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User: ultranova

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  1. Re:The funny thing is... on Ext4 Data Losses Explained, Worked Around · · Score: 1

    They do.

    The other ones that force syncs from within the FS code every X seconds just have a very short X second window during which it can happen.

    No. The issue isn't how long writes to filesystem are delayed. The issue is that Ext4 allows writes to metadata happen before writes to actual file contents. All you have to do to fix this is ensure that a rename() will only be committed after any changes to file contents which preceded it. Do that, and there will not be any window, no matter how rarely syncs are forced.

    The ext4 FS code happens to allow a very long window for implicit synchronization because it allows great performance and any application compliant with the spec is already explicitly asking for a sync when they really need one.

    Forcing every application to call fsync() when all they need is to ensure that the file is either updated or left alone, rather than simply truncated to zero size as Ext4 might do, will lead to the very antithesis of great performance.

    This is an Ext4 bug, plain and simple. Ext4 follows POSIX, but POSIX never took recovering from crashes into account, so it is incomplete in this regard.

  2. Re:Bad POSIX on Ext4 Data Losses Explained, Worked Around · · Score: 1

    If that is true, then to the extent that is true, POSIX is "broken". Related changes to a file system really need to take place in an orderly way.

    In other words, we need a transactional API to the filesystem, one which guarantees atomicity of an entire transaction. It's not going to happen, of course, and we'll have to keep on relying on hacks, but it would sure be nice.

  3. Re:Workaround is disaster for laptops on Ext4 Data Losses Explained, Worked Around · · Score: 1

    Real solution is more like VIM:

    Doesn't work. You need another fsync() call between fclose() and rename(). Otherwise you're vulnerable to this exact bug; your system could crash after the rename() has been committed but before the file contents have been written, leaving you with an empty file.

    Your code snippet is exactly how the apps do it now (except no fsync(), since retaining the old file is acceptable), and it doesn't work in Ext4.

    Making the OS decide which data needs to be fsync'd when is just silly.

    This issue has to do with how writes to the disk are ordered relative to each other, not when they are done. The guarantee Ext3 makes (and Ext4 currently doesn't) is that file contents get written before metadata.

  4. Re:No kidding on Ext4 Data Losses Explained, Worked Around · · Score: 1

    The real problem here is that application developers were relying on a hack that happened to work on ext3, but not everywhere else.

    The problem is that there is no way which will work everywhere, except fsync - and guess what fsync does to performance?

    POSIX API needs to be expanded to include support for transactions. Until it's done, expect people to rely on hacks, because they have nothing else to rely on.

    No, that's actually precisely what the spec says, with one exception: You can guarantee it to be written to disk by calling fsync.

    But the application doesn't need that guarantee. It simply needs the guarantee that either the file is updated or left alone. It doesn't need to ensure that the file is indeed written; it simply needs to ensure that after a crash it either gets the intact old version or intact new version.

    In fact this is such an useful guarantee that PostgreSQL recently added a similar connection setting, "synchronous_commit", which can be set to false to retain most of the advantages of transactions - visibility and atomicity guarantees - but give up the guarantee that the transaction has been logged into the permanent storage when "commit" command returns.

  5. Re:LOL: Bug Report on Ext4 Data Losses Explained, Worked Around · · Score: 4, Insightful

    Solution: an update to the code to behave as idiot application programmers require with a simple mount option.

    The application programmers aren't at fault here, the POSIX spec is. A filesystem is essentially a hierarchical database, yet POSIX doesn't include a way to make atomic updates to it. The only tool provided is fsync, which kills performance if used. And even with fsync some things - such as rewriting a configuration file - are either outright impossible or complex and fragile.

    The real solution is to come up with a transactional API for filesystem. Until that's done, problems like this will persist. Calling fsync - which forces a disk write - or playing around with temporary files isn't reasonable when all you want to do is make sure that the file will be updated properly or left alone.

    The alternative is to have every program call fsync constantly, which not only kills performance, but ironically enough also negates some of Ext4's advantages, such as delayed block allocation, since it essentially disables write caching. And it doesn't work if you are doing more complex things, such as, say, mass renaming files in a directory; you have no way of ensuring that either they are all renamed, or none are.

