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Another gas bubbling through the water "knocks" the dissolved gasses out of the water. So the oxygen bubbles up out of the water, along with the argon.

I believe you can make a process noncacheable today, and maybe even disable branch prediction. This would totally shut down Spectre and Meltdown. You can disable SMT, and there's a whole host of other things you can do to isolate your "secure" process on an existing chip. Nobody has done these things because they like performance.

For most of what most people do on their computers most of the time, performance is fine without speculative execution or branch prediction

I think you underestimate the importance of branch prediction.

Where does the article suggest the water is wasted? It seems to focus on the savings in terms of reduced demand on the municipal water plant- rainwater doesn't need to be treated- and in terms of changed behavior:

once they got that rainwater harvesting system, the way they’re irrigating is completely different, and they’re paying a lot more attention to how they irrigate. It really changes behavior. Definitely people are more careful with how they use that rainwater than how they were using the potable water to irrigate beforehand.

It used to be illegal to do anything except direct the rainwater, e.g. direct a downspout into your flower garden. You are now allowed 2 55-gallon rain barrels.

The bummer is, even though you can now have rain barrels, it rains infrequently enough in Colorado that it's not terribly economical to buy 55-gallon rain barrels.

At $2.77 per 1,000 gallons from the utility, with infrequent rainfall it's pretty hard to ever recoup $176 for a 110 gallon system from BlueBarrelSystems. You're looking at 580 rains required to break even- while Denver, for example, sees only 40 days with "any measurable rainfall" a year.

That might be the cost of the water today, but history suggests that the price of water can fluctuate wildly. This is doubly true of the marginal cost beyond a certain baseline, which, again, fluctuates. Even without a drought or increase in regional population, you are vulnerable to (utility price, not CPI) inflation after ~5 years. The math for computing a break even period thus becomes squishy.

There are many people that place great value on being partially-off-the-grid, on (conspicuous) conservation, and enjoy DIY projects.

All good points, and certainly if you went entirely off-grid, avoiding a water tap fee is big savings. Though, 110 gallons isn't going to get you very far if you're totally off-grid.

The reason it's so fascinating though, is that because it is a many-variable optimization problem where 1) many of the variables conflict and 2) we haven't actually agreed on the desired optimum. In the end it still very much has a "you know it when you see it" quality, and nobody has come up with math that definitively says "yes this is" or "no this isn't".

Actually, it's maybe a little like spam filtering.

Geography still matters because your interests are entwined with where you live, at least so long as you continue to venture out the front door.

Most people's social lives are entirely virtual these days. The boundaries are getting fuzzier.

Yes, there will always be direct local interests like fire, police, emergency service, sewage, utility, etc districts, but those services all have natural boundaries themselves, and the political boundaries can and often do match there at city/county/township/x-district levels.

But the state and federal levels, at least in the US, seem increasingly divorced from geography (outside of the Cold Civil War between rural and urban economies/beliefs/interests). The weird shapes of current gerrymandered districts is only possible because the geography is so divorced from the governing. If the shape of most US congressional districts was the shape of fire or sewage districts there would be riots in the streets.

Reminds me of water rights. During droughts, huge campaigns against residential water use in California- meanwhile industrial agriculture consumes 80%+ of the water used in the state, and has no incentive to cut back.

The only one who can keep up the house is owner, but as you can see in this case they'll just choose to pocket the rent.

I don't think it's just a profit thing. If you're a small time landlord, it's probably incredibly expensive to retain a gardener/landscaper for such a tiny job. On the other hand, unless you live down the street it's awfully difficult to mow the grass every week, shovel the sidewalk after snow, water the plants, and so forth.

A small time landlord has no economies of scale for professional services, but doesn't make enough money to quit their day job either. (which would give them time to do all this themselves)

I think the big picture goal of reducing speeds is much more than putting up a different sign. There's a whole movement out there pushing for denser development, reduced car-driven-development, and streets that are truly lower speed, not simply highways rebranded with different signs.

Segregating types & speeds of traffic is still good though, especially dedicated trails for pedestrian and/or bike traffic.

Reducing speeds is a form of collision prevention, is it not? A typical car can just about stop on a dime at 15mph, and a pedestrian has more time to react.

There's a whole slew of other pedestrian-friendly street design that we could & should adopt as well, but that doesn't make speed any less of a valid approach.

Speed, in of itself, is not dangerous. What is more dangerous on highways is differential speed. i.e. if you're driving 60 mph when the traffic around you is doing 80 mph, you're the problem. Probably exponentially so if you're driving slowly in the "fast" lane. While rarely enforced, most states in the US have laws that require you to pull to the right if you're impeding traffic (usually defined as holding up +2 vehicles behind you) - even if you're doing the speed limit. Yet, these laws are rarely enforced, just like "No Trucks Left 2 Lanes" is never enforced in & around Chicago, despite being posted every mile or so on I 294.

I'd wager, also, that speed itself is rarely the direct cause of an accident. High speed, though, will make an accident more severe. My bet is that distracted driving is the #1 cause of accidents. On my daily 2-hour round trip on Chicagoland highways, I usually see 4-6 accidents each involving >2 cars. The shear amount of people I see on their phones is staggering. Hard to tell if it's social media or texting, but you can always tell because their head is staring at their lap, or they're holding their phones at the top of the steering wheel for all to see. I also see people with their phones mounted on their dashes watching movies or TV shows. Playing with your phone while driving is far more dangerous than paying attention & speeding.

>What is more dangerous on highways is differential speed.

That sounds like an extraordinary statement to me, by which I mean that you need to support it.

First, let me make a distinction between crashes where drivers lose control after the collision, either due to shock to the driver or damage to the car, and crashes where they don't. In the latter case, I agree with you; a freeway scrape where both cars can slow in a controlled manner is probably pretty safe. And you are more likely to have that sort of accident when you are going at similar speeds in the same direction. But it's not a certain thing;

Cars are complex systems, and designed to operate without colliding with other vehicles. Cars are also much more likely to lose control when they are operating closer to their speed design envelope.

However, in the case where either the car or the driver is incapable of continuing to control the vehicle, at that point the car continues to hit other things until it's stopped (and is often hit then by traffic that isn't stopped.) At that point, total speed matters a lot.

There is just a whole lot more energy involved when you are moving fast than when you are moving slowly, and when energy is dispersed in an uncontrolled manner near people, those people tend to get hurt.

Speed, in of itself, is not dangerous

Certainly! Falling from great height isn't dangerous either, you know.

"It's not the pace of life I mind, it's the sudden stop at the end."

As long as you safely slow down before you approach the ground, it's not.

Reducing speeds in some places makes sense, but in county roads out in the country, it just creates a reason for bottleneck, which clumps traffic together, making collisions more likely.

For example, a 4-lane road that I drive on to get to the city will usually have two cars in the front driving practically the same speed, and slower than the traffic behind them. To fix this situation, the car on the left should speed up and get over, so that traffic can flow around it and spread out. Unfortunately, there is so much educational focus and enforcement on speed limits that the driver on the left believes [s]he is driving correctly.

Naturally, a lone country road designed for speed is fine. It's when you've got a high speed road with lots of on-street parking and pedestrians right next to traffic, even house fronts, where you've got a major clash of functionalities and a safety problem.

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