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Comment Re:We're almost at the end with current tech (Score 1) 114

We've been moving sideways for 10 years. In the 20 years before that, clock speeds were doubling every year or two. For the last 10, we've moved from a norm of single cores to a norm of 4 (or 2 + "Hyperthreads"), rotating hard drives to SSD, and specialized architectures to support HD video, but clock speed has been basically stagnant while the processors are getting fatter, more parallel, and not just in core count.

We hit a wall on MOSFET clock speeds way before we expected. Turns out that power consumption is quadratic, not linear, to clock speed. Once you get over 4GHz or so, it becomes a substantial problem, and getting over 5GHz is a real ordeal. There are ideas for non-FET transistors, but so far none has worked out.

10 years ago, Intel was hinting at a massively parallel future (80 core processor rumored in development at the time), they've been slow to deliver on that in terms of core count, but are making progress on other fronts - especially helping single cores perform faster without a faster clock.

Well, Intel was right. They just aren't CPUs, but GPUs. Even a bottom-end GPU will have 80 cores, the price/performance is pretty good all the way up to 1500 cores, and if you really want, you can get 4000-core cards. Those "cores" mean "ALUs", but even if you demand your cores have discrete schedulers, an R9 Fury has 64 compute units (scheduler + 64 ALUs), so 64 separate threads at once, each of which has massive SIMD power.

Comment Re:Everyone has to learn about it. (Score 2) 191

That's what PHP frameworks are for. The main thing I look for in a framework is actually just a good DB interface. One that simplifies query construction and automatically escapes data. I've written some surprisingly complex queries using CodeIgniter's Active Database system (Laravel has a very good one too). About the only time I have to write SQL by string concatenation is when I do crazy subselects or unions.

I don't know why that functionality is bound up with frameworks. I think it's because PHP's managers are trying to forge a simpler, elegant language out of it, reacting to the throw-it-in nature of early PHP, but they've gone overboard with both that, and contradict themselves by keeping broken functionality around for compatibility.

Comment Re:I agree with Trump (Score 2) 575

According to Thomas Aquinas, whose teachings are highly respected within at least the Catholic church, there are three types of law in the Old Testament: moral, judicial, and ceremonial. The moral laws are permanent, being the ethical foundation of the old and new laws. The judicial laws, though no longer binding, are no sin to follow, as they are built upon the moral laws. The ceremonial laws are forbidden, as to follow them would be to declare the old covenant still binding (this is why Catholics do not keep kosher).

All of the above quotes can be classified as either judicial or moral laws under Aquinas. You can also classify Deuteronomy 13:9 as judicial law - so modern Catholicism would not consider it a serious sin to stone apostates.

I'll let someone else explain the Orthodox or Protestant views on following the Old Testament. I'm even less an expert at those than I am Catholicism.

Comment Re:Annoying (Score 3, Insightful) 327

I thought this too, but after reading the article, it seems knowledge that red mercury is fake is already easily found. They just ignore it, often rationalizing the evidence of a hoax as a government-run disinformation campaign. They'll just think the same of the NYT's article - perhaps it will even egg them on, if the government is so desperate as to have their news puppets push this story (or so they'll phrase it).

Comment Re:20 cores DOES matter (Score 1) 167

It is a complicated subject. Some tasks do not benefit from HT - those whose memory access fits entirely within cache, and who make use of operations that cannot be spread among execution units in a core (or where the pattern of operations is superscalar with a single thread).

Simultaneous multithreading (the non-trademark name for HT) offers benefits in certain situations. First, where the memory access pattern is unpredictable and/or uncachable - it essentially lets one thread keep the core working while the other thread waits on the memory access (this breaks down when the task is purely memory-bound - it can actually hurt performance due to cache fighting). The second is when the two threads use different execution units - one is doing mainly compares and branches, while the other is crunching on floating-point. This puts more of the core to work at once. The third is when the two threads use the same execution units, but the core has multiple copies (a Haswell core has like three integer ALUs).

I'm not surprised it failed with computational chemistry. That's about as memory-bound a task as you can find. You probably would see 0% performance improvement from doubling your actual, physical cores, unless you upgraded the memory controller alongside it.

I cited the anecdotal averages I've seen. Some tasks saw 200% speedup at long ago as Nehalem. Others are actually hurt by HT even under Haswell. It's a complicated feature and the variance is substantial.

Comment Re:AMD's response? (Score 1) 167

49mm^2 is "massive"? A high-end processor is 500-600mm^2. And even if microfluidics works to remove heat (how do you have a layer with both enough fluid channels to cool, and enough TSVs for communication?), that will increase your cost substantially. I would expect $1K+ for a quad-core CPU under this kind of design.

