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Comment Re:Is this guy a Mormon? (Score 1) 392

Large floods happen all the time. The story Atra-Hasis was probably based directly on a real flood or a version of an earlier story that was based on a real flood. That’s not the point. The Hebrews could have borrowed a different story and still incorporated the same message. The facts aren’t important; the philosophy is.

As for scientology, this makes me think of intelligent design. There is a historical chain of evidence that demonstrates clearly that ID evolved from Creationism after it was ruled unconstitutional to teach in science classes. ID proponents try to characterize ID as “scientific theory,” despite the fact that it makes no (or nearly no) testable claims. Really, it’s an attempt to use weasel language to make a fundamentally religious agenda appear as though it is scientific and brainwash school children into thinking that a negative argument (if you don’t yet have a naturalistic explanation for some minute detail. uh, I guess God must have done it [*]) can be considered an alternative to a solid scientific theory based on a huge body of evidence that makes mountains of testable claims.

Scientology is the complement of this idea. To the higher ups, Scientology is a BUSINESS designed to make money from ignorant people. They couch it in religious terms in order to get special legal treatment and make initiates think there must be some mystical truth in it. But even Hubbard referred to the rediculous mythology as a “space opera.” Like I said, self-parody.

[*] One of the main problems with ascribing unexplained phenomena to supernatural causes, in regards to being a scientific theory, is that while it may be an explanation (true or not, it is offered as an explanation), it’s definitely not a USEFUL explanation. One of the valuable functions of science is that it produces models of reality that have useful engineering application. With evolution, it has been useful in many kinds of research, such as medicine. We can rely on its claims to make predictions that guide successful experimentation and design. The problem with invoking a supernatural cause for anything is that engineers cannot do magic, so the ID explanation has no practical value. Even if it contained any truth (e.g. aliens have been tweaking our ancestors for billions of years), we need naturalistic explanations in order for humans to innovate. (BTW, you don’t have to see the engineering value in order for something to be a valuable scientific pursuit.)

Comment Is this guy a Mormon? (Score 1) 392

I’ll start by saying that I like Mormonism (from a distance) because every single Mormon I’ve met was really really nice. Although, “saccharine” comes to mind for some of them. I’ve read things by former mormons who complained that mental illness like depression is verboten in Mormonism such that you basically have to pretend to be really really happy all the time, even if you need medical treatment. But that’s probably a biased source. I applied to work at Brigham Young (among countless other schools), and I had to swear to never have coffee, tea, or other “hot drinks.” I looked this up, and their rules make absolutely no sense.

Anyhow, the summary makes it look like this guy really really likes Mormonism. Is he a mormon? He loves Android and elaborates on how hard-working and sober they are.

What’s interesting about Mormonism is its relatively recent history and what we know about it. WIth other religions, the “facts” are lost to history such that it’s very difficult to prove those details to be false. Not so with Mormonism, which developed in recorded history. Basically, watch the relevant South Park episode. It tells you everything you need to know.

That being said, the “facts” of a religion aren’t necessarily a deal-breaker. If someone claims the details of their scriptures to be historical fact, I roll my eyes. But if you take it as allegory, you can get good philosophy (and some bad philosophy) out. (Think of religious scriptures and traditions as a product of cultural natural selection, where sometimes some of the bad ideas have been filtered out over time.) For instance, ancient Hebrews had a disctinct pattern of taking someone else’s legends and modifying them heavily to add a moral message (whether or not we agree with the message). So, the Genesis flood story was a rewrite of the earlier story of Atra-Hasis. Other religions do this just as heavily. With Mormonism, I can let it go because it seems to be mostly beneficial, while Scientology (I hesitate to mention Scientology as a religion, because it’s really a Ponzi scheme, but they want to call it a religion) is evil and obviously a self-parody.

Comment Lying must be in their contract (Score 1) 291

A court can’t compel you to lie, but there’s nothing that says that your arrangement with the NSA can’t compel you to lie. It could very well be that RSA’s contract wiht the NSA states that if they are asked about this that they must categorically deny it.

What bugs me the most about this is that there isn’t any sort of grass-roots push to vote out congress representatives who have supported this unconstitutional spying. Of course, there are no guarantees about their replacements (all of which will really be selected by their political parties, not really the people). But this would (a) probably reduce the concentration of supporters of these laws, and (b) send a message that this garbage isn’t supported by the people. Eventually, repeated voting selection will, after many years, filter out politicians who advocate spying.

Comment The Power Wall isn’t about “green idio (Score 4, Informative) 267

It’s not about “green idiots.” It’s about the fact that chips will melt (burn? fry?) if you don’t keep them cool, and you can only dissipate so much heat from air cooling. Water cooling is used in HPC systems, but that too only goes so far. What’s next? Everyone needs a supply of liquid nitrogen to run their desktop PCs?

