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Comment Re:touchpad (Score 1) 80

I don't like 'drag lock' functions because then that makes more steps. You have to three finger click, and then drag, and then three finger click. Too many actions for one operation. With a mouse it is basically one action, hold button and move mouse.

With the Mac trackpad it is one action: Press with three fingers and drag.

Clicking with three fingers gives the Dictionary and Thesaurus :)

Comment Re:Your government at work (Score 1) 336

Just because they use it more doesn't make them more savvy. The burning video did them more harm than good.

I'm not sure what harm you think it caused them but it certainly helped them achieve their goals. It gained huge attention to their cause and doubtlessly encouraged many other people to join them. They want to fight the US so antagonising them is not harmful, so by their distorted morality it did them more good and no harm.

Comment Re:Deja vu all over again (Score 1) 112

I'm not seeking to prove a claim. It's just the way things are.


Accordingly a CPU with a real Huffman coded instruction set might be even better.

The additional cost of caching, decoding and branching with bit-aligned variable-length instructions would outweigh any benefit from reduced instruction fetch bandwidth. It would take more gates and more energy, which is why nobody does it. Talk to the people at Intel and ARM who know about this sort of thing, or look at the trends in instruction set design for high-performance CPUs and ask yourself why none of them have gone in this direction.

The exception to this is situations where code space is very tight or memory bandwidth is very low, which is true is some embedded environments but not in high performance systems.

I don't need to presume, I know that they removed some complex instructions because they made the hardware more complex and reduced performance.

Which contradicts the evidence of the vast majority of CPUs ever made, which is they get faster as you throw more gates at them.

More gates only make CPUs faster if they are doing useful work. Wasting gates on complex decode or complex instruction semantics reduces performance.

Comment Re:Deja vu all over again (Score 1) 112

there is a linear relationship between code density and the functional bandwidth of the instruction caching at every level.

Even if this were true (which it isn't), and even if you were right that CISC has twice the code density of RISC (which it doesn't), it would still be a long way short of proving your claim that CISC gives better performance than RISC.

I don't presume to understand why ARM do what they do.

I don't need to presume, I know that they removed some complex instructions because they made the hardware more complex and reduced performance.

Comment Re:Deja vu all over again (Score 1) 112

I don't know what the use case for ARM would be. They have less performance per thread, a smaller maximum system image and a few other downsides.

ARM servers should have lower power per operation, which is a critical factor for data centres. So far this theoretical advantage hasn't been fully realised, but neither has it been comprehensively disproved.

Comment Re:Deja vu all over again (Score 1) 112

The Huffman like encoding of CISC instructions is certainly more beneficial for performance than the benefits of a 'simpler' instruction format which take twice the instruction bandwidth to do the same thing.

This is far from certain. Most instruction sets are decoded into mutliple RISC-like instructions (uops) which are then executed. The advantage of having a more compact instruction set is balanced by the greater energy required to decode those instructions, so there is no clear winner either way.

If the benefits of CISC are so great, why did ARM remove complex instructions from their 64-bit architecture rather than adding new ones?

Comment Autonomous Early Braking (Score 1) 304

In the EU this is called Autonomous Early Braking and is effecively mandatory on all new cars (you don't get an NCAP rating without it). The argument, as others have explained, is not that this technology is foolproof but that the benefits outweigh the disadvantages.

I've no idea if EU cars will keep this feature in US models, but it would be great if we could use the same terminology on both sides of the Atlantic.

Comment Re:I won't notice (Score 1) 332

Resolution has always referred to the number of pixels available on the screen.

Resolution has multiple meanings, this one is a late arrival to the list. In the early days of Computer Graphics the term was used in the scientific sense that applies, for example, to telescopes.

I don't object to this new meaning, but it is simply not true to say that this is the only meaning of that word in the context of electronic displays.

Comment Re:Of course it's good for society (Score 1) 227

You mean the physician (not a scientist) who started the anti-vax movement?

Andrew Wakefield started the MMR controvesy by publishing a paper describing research that linked MMR to various negative outcomes. This clearly marks him out as a scientist not just a physician. This paper has since be shown to be both incorrect and fraudulent, so he was equally clearly an immoral person who used science to gain popularity.

As well as being pedantic I am also trying to make the serious point that scientists who become celebrities are not necessarily good scientists.

Comment Science and opinion (Score 1) 227

Scientist have political opinions too and they are just as entitled to express them as anyone else.

Indeed. But they are not entitled to present their opinions as science.

This is a very hard line to walk and it is easy to inadvertently add opinion to a scientific statement. For example, "Scientists are warning that infant mortality will fall significantly over the next 10 years" or "Scientists are warning that CO2 emissions will cause a rise in global temperatures". Both of these statements expression an opinion about a prediction rather than simply stating the prediction. Better to use neutral words to focus on the science not the opinion: "Scientists are predicting that infant mortality will fall significantly over the next 10 years" or "Scientists are predicting that CO2 emissions will cause a rise in global temperatures"

And, to be fair, these opinions are often added by the media in order to make the results more interesting.

Comment Re:How about ignoring it? (Score 1) 484

I can't believe anyone can be stupid enough to think cannabis is dangerous enough to merit criminalization.

What you can or cannot believe isn't important, the truth is that canabis can have a devastating effect on the developing teenage mind. Even if you don't consider that enough to warrant criminalization, that does not justify insulting those of us who do.

I wonder how you arrive at that "truth".

Simple, I saw it happen to someone close to me.

Even the arch-enemy of cannabis, Nora Volkow, head of NIDA, admits that they can't prove it because association is not causation.

Unfortunately you can't ethically perform the experiments that would prove this in the way that you would like. The fact is that a lot of medical evidence comes from looking at the results of long-term population studies which can show correlation but can never prove causation.

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