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Comment: Re:Switched double speed half capacity, realistic? (Score 2) 219

by dnavid (#47762759) Attached to: Seagate Ships First 8 Terabyte Hard Drive

Welp, seems my post was a bit misunderstood. I was actually thinking transfer rates. Say you have an 8TB drive with 6 platters - the option could be to pair up the platters and write alternate bytes to each, doubling sustained read and write.

It could also be an option to turn on when you start using the drive, and if it gets half-filled up, it should be possible to decouple them and get the full size.

The tendency for many consumers is to have an SSD boot drive and a platter storage drive - but that platter drive takes some time to fill up, why not double speed it until it's half full?

I'm not 100% certain, but I believe the problem is that the hard drive head assembly moves as a single unit, which means all of the heads for all the platters must move in unison. But the precision required to move the heads to the precise spot on the tracks where the data is recorded is such that it would be too difficult to design the heads in such a way that when one was over its track, all of the others would be *guaranteed* to be over their tracks on their respective platters. To do this you'd need to have the heads each on their own arms with their own voice coils to keep them all on track simultaneously. But that would add enough cost to the drive, it would be cheaper to just buy two half-capacity drives and stripe them yourself.

Basically, I think its possible, but not economically logical to make hard drives in a way that would allow for this kind of in-box striping. That's what RAID is for.

Comment: Re:multi-drive RV tolerance?? (Score 5, Informative) 219

by dnavid (#47762683) Attached to: Seagate Ships First 8 Terabyte Hard Drive

Rotational Vibration (RV) is the vibration the drive experiences from the platters rotating at high speed. When you put a bunch of drives in a cage, some interesting harmonics build up which can shorten the life span of the drives further. Enterprise grade hard drives are built to better withstand these vibrations, lessening the chance of failure. (At least that is what their literature says -- personally I'd mount the drives using grommets or something like what Rackspace uses [rubber bands I think?]).

Actually, multi-drive rotational vibration tolerance is a design feature whereby the drive is designed to be capable of withstanding and tolerating induced rotational vibrations from outside the drive. Enterprise drives are normally designed to minimize the vibrations they generate and induce into their surrounding chassis. But on top of that, being able to dampen vibrations induced from the outside and function optimally can significantly improve the performance of the drives. In enterprise environments where performance is important, disk drives can theoretically tolerate a lot of vibrations by simply temporarily ceasing reads and writes until their read/write heads get back into alignment. But those pauses force the drive to wait for at least a full rotation before they can try again to read the same blocks. If this happens frequently the performance of the drive can be significantly degraded even if the drive lifetime isn't impacted. Multi-drive RV tolerance is not just about surviving the vibrations, its also about being able to function optimally without having to degrade performance when in a (relatively) high vibration environment, as is often the case in large high-density drive enclosures.

Without this feature, you can sometimes find your 4000 IOPS spindle array delivering only 2000 IOPS at random times, and not know why.

Comment: Re:Global Warming? (Score 2) 269

by dnavid (#47751395) Attached to: Numerous Methane Leaks Found On Atlantic Sea Floor

interesting.... however the problem lies in the fact thats it is higher than they thought, meaning it COULD still be worse than they thought, meaning AGW MAY NOT be the doom and gloom some make it out to be. this little bit of information is not a gotcha moment, but it leads credence to the idea that we still have no idea

Scientists discover something new, which suggests they were wrong before, which means they could be completely wrong about everything. Just like when scientists discovered a new species of butterfly, proving we still have no idea if life exists on Earth.

Only for the subject of global warming can scientists discover a potentially new way in which climate change could accelerate over time due to man induced warming of the deep oceans, and that is used as evidence that maybe its not happening at all.

Comment: Re:Every week there's a new explanation of the hia (Score 1) 429

by dnavid (#47751309) Attached to: Cause of Global Warming 'Hiatus' Found Deep In the Atlantic

In the end, what this comes down to is whether we, as a society, should leave these kinds of decisions to government selected experts. You may be of the opinion that we should. But if you accuse people who disagree with you of being unscientific or corrupt, you have crossed a line.