Comment Re:AMD's response? (Score 5, Informative) 167

AMD has been developing a new microarchitecture, Zen, which will replace the horribly-designed Bulldozer. It's rumored to be made on a 14nm node, and they re-hired the guy who designed the K10 architecture (aka the last good CPUs AMD made), so I expect it to be reasonably competitive with Intel. I really hope it is, at least.

Your terminology is completely out of whack ("stacked single-die CrossFire GPU" is a phrase with more contradictions than whitespace characters), but I'll analyze what you were trying to say instead of what you actually said:
#1: Current chip-stacking tech doesn't allow for all that much bandwidth between chips, especially when going above two layers. CPU cores need a pretty hefty amount of bandwidth to their cache, so that's already problematic. Stacking dies also limits thermal performance - if you stack two dies, you have 2x the heat in 1x the heat-conducting surface area. For low-power stuff, that's fine, but CPU cores get pretty hot. Many high-performance dies are already performance-constrained by how much heat they can conduct to their cooler.
#2. This is a good idea. Or rather, the good idea is "APU on an interposer using HBM for main memory". You'd need bigger CPU caches - HBM is ridiculously high-latency even by VRAM standards, it will really hurt CPU performance otherwise. And it will limit upgradability - no way to just pop another DIMM of DDR3 in there. But the GPU gains should be worth it.
#3. Again, thermals will absolutely prevent you from stacking GPU dies. HBM and stacking doesn't do ANYTHING for the power efficiency of the chips you're stacking, so that's two 100W+ dies on top of each other. Not gonna happen. You could stack them side-by-side on an interposer, but at that point why not just fabricate them as one die?
#4. The cost of an interposer is significantly greater than that of a printed circuit board, and a lot of stuff won't benefit from the greater bandwidth to the CPU - stuff like a USB controller or audio chipset. Stacking the dies is also more expensive than just using a PCB - it's done in phones where space is REALLY constrained, but even the smallest desktops aren't that tight for space yet. So all that's left is putting everything onto one die - which runs into yield problems, because with bigger individual dies, a single defect will wipe out a lot more silicon. AMD actually *is* already doing this with their lowest-end laptop/desktop parts - look at Socket AM1, there's not much on the motherboard besides external connectors and power-delivery circuits. But they're also pretty low-end in performance.

Comment Re:For once I agree (Score 5, Informative) 267

Let's hope "video autoplay" is next!

about:config media.autoplay.enabled = false
There might be a UI method of getting to that but I couldn't find it in the five seconds I allocated to searching. Note this only stops HTML5 videos, but you really ought to have Flash set to click-to-enable (or disabled) for myriad other reasons.

Comment Only $240M? (Score 1) 226

Only $240M in funding? Last I checked, REL had specced the program as costing $12,000M.

This isn't even the first time they've gotten funding. They've gotten about $450M in several previous rounds. Did they pass some milestone to earn more funding or did they just get paid for the sake of not canceling the project? As far as I can tell the only component that's been tested is the intake air precooler.

Comment Re:Sigh (Score 2) 418

You are absolutely and completely incorrect.

A one-time pad is an encryption method using a key length as long as the plaintext, never reused. Trying every possible key for a given ciphertext will produce every possible plaintext - literally every possible message with that length.

Even if you knew part of the plaintext, that would only tell you part of the key, and no bit of the key is used for more than one bit of the ciphertext. It tells you nothing you don't already know. The only possible cryptanalysis of a one-time pad is finding a flaw in the means used to generate the key - if it is not truly random, attacks are possible. But properly-implemented one-time pads are literally unbreakable. Only their difficulty of use prevents them from being universally used.

Comment Re:so... (Score 1) 294

Is broadcasting propaganda even illegal? Sure,maybe ISIS propaganda would count as "inciting violence" but just repeating the official Chinese government lines doesn't exactly do that. We're not at war with them, and it's not "material aid", so it definitely doesn't count as treason. It's rather distasteful but I actually don't see a reason to ban it, if all they're doing is repeating Chinese lies. (Lying is, after all, not intrinsically illegal)

Really, it doesn't sound too different in kind than Radio Free Europe. The lies are perhaps more blatant but I don't doubt RFE has spouted pro-American bullshit.

Comment Re:Voice from that hot and wet hole. (Score 2) 80

Most minerals have intrinsic utility. Gold is useful as both a conductor and as a reflective coating. Silver is useful in various chemical compounds. Platinum and iridium are very useful catalysts.

A better comparison would have been to fiat currency, which is equally useless except as a means of economic exchange.

Theory is gray, but the golden tree of life is green. -- Goethe