The “power wall” is a real, practical problem, which we reached somewhere around 2001, where power dissipation hit ~150 Watts in high-end systems. And the challenges go beyond cooling. Did you know that half the pins (around 1000) on a modern CPU are used just for power and ground? Do the math on trying to get 150 Watts at 1 Volt through a single pair if wires.

Oh, and what about mobile computers? Current battery technology can only old so much charge. Do you want your cell phone to get only an hour of useful life before recharging?

Comment Yeah, but Java is slow (if _I_ write it) (Score 1) 286

Paul Graham liked to blog about how awesome Lisp is. Apparently, he did some web back-ends in Lisp and was able to stay ahead of the competition. Now, Lisp has some awesome features. The two that stick out to me are (a) Lisp macros, which are arbitrary Lisp code run at compile time that emits arbitrary Lisp code that gets compiled, allowing some seriouly powerful constructs to be created very concisely and (b) massive libraries. That being said, I suspect that Paul Graham and his cohorts were more successful at using Lisp compared to another back-end language because they were both very skilled at the language and also super smart. The language they chose is actually MUCH less important. If they’d chosen another language, they would have done probably just about as well.

If you’re not a super smart programmer, I recommend Java (among other languages). Pass-by-reference and garbage collection obviate a lot of coding mistakes. And with Jit compilation, you get pretty darn fast code. Under 99% of circumstances Java performance is way better than adequate and makes MUCH better use of programmer engineering time.

But if what you want is super fast performance, a super smart C++ programmer will beat a super smart Java programmer. It’s a lot HARDER to get better results from C++, but the ceiling is higher. Some reasons for this:

- In memory-constrained environments, garbage collection imposes some overhead. I’ve worked on huge programs near the VM size limit whose performance was limited by GC performance. Most of the time, incremental GC in another thread is a win, but it can be a huge liability in memory constrainted environments. Instead, manual memory management in C++ allows you to make tighter use of the memory space and performs better in a memory-constranied environment.
- In a CPU-constrained environment, background GC steals cycles away from computation.
- Just like how macros are a huge win in Lisp, C++ templates generate customized code at compile time that can have huge perfrormance benefits. This is why C++ sort is faster than the C library qsort: The C++ sort is a template that inlines the comparison function for the type you’re sorting, rather than making a method call. In Java, you MIGHT get some of this from a fabulous JIT compiler.
- Compiling to bytecode is a huge information loss. If you used gcj to compile Java to native code, there’s the potential to have less information loss and therefore optimize better based on the programmer intent. But normally, Java uses bytecode as an intermediate. With more programmer intent knowledge, the C++ compiler can make smarter optimizations.

I could add more things, but I have other real work to do. Before I go, I’ll cap this off with two practical thoughts. You CAN get better performance from C++ than Java. Do you WANT to?

- Java has massive libraries too, where the critical parts are written in optimized native code, so if you make heavy use of Java libraries, you’ll see almost no difference in performance with regard to CPU throughput (GC being a separate issue). With no perceptible impact on peformance, less code to write, fewer common programming errors, and better use of engineering time, Java is quite often just an all-around practical win over C++. I say this as a programmer who prefers C++.
- If you’re REALLY REALLY concerned about performance, use Fortran. The language is more restrictive, providing the compiler with even more freedom to optimize. (For instance, no aliasing, no recursion.)

Comment Because HR people are nontechnical (Score 1) 465

Your resume is examined first by a totally nontechnical HR person. To them, the job position requires that you have 10 years of experience in Blurg and 5 in Blarg. They see 1000 resumes a week and therefore must filter them quickly by selecting checkboxes. There is no room whatsoever for fuzzy logic here. Either you list the skills and pass to the next round, or you don’t list the skills, and your resume gets thrown in the can. The technical people writing the job descriptions are often marginally technical themselves, so they don’t necessarily know if the combo of skills they compiled by committee is even reasonable.

And I don’t know a way around this. You simply cannot have all the technical people filtering the resumes. They have other work to do. I think at Google, the technical people get involved at a lower level of the process, and I get the impression it’s a burden.

Comment I won’t see the difference (Score 1) 271

We still have a lot of DVDs. When we put one in, I tend not to notice the resolution much, except that the bluray player makes the closed captions really blocky (cheap Samsung that doesn’t upconvert). Then when we put in a bluray, I DO noticed the difference, because of the added crispness and more vibrant colors. But on this 60” TV we have, I can’t imagine how I would see any finer resolution. The resolution and distance from the eye already make it so that there’s no way I can make out individual pixels. How would a higher res display make any perceptible difference?

Comment Finally, a crummy company actually goes down (Score 1) 182

So often, we see companies making shoddy products manage to continue to snow customer after customer. It’s finally nice to see one actually get what they deserve. Everything I’ve ever gotten from OCZ had some kind of major problem. The only thing worse than their products was their customer service.

Mind you, MSI wasn’t any better.

