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Comment Stupid argument (Score 4, Informative) 441

It's hilarious watching people argue over a topic that has already been shown to be a non-issue. The EIA (US) and German statistics show that, in aggregate, wind-energy sources produce a relatively steady amount of power. Individual turbines and even whole wind farms might not be deterministic, but all the wind farms taken together... are.

-Matt

Comment Re:Uh, sure.. (Score 1) 359

BBEdit gets a fair amount of use as well. Some versions of xcode will even emulate BBEdit commands, if you set the right option. (And may have the option to directly substitute BBEdit as the main text editor.)

But I get your point: If you are writing in Obj-C, you are probably using xcode, because you are almost certainly developing for either Mac or iOS, and that is where you need to be.

Comment Re:huh (Score 1) 394

Efficiency is a big selling point in refrigerators; one of the first things people will look at. (And it will be posted very obviously on every one in the store.) Cable boxes... Not so much. I’m not sure what the big selling points on them are - probably how easily it is for the cable company to monitor their usage.

Electric water heaters are probably big users in houses that have them - but I'm not sure that's even a majority of houses in the USA; gas-powered heaters are common, and more efficient.

Comment Re:And the winners are... (Score 1) 164

And... that's it? What did SMART say? Did you actually wear the SSDs out as-per the wear indicator? Or did you hit a bug in the samsung controller before the wear-indicator maxed out?

To be fair, the precise situation you describe, particularly if you did not retune the RAID-6 setup or the mysql server, and if the server was fsync()ing on every transaction (instead of e.g. syncing on a fixed time-frame as postgres can be programmed to do)... that could result in el-cheapo samsungs not being able to do any write-combining and cause a 256:1 write-amplication of the data.

With proper tuning the write-amplication could easily be reduced to 4:1 and you would probably be able to run the server with SSDs. Maybe use Intel or Crucial though, and not Samsung. It isn't just the controller that matters... just using stock firmware doesn't really net you a good, robust SSD and there aren't too many real vendors who work on the firmware vs just OEM whatever was supplied with the controller. Intel is probably one of the better ones. They actually fix bugs, as does Crucial. Samsung... I dunno.

-Matt

Comment Re:IO pattern (Score 2) 164

Yes, but it's a well-known problem. Pretty much the only thing that will write inefficiently to a SSD (i.e. cause a huge amount of write amplification) is going to be a database whos records are updated (effectively) randomly. And that's pretty much it. Nearly all other access patterns through a modern filesystem will be relatively SSD-efficient. (keyword: modern filesystem).

In the past various issues could cause excessive write amplification. For example, filesystems in partitions that weren't 4K-aligned, filesystems using a too-small a block size, less efficient write-combining algorithms in earlier SSD firmwares. All of those issues, on a modern system, have basically been solved.

-Matt

Comment All still going (Score 1) 164

I have around 30 ranging from 40G to 512G, all of them are still intact including the original Intel 40G SSDs I bought way at the beginning of the SSD era. Nominal linux/bsd use cases, workstation-level paging, some modest-but-well-managed SSD-as-a-HDD-cache use cases. So far wearout rate is far lower than originally anticipated.

I'm not surprised that some people complain about wear-out problems, it depends heavily on the environment and use cases and people who are heavy users who are not cognizant of how they are using their SSDs could easily get into trouble.

For the typical consumer however, the SSD will easily outlast the machine. Even for a pro-sumer doing heavy video editing. Which, strangely enough, means that fewer PCs get sold because many consumers use failed or failing HDDs as an excuse to buy a new machine, and that is no longer the case if a SSD has been stuffed into it.

A more pertinent question is what the unpowered shelf-life for typical SSDs is. I don't know anyone who's done good tests (storing a SSD in a hot area unpowered to simulate a longer shelf time). Flash has historically been rated for 10-years data retention but as the technology gets better it should presumably be possible to retrieve the data after a long period on a freshly written (only a few erase cycles) SSD. HDDs which have been operational for a time have horrible unpowered shelf lives... a bit unclear why, but any HDD I've ever put on the shelf (for 6-12 months) that I try to put back into a machine will typically spin-up, but then fail within a few months after that.

-Matt

Comment Re:Progenitors? (Score 1) 686

Never played the game. Didn't even know the concept was discussed in it.

And, on a relative scale, yes it's not hard. It's certainly far easier than sending a ship to trade with someone that far away. In fact, nearly all of the problems of interstellar travel go away in this case - the basic fact is that not having to slow down when you get there (and not caring about the safety of any occupants in the vehicle) makes the issue massively easier. You don't have to worry about fuel, or shielding, or long-term biological maintenance. Just accelerate it up to speed and have a few final maneuvering thrusters on an automatic system.

Of course, if you are traveling around you've solved those problems, and can if you wish launch from within your target's solar system. Which makes targeting much easier, though you may give yourself away as you get the weapon up to speed.

