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Comment Re:It doesn't offer free shipping (Score 1) 298

Is Amazon shipping more expensive in the US? I can't remember the last time I bought anything from Amazon that didn't come with free shipping. The only difference is that Prime gives you next day, whereas their super-saver free delivery gives you 3-5 days (typically closer to 3). I've found that if I need something very urgently then I will go into town and buy it - there are few situations where tomorrow is soon enough, but in a few days time is not.

Comment Re: But but there has been no inflation in 10 year (Score 3, Informative) 298

There are two things wrong with your post. The first is that the electricity cost just from the CPU is significantly higher than the value of the BitCoins created. The second is the assumption that there are a lot of spare cycles on EC2. The entire design of datacentres like this is to ensure that the computers are used efficiently by ensuring that there is always some job ready to run.

Comment Re:and the TSA exists because... (Score 4, Informative) 393

The point of the broken window fallacy is that it assumes that causing work to be done will not cause other work to go undone and it therefore ignores opportunity cost. The glass maker in the story will be employed making the glass to replace the window, which increases economic activity on the assumption that the glass blower would otherwise have had no work to do. The point of the story is to highlight the fact that this assumption is usually untrue. It is very often misused, however.

In particular, it does not apply when you're talking about subsidies / investment that is required to produce a demand that will cause economies of scale to lower prices to the degree that would increase real demand. If, rather than one window being broken, a few thousand were, then that might cause the glazier in the story to invest in machinery to produce glass in high volumes. Once all of the windows have been replaced, the glazier is still able to produce glass at significant volumes and lower costs, and so reduces his prices to stimulate demand. This then triggers the development of industries that depend on the cheap and ready availability of glass.

That's stretching the story a little bit, because the production of glass is very well understood and there are few changes in the process that are more than small incremental improvements. It is very different in a comparatively new field, for example the production of solar cells, where new processes regularly produce 50% better (more efficient, cheaper, etc.) technology. It would be true of microprocessors, if not for the fact that this market has already moved on to the stage where there is sufficient demand to drive investment without needing external priming.

The motivation is largely irrelevant. The broken window fallacy would apply to the TSA if the TSA is hiring people who would otherwise be employed doing something productive. It is, of course, not the only way in which the TSA costs the economy. On my last trip to the US, I spent a total of around two hours in queues for security theatre, which could have been time spent in the airport lounge working. The same is true of most business travellers.

Comment Re:rebranded? (Score 4, Insightful) 138

And this post highlights exactly why: when a trend that's been going on for decades across administrations from both major parties continues (or, worse, accelerates slightly), what happens? Half of Americans loudly blame the current incumbent, causing the other half to reflexively defend whatever this trend is.

Hint: Government is not like sports. Don't mindlessly support the Red Team or the Blue Team, they're supposed to stand for something.

Comment Re:Hmm (Score 1) 273

Small business users probably have it hardest. But the UK government is spending £200m/year on MS Office. Cut that in half, and now you have a budget of £100m/year to improve LibreOffice. There are a load of small UK companies that would love to take that money. The average salary for a software developer in the UK is £40K/year (less in places where the cost of living is low). Throw in overhead of 100% and that means that it will cost around £80K/year to employ one to work full time on LibreOffice. The UK government could pay companies to employ 125 software developers to add the features they need and fix the bugs that they hit. If they did this, then:
  1. They would be spending £100m less of taxpayers' money each year.
  2. The money that they spent would be going to people working in the UK and circulating in the local economy, not being sent directly to the USA.
  3. There result of the £100m/year spending would be available for public use, making it LibreOffice a more viable alternative for businesses every year.

It seems like an obvious choice to me. The pragmatic business choice isn't 'do we pay Microsoft or try to use a free alternative', it's 'do we get better value for money by paying Microsoft to provide whatever they decide to provide and hoping that it's what we need, or by taking an off-the-shelf open source product and paying for the customisations that we want?'

Comment Re:x86 IS efficient (Score 1) 168

AArch64 doesn't yet have a Thumb mode. Thumb and Thumb-2 were created by examining large numbers of binaries, determining the instructions that compilers most frequently used, and then generating an instruction encoding that makes the most common instructions 16 bytes long. This is not possible with AArch64 until there is a large corpus of code to analyse and there are relatively mature compilers. In contrast, a lot of the shorter x86 instructions were ones that were used on the original 8086 / 8088, and are no longer regularly emitted by compilers. The AArch64 instruction set, however, was designed as a compiler target and so does produce quite dense code without the compression scheme. For example, it has a single instruction that allow spilling a pair of registers to the stack, which compresses function prologs and epilogs quite considerably (not compared to the ARM store-multiple and load-multiple instructions, but these add a lot of microarchitectural complication to the pipeline, whereas the store-pair and load-pair instructions are trivial to implement).

Comment Re:x86 IS efficient (Score 1) 168

Yes, it is a slight problem with ARM. It's also a big problem on x86 - there are a large number of ways of interpreting a two-instruction sequence depending on where you start within the first instruction. ROP (and BOP) benefit a lot from this, unfortunately. There isn't really a good solution.