  6. Re:Also, like the virtualization scare on Intel CPU Privilege Escalation Exploit · · Score: 2, Insightful

    You want to fool me, you have to virtualize my GTX 280.

    Why? VMWare needs to virtualize the hardware because it can't give the VM exclusive access to real hardware; but an SMM rootkit can. You can let the OS access the hardware directly to its heart's content, you're simply interested in controlling some memory locations - say, listening to keyboard and occasionally sending some network packets, or perhaps starting a process in the OS.

  7. Re:No, no, no on Shell Ditches Wind, Solar, and Hydro · · Score: 1

    In other words the plant would only need to sit there for maybe 100 years before it could be decommissioned and recycled. We already build structures that are designed to be maintained for over 100 years so this is well within our current capabilities.

    Build the reactors underground and when it is time to decommission them, just pour concrete down the chute.

  8. Re:No, no, no on Shell Ditches Wind, Solar, and Hydro · · Score: 1

    what makes people think they're going to bother to jump when the hurdles are removed?

    Competitors.

    Competition means that they'll cut safety features out of the design to make it cheaper. And quality workmanship also costs.

    Do you dig in various banks balance sheets before you create a checking account?

    No. But then again I live in a country where banks are heavily regulated.

    Now, how much research do you do when you're buying a five grand flat screen TV? Do you just buy the first hunk of crap with the fancy ad?

    I would never put five thousand dollars into a television. I wouldn't put that much into any entertainment.

    So, if average consumers are so careful to buy an appliance, what makes you think that purchasers of 500 million dollar reactors would suddenly act like brain-dead retards?

    Modern applicances are crap. They are crap because cheap crap sells over more expensive quality stuff. Crap breaks down quickly, and likely costs more in the long run, but it's cheaper at the moment of purchase, so it oversells non-crap.

  9. Re:It's fusion or bust on Shell Ditches Wind, Solar, and Hydro · · Score: 1

    Solar panels are JUST NOW starting to break their 1$/watt barrier. If we DOUBLED solar power usage every year for the next 20 years we would end up getting something like 10% of our power from solar sources. Think about that. AND that assumes having enough silicon for all those solar cells (there isn't enough. It's incredibly resource intensive to acquire silicon).

    Solar panels are for small-scale power production. For large-scale power station, you use thermal solar: use mirrors to concentrate sunlight into a tank of water, it begins to boil, you use it to drive a turbine. Other forms of heat engine can also be used; since you can get the temperature very high (theoretical maximum is Sun's surface temperature, around 5000K), they will be very efficient.

    The main problem with thermal solar (and all solar) is that it only produces power during the day (duh!); however, if you store the heat - in, say, a huge slab of rock - you could theoretically keep producing during the night.

  10. Re:Corporate culture on Shell Ditches Wind, Solar, and Hydro · · Score: 1

    Telling indeed. You're advocating a reduction in lifestyle, logically leading to de-industrialization.

    Yeah. It's like telling someone who weights 200kg to cut down on the chips, logically leading to them starving to death.

  11. Re:Corporate culture on Shell Ditches Wind, Solar, and Hydro · · Score: 4, Interesting

    The political and socioeconomic development of most third-world nations was ruined by Western powers dating back to the colonial era, carrying through neo-colonialism and the Cold War.

    You know, I live in Finland, which was first Sweden's and then Russia's colony until 1917, underwent a devastating civil war right after gaining independence, and was attacked by the Soviet Union twice in World War II, and had to resettle 400,000 people and pay $300,000,000 in war preparations. And yet, after all this, we're somehow overproducing relative to our needs, despite the fact that the country sits on the Arctic Circle rather than at the equator.

    At some point blaming some long-ago event for your problems becomes ridiculous. African countries have been independent for decades now, and even the Cold War ended over a decade ago; if they remain hellholes incapable of feeding their own population, the blame now rests on said population.

    "Our forefathers were oppressed so we must keep on killing our farmers or at least stealing their land." Victim complex at its finest. Besides, Africa seems to be the only former colony to be having this problem...

  12. Re:Corporate culture on Shell Ditches Wind, Solar, and Hydro · · Score: 4, Insightful

    Legally != scientifically. We're preaching to a geek group, which insists on the most factual representation of its topics (most of the time). CO2 is a fertiliser, whether the Supreme Court has seen fit to accept it as such or not. It helps plants grow, thus it definitively is a fertiliser.