On the other hand, hiding isn't as hard as you might think, especially if life (but not sentient life) is moderately common. Most of it even makes economic sense: Keep your transmissions low powered and focused so there isn't much leakage, and keep the atmosphere fairly clean. That will make it nearly impossible to tell an 'inhabited' system from a 'life-bearing' system from any distance.

Of course any aliens could be proactive and be striking at any life-bearing system, although that's a lot of wasted effort. Still, even then if we were to move into space-based colonies and asteroids we could hide fairly effectively. (Again, communication would be the biggest leaker, but economics and the square cubed law help the hider out.)

Comment Re:Progenitors? (Score 2) 686

Or maybe the universe is so competitive that anyone who announces their presence eats the bad end of a relativistic weapon.

This is a reasonable fear - and the problem is unless you are sure the universe isn't that competitive, it actually makes sense to assume it is. Because it's not hard to build a relativistic weapon your target would never see coming, and would wipe them out with one hit. (And we wouldn't see much evidence of them out there, even if they were fairly common - they look like any other floating rock, really.)

So the moment you announce yourself you could become a target for an unknown assailant who will kill you before you know they are there. Run the odds on whether you want to chance announcing yourself then, and realize everyone else who might be out there is doing the same...

Comment A little surprised. (Score 1) 249

Google must know by now how bad a light its broken permission system is putting on Android. I can't run half the android apps I want to run on any of my Android devices any more because of the permissions they want. And a lot of the ones that I intentionally do not upgrade no longer work. It's making my three android devices useless and almost worthless.

I'm flabbergasted that there are full-on idiots in the Google command chain who are unwilling to address such a severe and obvious problem. Truly flabbergasted. Has Google gone insane?

I've already stated but I will again... when the iPhone-6 comes out, I'll be moving over to it from my perfectly working but horribly insecure Motorola Razr. At least then I can browse my facebook account from my phone without it sucking up all the stuff I've tried so hard to keep partitioned off of it. As it stands now, I can't even run customized UIs on my Android because the g*d* program insists on advertising on my notifications screen, even though I bought the paid-for version.

At least with iOS I don't have to worry about all this in-the-face crap ruining the experience.

-Matt

Comment Re:$5k (Score 5, Insightful) 875

This. The sheriff said he'd rather have a more police-oriented armored vehicle for his SWAT team, but they cost $300,000, and this only cost $5,000. It's bigger, slower, and uses more gas, but it's cheaper overall. He's working within a budget and it's budget-effective.

The rest is window dressing and statements to appease the press.

Comment Re:Arbitrage (Score 1) 382

The spreads are smaller because of computerized trading, *NOT* because of HFT. HFT itself, verses normal computerized trading and non-HFT computer trading, is not going to have a big impact on the spread. In fact, HFT algorithms themselves do not really work all that well if there is any significant spread. They require volume to operate... no volume, no HFT.

-Matt

Comment Re:Frequent auctions (Score 1) 382

I think reality tends to trump thought experiments. I don't dislike the 1-second auction idea, I think it would work quite well. But I disagree that IEX's ability to stop the HFTs cold is a fluke that will disappear as their volume goes up. Their reasoning is sound and obvious and immediately solves the biggest problem that money managers have these days when trying to buy or sell large amounts of stock. I don't see how volume changes the equation at all.

Besides, his paper does not appear to say what you summarized at least in regards to IEX. It simply states that IEX is solving one aspect of the problem. It's pretty easy to argue that the piece they are solving is the biggest piece of the pie. Personally speaking, I don't care about the aspects of HFT which only involve standard arbitrage.

In terms of HFT... it was obviously fraudulent from the day it started beind used. The SEC should have acted immediately and didn't. Companies were spending hundreds of millions of dollars on infrastructure to get sub-millisecond transit improvements and they were lying to our faces talking about improving liquidity, magically, well in excess of the capital they actually had in play, when it was obvious that they were only exploiting flaws in the system.

It was a failure of the financial media as much as it was a failure of the SEC, but the SEC *should* have acted immediately and they didn't. And the result is a major loss of trust in the mechanisms of the stock market to the point where many retail investors who didn't understand the low scale of the fraud exited the market and stayed out of the market when they should have stayed in. I'm not going to make excuses for those people, I certainly wasn't scared away, but the general public deserves better than what the media and the government has handed to them over the last ~6 years.

-Matt

Comment Re:Maybe there is too much capital? (Score 1) 382

What, you mean pensions that companies are unable to make good on? Sounds to me like they SHOULD be eliminated.

And you forgot the single biggest reason why poor people stay poor. It's a four-letter word. D.E.B.T. #1 reason. Not 'Jim Crow' laws, regulatory capture (huh?), the destruction of unions, or anything else. You seem to have a chip on your shoulder yet you don't know the #1 reason for why poor people stay poor?

-Matt

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