I would also be perfectly happy with picking climatologists at random. The result would be about the same as picking physicists at random to decide whether gravity officially exists.

Comment: Re:so what is the problem? (Score 3, Interesting) 172

by dnavid (#47734861) Attached to: Google Wants To Test Driverless Cars In a Simulation

I'd flip it around. An automated car should be required to pass both a road test and a bevvy of simulated scenarios.

Certainly. But the question was whether automated testing should be considered sufficient. I think I would do my own flip-around. I think if Google wants to change the California law that requires road testing to make it so that simulation testing is sufficient, then I think Google should donate the simulator, and if an automated car passes the simulation but fails in the real world in a way real world testing would have uncovered but the simulator did not, Google should be held liable for all damages associated with that failure. Under that circumstance, I would be inclined to trust that Google's simulators are a sufficient match to reality to consider substituting simulation testing for road testing.

If Google doesn't want to subject itself to that criteria, then that's a tacit admission the simulation is not guaranteed to catch all the problems real world testing can catch, and I would consider their proposal to be invalid on its face.

Comment: Re:so what is the problem? (Score 4, Insightful) 172

by dnavid (#47733943) Attached to: Google Wants To Test Driverless Cars In a Simulation

Test in the fscking simulation and then test on the street. Win-win.

You don't need to ask for permission to test your car with simulations. You only have to ask for permission to replace real world testing with simulations. Personally, I'm not fond of replacing real world testing completely with simulations. The problem is that the point of testing software is to make sure the programmers have properly dealt with as many possible real world situations, and to reduce the likelihood the programmers haven't ignored an unexpected circumstance. Simulations can only test for what the simulation programmers have accounted for. Its substituting the system programmers' judgment for the simulation programmers' judgment. Its useful, but in my opinion insufficient.

Comment: Re:The real crime here (Score 1) 455

by dnavid (#47733515) Attached to: 33 Months In Prison For Recording a Movie In a Theater

And what benefit does jail time give the public? Jail time for non-violent offenders is the stupidest, most useless thing we could do with these people. There are all sorts of public services that are in dire need of manpower. A shit ton of community service as a punishment is far far far more useful than just incarcerating people. I find it astonishing how primitive and archaic peoples' thinking is when it comes to punishments for crimes. Just like we don't spank kids anymore because it's pointless and counterproductive, we should also stop "spanking" non-violent offenders but put them to good use instead.

So if I steal a hundred million dollars, the absolute worst case punishment I could receive in Anonymous Coward-ville is a billion years of community service? That's a better risk/reward ratio than any business opportunity I've ever been presented with. I'm in.

Comment: Re:Free market (Score 2) 256

by dnavid (#47733467) Attached to: When Customer Dissatisfaction Is a Tech Business Model

Don't worry guys, the free market fairy will take care of it.

The free market has taken care of it. Good customer service is expensive. Consumers have demonstrated that they are unwilling to pay additional money for good customer service. Successful companies have aborted customer service to keep prices low.

Something to keep in mind whenever someone says "the free market will take care of it." The free market doesn't solve problems. It "takes care of them."

Comment: Re:Every week there's a new explanation of the hia (Score 1) 429

by dnavid (#47733165) Attached to: Cause of Global Warming 'Hiatus' Found Deep In the Atlantic

I think a lot of people, even some actual scientists, do not understand the role of skepticism in Science. There's a difference between scientific skepticism and peanut gallery skepticism. Scientific skepticism is healthy.

Scientists can speculate and debate as much as they want whether it's getting warmer or colder. The issue with the global warming debate is the political demands to translate the science into specific actions, often by scientists who have no qualifications in economics or politics.

I believe climatologists have a better understanding of economics than economists or politicians have of climatology.

I think the people best in a position to think about this problem rationally tend to be actuaries; insurance professionals. Insurance professionals have to apply imperfect knowledge and incomplete risk models and make economic decisions within that environment all the time. They don't always get it right, but moreso than most they tend to balance the two on at least large scales on some rational basis. Insurance companies tend to believe that the odds of economic damage due to climate change are high enough to be financially material. In other words they are tending to bet it is happening, will get worse, and they have to budget for that eventuality.

