striking force or force de frappe. Initially, it was de Gaulle's Provisional Government that laid the grounds for development of nuclear weapons with the creation of the Commissariat a l'Energie Atomique (Atmoic Energy Commission) in late 1945. This set the stage for later decisions by de Gaulle about France and her defense strategy.

Charles de Gaulle firmly believed that France needed to remain politically independent from all other countries. He also believed that in order for a country to truly remain independent it needed a strong defense force. More importantly, the defense force must also be independent. To support this claim, Gough has quoted de Gaulle as saying, "The defense of France must be French." It was this type of reasoning that led de Gaulle to be a driving force for the independent development of nuclear weapons, even when he was not in office, in order to have an independent nuclear force.

Official approval for developing nuclear weapons was not authorized until late 1954, even though by then the necessary plutonium production program was well advanced. Following the route of French forces at Dien Bien Phu, and the loss of then French Indochina, France's interest in nuclear weapons to bolster its national prestige took a sharp upswing. On 26 December 1954, Prime Minister Pierre Mendes-France met with his cabinet and authorized a program to develop an atomic bomb. On 28 December a new Bureau of General Studies (Bureau d'Etudes Generales) was created with General Albert Buchalet as head to pursue this option. In 1955 the Armed Forces Ministry (Ministre des Armees) began transferring funds in large amounts to this program.

And I thought I sucked at math when I couldn't remember how eigenvectors work the other day...

The numerical solution of differential equations, notably the Navier-Stokes equations was an important stimulus to computing, with Lewis Fry Richardson's numerical approach to solving differential equations. To this day, some of the most powerful computer systems of the Earth are used for weather forecasts.

http://www.eslarp.uiuc.edu/arch/ARCH371-F99/groups /k/solar.html probably too late in the day for this to get modded up, but it always astonishes me when people pine for the high-tech stuff while all along the ancient art would go a long way to solving the problem. architects and developers who neglect passive solar design principles infuriate me! it just seems so simple...

Check out the proposed SuperGrid - superconducting cables cooled by liquid hydrogen, which doubles as an energy storage medium.

http://access.ncsa.uiuc.edu/Stories/microbubbles/

Sometimes I wish the researchers would compare what tech there is already out there and see what other solutions have been tried and field tested. I was fascinated with human powered watercraft. So far the fastest craft are of the hydrofoil designs. Any craft with a hull in the water such as racing shells and other fast effecient designs are no match for the speed and affeciency of hydrofoils which either have no positive displacement hull (which sink if forward motion is lost) and those designs which lift the hull out of the water as forward speed increases. Human power hull out of the water craft can run in the 15-20 mile/hour range.

http://www.engr.uiuc.edu/communications/engineerin g_research/2002/AERO.summary.8.html#00.00.01.01.08 .01

The current listed record in the article is 23.4 miles/hour for a human powered craft. Racing shells with a team of rowers run slower. How much I don't know. I could't quickly find speed listings for shell racing teams.

at the height of the Arab oil embargo, exclaimed that there was "no energy shortage" and said that "at the current rate of consumption we have 600 years of oil left."

Fifteen years later, during the 1987 oil crisis, they ran a similar ad but this one said "at the current rate of consumption we have 200 years of oil left".

Amazing. In 15 years we lost 400 years worth of oil!!!

Both statements were right, of course, but what the oil companies were COUNTING on was that most folks would NOT understand that "at the current rate" doesn't mean that the rate wouldn't INCREASE. It seems that most folks STILL DON'T UNDERSTAND.

Now, we have politicians running for office with the promise that they will "replace oil fields with corn fields". To make matters worse, the US government is subsidizing corporations who make and run Ethanol plants, which immediately begs the question "If Ethanol is capable self-sustaining energy production sufficient to replace oil, why does it need subsidies?"

Independent studies by academic agricultural and environmental experts report that Ethanol requires an input of 54,725 BTU more for each gallon produced than you'd get by burning it. On the other hand, Ethanol industry sponsored studies claim Ethanol has a net energy of 17,058 BTU per gallon. Whose right?

Let's look at the problem in another way. Assuming pro-Ethanol groups are correct, how much Corn will it take to replace gasoline as a source of energy?

From http://www.farmdoc.uiuc.edu/marketing/grainoutlook /html/012306/012306.html we have the following facts:
1) The USDA's January estimate of the size of the 2005 U.S. Corn crop came in at 11.112 billion bushels.
2) Planted acreage of Corn in the U.S. in 2005 totaled 81.759 million acres, with a calculated yield of 135.9 bu/acre.