    As it happens, one of the biggest sources of pollution for waterways is fertilizer. It gets washed from the fields into the water, where it promotes the growth of algae, turning a lake into a stinking pit. And the same happens in coastal areas where ever the conditions don't disperse it fast enough.

    Your argument seems to be that something can't be both a fertilizer and a pollutant, which is wrong.

  13. Re:Wait, what? on How To Get High-Schoolers Involved In Real Science? · · Score: 1

    You want to get students interested in "real science", then as your examples you cite some computer programs? And they learn what from this?

    Overtime is no longer exceptional but rather a regular and required component to get a decent (w/gr)age. Of course, to really make this similar to the marketplace, you shouldn't give extra credit but rather simply fail/fire anyone who doesn't participate.

    Seriously, the whole article was posted by some shithead on a power trip, trying to use his position of petty power to advance his personal goals. There's no reason why you should get extra credit for helping the teacher's pet project; and since grading is relative - you get graded relative to others - anyone who doesn't do it will have their grade lowered, making this blackmail. It's abuse of power, plain and simple.

  14. Re:Interesting thought on Believable Stupidity In Game AI · · Score: 1

    We are inaccurate, we jump to conclusions, we get excited, or calculate one branch of the tree very deeply while ignoring another one. Those types of things are tough for computers to do.

    Actually, wouldn't it be a very easy thing for the computer to do? Calculate the immediate consequences of a move, and then, if you check the opponent's king or eat a piece or some other heuristic determines this to be a good move, start calculating further down on that branch and ignore the further consequences of all others. That should model the human tendency to get overexcited and forget to protect his back quite accurately.

  15. Re:Best Road Safety Feature... on Auto Safety Tech May Encourage Dangerous Driving · · Score: 1

    If you're on a rural two-lane road, and someone wants to go faster than you, get the fuck out of their way.

    How about you, the guy who wants to go faster, finds a safe place to pass instead and maintain a safe distance until then? Or do you perhaps think that other people should go out of their way to fulfil your whims?

    I live on one such road and people like you who think they are the ultimate arbiters of traffic speed are stupid fuckheads who should all drive off the road and into a tree and die.

    You make a fine example of why a driver's license should include a mandatory psychiatric examination.

    Seriously. You want someone dead because they don't pull over when they see you in their rear mirrors? That's gotta be some kind of record in psychopathy. I hope you lose your license and car before losing control and killing someone for the horrible crime of thinking they have a right to drive on a public road unharassed. Seek help, you sick fuck.

    If someone is behind me and wants to go faster, I pull over and let them go by. We call this the golden rule - I would appreciate it if someone else would do this for me, so I do this for them.

    But I guess the golden rule no longer applies when you want to go faster, so it's okay to endanger someone else's life, eh?

  16. Re:It's just Good Business on Office Depot Employee — "We Changed Prices Too" · · Score: 1

    This sort of thing usually gets the scum in the end though. You can screw someone once on a sale, and make more money than you deserved, but to succeed with it forever you have to make sure the customer never knows he got jobbed.

    Which is hard to do, especially when such crap is being done at the level Office Depot is, it will get out. All it takes is one disgruntled employee.

    But by the time it does, the management has already cashed in their bonuses and gotten another job in whatever store the ex-customer tries next.

  17. Re:It's just Good Business on Office Depot Employee — "We Changed Prices Too" · · Score: 1

    I don't condone deception or fraud, but it's this prioritization of the lowest price above all else that brings these things about.

    With jobs leaving to China and the remainders wages going down, there really isn't much of an alternative. $50 is quite a few hours of work for most of the population. But hey, that's the blessings of globalization for you.

  18. Re:Oh great, there goes slashdot on Wikileaks Pages Added To Australian Internet Blacklist · · Score: 1

    If this were happening in Canada, I'd start publishing every link I could on every website I could, and ask (no, beg) for trial date, and with a jury.

    And once the prosecutor shows that your links link to websites which link to websites which link to websites which link to websites which contain child porn and terrorism, that jury will send you to the jail for life to the thundering applause of the crowd. After all, it's for the children.

    Your naivete is touching. It's also extremely foolish in the real world where a jury is made of concerned mothers and overprotective fathers. Don't try it; you'll accomplish nothing except destroying your own life.