Comment Re:Despite it's name (Score 1) 168

The Pentium M is a good example of how Intel remains dominant. It takes about 5 years to bring a CPU to market, for any vendor. You start with an approximate transistor and power budget and an estimate of what the market will want in 5-7 years. You then start work. Hopefully, the process technology gets where you need it to be and the market does what you expect. With the Pentium 4, neither happened: they were expecting to get to 10GHz with a thermal envelope of around 60W and didn't, and the market started caring about power as laptops and dense servers became big markets. If AMD had made this mistake, it would have cost the company a huge amount. Intel's size means that they don't start just one processor design, they start ten, and gradually cull them as either it becomes clear that the market isn't doing what they expected or that their designs aren't working out. They typically have 2-3 that can be ready to go in under a year, which is how they were able to pull the Pentium-M out of a hat.

This is also why ARM's strategy has changed with ARMv8 (and, to a lesser extent, with the later ARMv7 designs). Previously, most ARM customers build chips that were an ARM design plus some customisation. This was fine for ARM's traditional markets, because they were predictable and ARM could happily succeed with a small set of designs that covered this space. With ARMv8, they intentionally delayed the launch of their own designs and worked with other manufacturers (nVidia, AMD, and so on) to produce completely in-house implementations. This makes the ARM ecosystem a lot more resilient, because individual manufacturers can aim for different niches and they can bring them all to market. And, because many of these companies make money from producing SoCs, if they don't have a CPU core that makes sense for the current market, they can license one from one of the other manufacturers and add their own things on the side.

Comment Re:x86 IS efficient (Score 4, Interesting) 168

Actually x86 IS efficient for for something completely different. The architecture itself is totally unimportant as deep inside it is yet another micro code translator and doesn't differ significantly from PPC or Sparc nowadays.

This is true, unless you care about power. The decoder in an x86 pipeline is more accurately termed a parser. The complexity of the x86 instruction set adds 1-3 pipeline stages relative to a simpler encoding. This is logic that has to be powered all of the time (except in Xeons, where they cache decoded micro-ops for tight loops and can power gate the decoder, reducing their pipeline to something more like a RISC processor, but only when running very small loops).

x86 short instructions allow for highly efficient memory usage and for a much, much, much higher Ops per Cycle.

It is more efficient than ARM. My tests with Thumb-2 found that IA32 and Thumb-2 code were about the same density, plus or minus 10%, with neither a clear winner. However, the Thumb-2 decoder is really trivial, whereas the IA32 decoder is horribly complex.

This is just that big of a deal that ARM has created a short command version of ARM opcodes just to close in. But then this instruction set is totally incompatible and also totally ignored.

Thumb-2 is now the default for any ARMv7 (Cortex-A8 and newer) compiler, because it always generates denser code than ARM mode and has no disadvantages. Everything else in your post is also wrong, but others have already added corrections to you there.

Comment Re:so what about all my old devices? (Score 1) 254

There are relatively new systems, 2 to 5 years old, that only did 802.11b

Really? My laptop from 2003 supported 11g and the one before it didn't have any built-in WiFi, but has an expansion card that does 11g. I do have an 11b PCI card somewhere, but it's from 2001. I don't remember seeing much 11b kit being sold after about 2004. Ten years is a very long time in computer equipment. Two years ago most new stuff came with 11n support. 11n was standardised in 2009, although firmware-upgradable stuff was shipping in 2007 based on the draft standard, so there are devices that are getting on for 7 years old now that support 11n.

Still, if you get rid of all those 802.11b devices, you still do not clear up the 2.4ghz bands. There are even older wireless phone handsets still in use (I have two).

Older wireless phones (DECT and even analogue stuff) that uses that band is just a source of interference, so only decreases the speed by lowering the signal to noise ratio. It doesn't connect to the network and block other devices from broadcasting in its timeslots, using a disproportionate amount of the available bandwidth by taking longer to transmit the same amount of data.

Comment Re:Success = happiness? (Score 1) 397

That's only a true dichotomy if you define success based on some external definition. If you define success as achieving the objectives that you you set yourself, then it is intimately linked to happiness. It's easy to be happy if you are not meeting the expectations of society, but much harder if you are not meeting your own expectations.

Comment Re:Give Us Opportunity, Not More Mouths to Feed (Score 1) 398

Silicon Valley had a purpose at first, but I can't figure out for the life of me why anyone would want to invest, today, in companies that are based in one of the most business-and-individual-unfriendly regions of the nation.

Because there are a lot of competent people there and these days people don't stay in the same job for a very long time. People circulate between companies quite a lot and it's easier to get people to move to a place for a job if they have the option of other jobs in the same area if it doesn't work out for them. If you create a company in the bay area, you can easily find people who are looking for a bit of a change to work for you. If you move to the bay area, you can easily find a lot of companies looking to hire competent people (and some who will settle for not-totally-incompetent people).

You need to develop a critical mass of demand for a particular skill set for this kind of environment to become self-sustaining and the more companies are there, the easier it becomes for others. It's somewhat counter-intuitive, but it's the same reason why you often see shops and restaurants selling similar things in clusters - both benefit from people who go to one in the knowledge that if it's full or out of stock of what they want they can go to one of the others.

Comment Re:This is a scam (Score 2) 399

From your link, the $71k salary is only for those with a doctorate and at the top of their relevant scale. I don't know anything about the area, but $71k is a pretty low starting salary for someone with a doctorate in most of the US. From your link, the maximum salary for someone with only one degree is $53.5k, and the starting salary is around $31k.

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