That doesn't mean they are right or that Scientific judgment should rest with actuaries. It simply means if the argument is that unless Scientists are 100% certain, and even if they are, they shouldn't be telling people how to spend their money, that's actually true to an extent. But they do have the right to advocate no different than anyone else does, and that advocacy tends to be based on something other than political ideology. And the actual people whose jobs it is to actually try to understand the risks on a technical level and also the economics on a macro level aren't siding with the skeptics. So the skeptics can't argue that presuming climatologists are correct is not economically practical to people who have to think about money. Scientific consensus has been pretty broad for quite some time, but in the last five years I've seen a shift even in areas like the broader business community and the military that ignoring the real risks that global climate change will have significant negative impacts is foolhardy. They aren't betting it *will* happen, they are doing what risk managers do: they have assessed the risk that the scientists are *close enough* to being right that its worth acting on that risk.

So yeah, scientists should do Science and economists should do Economics, but what the rest of the world should be doing is risk management. By the time 100% certainty for all aspects of all elements of climatology arrives, it will be History. But its way past the point where practical people with unbiased objective outlooks should be considering risk management: reducing the risks where possible and planning for the risks where necessary. And even the cold blood bean counters are starting to do that in earnest now.

Comment: Re:Every week there's a new explanation of the hia (Score 1) 429

by dnavid (#47733069) Attached to: Cause of Global Warming 'Hiatus' Found Deep In the Atlantic

Regardless of the role of skepticism, everybody seems to be overlooking one key point: If this paper were to turn out to be correct, current climate models are useless and will need to be completely reworked. Well, maybe not completely. Some more than others. But it would contradict some of the fundamental assumptions of most of those models.

Actually, that's not true, or at least its an exaggeration. If this paper is correct, what it actually says is that most of the models out there may have been basically correct, but missing an important parameter: an additional heat sequester due to deep ocean currents. No model is perfect, and when modelling a system as large and complex as the Earth, you have to work hard to simplify what you can to make the model work at all, while not oversimplifying to the point of eliminating the validity of the model's results. And most climatologists have known for a long time that the largest blind spot in most climate models is the Earth's oceans. That's why this sort of research even happens in the first place.

Comment: Re:Every week there's a new explanation of the hia (Score 1) 429

by dnavid (#47733049) Attached to: Cause of Global Warming 'Hiatus' Found Deep In the Atlantic

A lot of people don't the difference between a scientific hypothesis and a scientific theory. These climate change models are just hypothesis in software form. We won't able to run experiments for these hypothesis in our lifetimes, and in turn they will never reach the level of a scientific theory in our lifetime.

There's an oversimplified version of the Scientific Method that says we start with a scientific hypothesis, which is a conjecture or a guess, then we run an experiment, the experiment either contradicts the hypothesis or confirms it, and after X number of confirming experiments the hypothesis becomes a Theory. In practice, its more complicated than that and the transition from a conjecture to a theory is not binary. The theory of anthropomorphic global climate change is a large set of interlocking and overlapping smaller theories combined. For example, the theory of the greenhouse effect is strongly confirmed: different gasses in the atmosphere affect the absorption and radiation of infrared radiation in different ways, affecting the amount of net heat energy trapped on the surface of the Earth and lost to space. That's pretty settled. We can't, of course, experiment with thousands of different planet's atmospheres to test that theory in the simplified way, but we can do experiments on smaller scales and correlate them with Earth's atmosphere and the atmospheric conditions of other planets we can observe.

We know the first order effect of increased CO2: it tends to trap more heat energy. But that doesn't automatically mean global temperatures have to rise. That's the natural presumption, but Earth's surface is a complex environment. More heat energy could cause more clouds to form, causing a negative feedback effect which tends to slow or halt increased temperatures by blocking radiation from reaching the surface. The oceans have a huge impact on energy distribution on the surface of the Earth, and can sequester heat energy for a very long time in principle.

However, the net result of all of these various conjectures and theories in the aggregate is that the most logical explanation for the observed increase in global surface temperatures over time is the increase in CO2 caused primarily by human activity. That statement is less a theory, and more of an explanation for all the other smaller theories that individually explain small parts of the whole.

