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Comment Re:We already had this sales pitch... (Score 1) 114

There are a few things wrong with your analysis. The first is that disk writes tend to be bursty for desktop users. You write a few hundred MBs (or a few GBs) and then drop down to an average of a few tens or hundreds of KBs per second. Spinning rust can easily keep up with the average write throughput of a typical user, it's the bursts that it has problems with. If you can buffer a few hundred MBs of writes, reorder them to reduce head movement, and then write them out behind the user, then you'll get much better performance. Obviously, this won't help for server workloads where you're I/O limited all of the time, but it will help a lot with desktop / laptop use.

The second is that one of the big bottlenecks for modern filesystems is the wait until data is safely in persistent storage. System RAM doesn't help here, because it goes away with power failure. To ensure consistency, you have to pause writing parts of an update until you've received confirmation that the previous part is written. In a conventional journaled FS, for example, you don't start writing the updates until you've confirmed that the journal has been committed to disk. With NV cache, you can get this confirmation practically instantly. If there's a power failure, then the drive just has to replay the transactions from NVRAM.

Comment Re:Online ? Authors never shopped in real life (Score 2) 178

I thought Waitrose delivered everywhere where they had a large store. Don't they deliver in your area?

For what it's worth, I've had under a dozen substitutions in five years of using Ocado (fewer than I got in any six month period with Tesco before that) and things always come with long shelf lives. They also have excellent customer support and will quickly fix anything that they get wrong.

Comment Re:Online ? Authors never shopped in real life (Score 4, Interesting) 178

Unfortunately groceries kind of suck online in the UK.

Seriously? Between the major supermarket chains and Ocado all providing online order / home delivery, none of them works for you? I'll admit, I gave up on Tesco repeatedly sending me things that were one day away from their use-by date, but there's a reasonable amount of competition.

Comment Re:It's not just shocking, it's stupid (Score 1) 178

You actually see this on Amazon, where a number of third-party sellers automatically set their prices by querying the Amazon price or the cheapest third-party price and undercutting it slightly. This sometimes leads to amusing effects where two third-party sellers are offering something for 10% less than the cheapest other seller and forget to set a minimum price.

Comment Re: Robots are good (Score 1) 268

Doesn't matter how essential the goods are. All that matters is that competition exists in the market. And if robots can make anything, competition is trivial - just buy some robots and sell the thing cheaper (but still at a profit) and completely displace the other guy.

For that matter, we've seen this curve before - for normal consumer goods, why not have your own manufacturing robots at home, and avoid the markup? There are a few good reasons, but only if the markup isn't too high.

Comment Re: Robots are good (Score 1) 268

Self-checkouts, for instance do not offer any savings to consumers that use them over using a checkout with a human teller, for instance.

The store saves on overall labor costs. Given how competitive grocery stores (usually) are, prices go down at least a little for all shoppers. This is an example where automation won't kill all the jobs any time soon, as many people like the human contact of the checker, and avoid the self-checkout. But one day maybe checkout-free stores (like Amazon is pioneering) will displace normal stores, due to lower price.

Supply is one variable. Delivered cost is another. Technology is mostly about the latter - technology is that which makes it cheaper to produce something.

Comment Re:CEO's now ... (Score 1) 268

The CEOs in Atlas Shrugged won their war by unionizing and going on strike.

More than that. Rand realized that a well-managed company could continue for a long time without its CEO, as the next tier down would be good leaders as well, so she had the striking CEOs actively destroy what they had built.

Comment Re:It has its uses (Score 1) 388

When functional programmers talk about state they're referring to mutable state. What you are describing is simply data.

That isn't a function, not in the mathematical sense.

Until functional programmers start speaking the same language as people in industry, we'll keep rolling our eyes and ignoring you.

Comment Re:Moderate usage okay (Score 1) 388

Just guessing what AC means, but assuming he's talking about Java, enum's in Java can take arbitrary values (they're just instances of a class, and so can have as much state as you'd like, including lambdas). It lets you do the equivalent of creating an interface with one method, and a class that implements that one method specifically for each enum, without all that clutter and boilerplate. But it's a bit hacky, and best kept to small, self-evident lambdas. Java-style enums, aka "class enums", let you avoid a lot of switching in general, since often you were just getting some constant value associated with each enum value.

Comment Re:Wrong question (Score 1) 388

"To understand recursion in programming, first we must discuss recursion in programming".

To understand recursion, first we must understand recursion, and then we must understand tail recursion.

To understand recursion, we must incrementally increase our understanding of primitive recursion.

Comment Re:It has its uses (Score 1) 388

None of that sounds right. Every heard of currying? There's no real difference between a lambda and an object full of state, beyond the syntax. Lambdas capture arbitrary state. (Plus, in real software, the results of some functions is often some measurement of some changing real-world thing.)

Comment Re:Cultural ethics won't allow work-free life (Score 1) 268

As long as the capital class continues to manipulate the tax code to fund government on the backs of wage earners,

Did you just feed Marx into a Markov chain generator (Marxof generator!)? Short-term capital gains and dividends are taxed the same as income. Long term gets a discount, which is a hack to account for the fact we don't inflation-adjust capital gains taxes (and a hack that of course favors the powerful - every bit of complexity in the tax system exists to favor the powerful, in any economic system).

The sensible course is to inflation-adjust capital gains, then tax them exactly as income, no distinction. So of course we'll never do that.

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