Comment Good multi-thread, bad single-thread (Score 1) 53

These processors are like an Intel version of Sun Niagara, but with wider vector. Actually, from an architectural perspective Xeon Phi (Larrabee) is pretty basic. They’re an array of 4-way SMT in-order dual-issue x86 processors, with 512-bit vector units. I think one of the major reasons Xeon Phi doesn’t compete well with GPUs on performance is that legacy x86 ISA translation engine taking up so much die area. Anyhow, so if you have a highly parallel algorithm, then Xeon Phi will be a boon for performance.

But as we know, there are numerous very important algorithms that are not parallelizable.

Comment Ender’s Game: Bloodbaths and monarchies (Score 2) 730

In the days of kings, someone would come to power typically because they were a powerful warrior. Indeed, in medieval Europe, the economy was based on a number of monarchs frequently going to battle with each other over land and resources. If you were a king of England, and you didn’t try to take over some part of France during your reign, you were a failure. (This explains the right of succession by blood. They didn’t know about DNA, but they did know that relatives had similarities and wanted people similar to successful past rulers.) Interestingly, the most successful monarchs were those who were loved by their own people (good management ability) feared by everyone else (mindless slaughter of people in foreign lands). This delicate balance between aggression and empathy was hard to find, and looking at the history of the English monarchy, not everyone managed it. This sounds like Ender’s game: In the history of the English monarchy (which I am a bit less ignorant of than others), there were plenty of Valentines and Peters those reigns ended in one kid of dismal failure or another, while the Enders are well-known in history. In the abstract, this sounds cool, except Ender and those successful kings were responsible for wide-spread slaughter of countless.

So this idea of returning to a monarchy sounds really bizarre to me. Rule by the one or few is not a recipe for peace, security, or freedom. In medieval Europe, if you were a peasant, you might live out your life unmolested, or you might fall victim to the whims of a foreign army or your own. Peasant life was essentially worthless except for the bit of farming they could do. This sort of attitude was the case into the 19th century. Have a look at the way the English treated the Irish when the potato blight killed off their only economical source of food. The Irish were under English rule, but apparently not under English protection, because all Parliament did was quibble while people starved to death. We also tried communism in several countries. The Soviet Union fell due to a collapsing economy, and China systematically converted to capitalism. Of course, capitalism is a system of economy, and China is still a dictatorship, but it’s a step in the right direction. Basically, when your life and your work have no value, then you have no motivation to work, except under the whip. So what these monarchists are suggesting is a return to slavery.

This isn’t the Christian fantasy of Jesus returning to earth to rule as a benevolent king. People will come to power because they want power, and then they will maintain that power by destroying others. We have that happening in our republics today. The differences are that (a) people are elected or not based on how their constituents perceive the representative to further their interests, (b) there are enough conflicting opinions that sometimes the bad ideas get filtered out, and (c) we have a judicial system that can find bad laws unconstitutional and overrule them. (Frankly, I think the executive branch in the US has too much power and is a vestige of the US legal system being a derivative of the English legal system, which has a figurehead king. We get to elect ours, but ours don’t seem to be very effective at anything other than being a scapegoat for the failures of the legislative branch.) Basically, a republic has problems, but a dictatorship is much much worse.

And let’s not forget to address the baloney about returning to traditional gender roles. As a society, we’re only beginning to respect individual human rights and dignity, regardless of ethnicity, sex, and sexual orientation. If we’re going to experiment with totalitarianism, why don’t we try putting some women in control? Oh, sure, they’ll screw it up too. Humans in power always do. But at least it won’t be a bloodbath.

Comment Speeding up the wrong algorithm again? (Score 4, Interesting) 32

I skimmed over the article, but I couldn’t tell: Is this another example of someone choosing an O(n^2) algorithm over an equivalent O(n log n) algorithm and then patting themselves on the back because they speed up the O(n^2) algorithm through parallelism, even though it’s still slower than the O(n log n) on a single processor?

I can’t tell because they go on about NFA’s, which would be exponential in time compared to DFA’s. That’s a totally different thing.

Comment A lot of supercomputing motivated by bad science! (Score 3, Interesting) 118

There are plenty of algorithms that benefit from supercomputers. But it turns out that a lot of the justification for funding super computer research has been based on bad math. Check out this paper:

http://www.cs.binghamton.edu/~pmadden/pubs/dispelling-ieeedt-2013.pdf

It turns out that a lot of money has been spent to fund supercomputing research, but the researchers receiving that money were demonstrating the need for this research based on the wrong algorithms. This paper points out several highly parallelizable O(n-squared) algorithms that researchers have used. It seems that these people lack an understanding of basic computational complexity, because there are O(n log n) approaches to the same problems that can run much more quickly, using a lot less energy, on a single-processor desktop computer. But they’re not sexy because they’re not parallelizable.

Perhaps some honest mistakes have been made, it trends towards dishonestly as long as these researchers continue to use provably wrong methods.

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