The transition from scientific hypothesis or conjecture rests not just with how many experimental wins the conjecture accumulates, but also the degree to which the conjecture accurately makes useful predictions and the degree to which it synergizes and accommodates other more well confirmed theories. We're never going to be able to experiment with other universes in all likelihood, but that doesn't mean the Big Bang will always be a scientific conjecture. Philosophers might make that claim, but the Big Bang is considered a genuine scientific theory because it makes testable predictions that are not just confirmable, but very powerful and wide-reaching. There's no obvious reason why we should observe the nucleosynthetic proportions we see in the observable universe, and yet the Big Bang makes very specific predictions about how much helium we should see relative to hydrogen. If the Big Bang was wrong, the odds of it making such a prediction accurately are extremely low. At some point, its not luck but skill, and in the same way at some point scientists decide a conjecture can't be that lucky, and therefore must, to a high degree of probability, incorporate some fundamental truth about the universe. It might not be precisely right, but it can't be completely wrong.

Over three hundred years after Newton published Principia, the theory of Newtonian gravity has held up remarkably well. Einstein didn't completely overthrow Newton, and after centuries its highly unlikely anything will: it simply makes too many predictions that are always confirmed. What Einstein did was modify Newton's theory, and only in extreme cases Newton could not possibly have tested. But its important to note that we don't trust Newtonian gravity just because of an abstract Scientific Method scorecard. We trust it as a scientific theory for a more practical reason: it works, and in all but the most extreme cases it always does. We still plot spacecraft trajectories with Newtonian gravity, to extremely high degrees of precision. Even if we couldn't test the fundamentals of Newton's theory (we can), it would still be a Scientific Theory for that reason.

Comment: Re:Every week there's a new explanation of the hia (Score 5, Insightful) 429

by dnavid (#47725945) Attached to: Cause of Global Warming 'Hiatus' Found Deep In the Atlantic

Sweet, I can't wait for next week's alternate explanation!

Go ahead "consensus" troll mods - do your worst to bury every skeptic questioning sketchy science on this story. Then go look in the mirror and call yourself a rational scientist.

Science is about skepticism. Even climatologists that support the theory of man influenced climate change are constantly questioning the data, and looking at alternate conjectures. The very article referenced explicitly states that many of the theories that were presented to explain why global surface temperatures in the last decade did not track the apparent heat load global warming induced were inadequate, and the subject of further inquiry like the research cited. That's how Science works. But Science doesn't discover all the facts instantly and doesn't advance in convenient textbook chapters. It isn't skepticism that tries to characterize Science as just a bunch of random guesses, one after the other. That's just ignorance of Science. Science works by incremental and sometimes studdering progress forward. There are lots of things we know with certainty. We know carbon dioxide traps heat in Earth's lower atmosphere. We know human activities have dramatically increased the levels of CO2 in the atmosphere. The net result is an increased amount of heat absorbed by the Earth. What precisely happens to that heat in all of the complex thermal systems on Earth is still not well understood. But that doesn't mean the core principles are just random guesses. We're still discovering how 19th century chemistry works, but no one thinks that new chemistry discoveries mean chemistry is left-wing conspiracy.

The history of scientific progress looks no different for any other subject than it looks for 21st century climatology. Our understanding of gravity, of the germ theory of infectious disease, of quantum mechanics all followed similar discovery and learning curves. The only difference is that general relativity and Schroedinger's equation aren't subjects politicians can effectively argue about.

I think a lot of people, even some actual scientists, do not understand the role of skepticism in Science. There's a difference between scientific skepticism and peanut gallery skepticism. Scientific skepticism is healthy. When a scientist is skeptical of prevailing theories and conducts intellectually honest research aimed at probing that skepticism, that's always valuable. Science isn't a poll: if a scientific theory is correct, it will survive skeptical research. If its wrong, it will eventually be contradicted by the evidence. But when someone with no understanding of the facts or the research misinterprets the natural skepticism that is at the heart of scientific discovery by filtering it through their own "common sense" then they don't understand why science is successful overall, and really ought to shut up about it.

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