From Ethanol industry sources we find that the more efficient Ethanol plants can generate 2.68 gallons of Ethanol from each bushel of Corn. Therefore, 11.112 billion bushels of Corn can supply 30 billion gallons of Ethanol.

A fact of chemistry that economic theory cannot change is that Ethanol supplies 76,000 BTU/gallon and gasoline supplies 120,000 BTU/gallon. In other words, it takes 1.5789 gallons of Ethanol to replace the energy in 1 gallon of gasoline. That COULD mean that 30 billion gallons of Ethanol will replace 19 billions gallons of gasoline. But, in reality, Ethanol produced from Corn replaces even less. From a pro-Ethanol website, http://www.ethanol-gec.org/corn_eth.htm#concl:
"We conclude that the NEV of corn ethanol is positive when fertilizers are produced by modern processing plants, corn is converted in modern ethanol facilities, farmers achieve normal corn yields, and energy credits are allocated to coproducts. Our NEV estimate of 16,193 Btu/gal can be considered conservative, since it was derived using the replacement method for valuing coproducts, and it does not include energy credits for plants that sell carbon dioxide. Corn ethanol is energy efficient, as indicated by an energy ratio of 1.24, that is, for every Btu dedicated to producing ethanol, there is a 24-percent energy gain. Moreover, producing ethanol from domestic corn stocks achieves a net gain in a more desirable form of energy. Ethanol production utilizes abundant domestic energy supplies of coal and natural gas to convert corn into a premium liquid fuel that can replace petroleum imports by a factor of 7 to 1."

That "7 to 1" is 7 gallons of Ethanol are needed to replace 1 gallons of gasoline! Here is how it is figured: about 58,942 BTUs must be supplied from external energy sources for each gallon of Ethanol produced. To be self-sufficient Ethanol must return that energy, leaving only 17,058 BTU/gal available as excess energy. Or, dividing 120,000 by 17,058 shows that it will take 7.0348 gallons of Ethanol to replace eac

Yup, a cluster of PS2's running Linux.

This is all really cool stuff. I'll admit, I'm biased. I go to a school that competed in iGEM, I'm good friends with a student team member, and I work for one of the faculty members on our iGEM team. My school's team modified E. coli bacteria to solve the burnt pancake problem. It's essentially a biological computer, albeit extremely specialized.

My ultimate point is that you shouldn't dismiss this stuff as useless or without practical application. Understand that the technology is just in its infancy, and that with time, genetically engineered machines and their products will probably be more that we could ever guess now.

Actually that's what he HAS been doing. Multi-threaded OpenGL in Tiger. Rumored 2x speedup in WoW, more as we get more cores. NICE.

Good point, but if we're talking about the same problem (how many people do you have to get before it's likely that two share a birthday), then the number's only 23. Once you reach 40, then the probability of a birthday match is about 90%. More here.

Glitching because of overheating would be interesting, if true.

The PlayStation 2 cluster that we built at NCSA had 65 machines in a rack, tightly packed, with the fans of the machines at the front and the back of the shelves pointing at each other. They ran like that for on the order of 15 months, and I'm not aware of any heat related issues.

There goes my PS3 beowulf cluster idea!

You joke, but considering a PS2 cluster was made, a PS3 cluster isn't really out of the question, especially when considering how much power the Cell supposedly has. This news actually does put a damper on the PS3 cluster idea.

http://www.eecg.toronto.edu/~moshovos/ACA05/read/A kkary.1998.MICRO.pdf
http://www.crhc.uiuc.edu/~mfrank/pubs/Malik-2006-T R2208.pdf
ftp://ftp.cs.wisc.edu/sohi/papers/1995/isca.multis calar.pdf

This 80-core processor would probably also benefit from the is_computer_on_fire() syscall available on BeOS.

Who doesn't use bash?

I actually worked on the CM5 "thinking machine" supercomputer. The line in Mission Impossible when he says he want's a thinking machine laptop had me laughing out loud in the theater. People were turning and looking at me.

In case you don't know, the thinking machine was a HUGE system, I have had smaller apartments.

http://archive.ncsa.uiuc.edu/Cyberia/MetaComp/Imag es/CM5_lg.jpg

You may also remember this system being referenced in Jurassic Park.

I still have a mental image of Ving Rhames being crushed by his thinking machine laptop.