    Remember, in a democracy the people have exactly the kind of government they deserve, and think what kind of scum must they be to deserve these.

  19. Re:Best Road Safety Feature... on Auto Safety Tech May Encourage Dangerous Driving · · Score: 1

    Compulsory big spike in the middle of the steering wheel.

    Move it to the rear bumbler and you've got yourself a deal.

    I've never, ever understood why some morons insist on driving half a meter behind me, even on otherwise empty roads. The so-called "professional drivers" are the worst of this lot, especially if they're driving a truck or a bus that's guaranteed to not stop as fast as me. Are they simply bloodthirsty, or is there some kind of rational reason for it?

    There's a device in these vehicles that keeps records of the speed they've been going. We need to add a radar which keeps track of the distance between a truck and the car on front; if the distance is consistently less than 20 meters - which is far too close in almost any situation, BTW - it should be grounds for compulsory and permanent loss of driving license.

    Cue a hundred butthurt truck drivers posting that they are professionals and know what they're doing. And of course they do: they're deliberately and in cold blood endangering my life to shave a half a second off of a few hours journey, since that makes them half a penny more.

  20. Re:Noooooo! on Brain Decline Begins At Age 27 · · Score: 2, Interesting

    As a 42 yr old college student let me be the first to say; Noooooooooooooooooooooooooooooooooooooooo!

    What's the point of going to college at 40? Does it actually increase your employability?

  21. Re:Tweet? on Juror Tweets Could Create Mistrial · · Score: 1

    I find the term annoying myself. I'd have a lot easier time taking the thing seriously if it had a name like SMS-over-IP. If I pitched it as a campaign avenue to my 60 year old boss, I'd get a response something like "If we're going to send our customers "tweets", we might as well go all out and send them fart blossoms or some other made up nonsense."

    So what you're saying is that a silly name protects a service from spam? Thanks, that's an important consideration when deploying new ones.

  22. Re:Dr. House Syndrome on Are Quirky Developers Brilliant Or Dangerous? · · Score: 1

    You can't measure the true genius coder (which I don't claim myself as, but I've known one) in terms of "x times more productive". They don't (just) churn out code faster, they solve problems in ways no one else would ever even consider.

    That's nice. Do these solutions consistently perform over 160 times better than the solutions made by average programmers? Because unless they do, firing the asshole is still the correct move.

    The thing is, we're talking about justifying keeping an abhorrent human being on staff. Someone who's making everyone else suffer, and thus less productive. The only justification, from a business point of view, is if that evil genius is worth more than the total worth of productivity lost by everyone else. And that pretty much requires comparing his productivity with theirs.

    And then there's the consideration that, being a psychopathic asshole, he certainly wouldn't feel any bangs of conscience selling your trade secrets to your competitors...

    Einstein didn't do math "faster" than Maxwell, he made a massive jump in reasoning that made the idea of the "aether" or even a rest frame completely irrelevant.

    Einstein was a scientist, while a coder is an engineer. Sure, an engineer might come up with a new type of bridge; but unless that makes the company more money, why should that engineer be preferred over any other?

  23. Re:Artificial scarcity on Linux Gaining Strength In Downturn · · Score: 1

    It's the ideal of communism, in which I take your cow but you still have your cow

    The ideal of communism is that whoever owns the cow also milks it and gets to keep the milk, rather than having to deliver it to some rich cow-owner who gives him a single drop in return, which is commonly known as capitalism - which might actually be beneficial for the milker if the huge number of cows bought and maintained in a single place by the capitalist allows the worker to increase his milking efficiency to the point where a single drop per cow sum up to more than what the single cow he could afford on his own could produce.

    Trickle-down economics, on the other hand, mean that the cow-owner drinks the milk and pisses on the mouth of the milker while reading passages from Atlas Shrugged. Again, this might be a beneficial arrangement for the milker if he is deaf ;).

    Anyway, the grandparent is either a troll, a Microsoft astroturfer, or an armchair economist who doesn't understand the Broken Window Fallacy. This last variant has actually sometimes gotten their voices heard even in dead-wood economist magazines.

  24. Re:Dr. House Syndrome on Are Quirky Developers Brilliant Or Dangerous? · · Score: 3, Insightful

    Genius developers who can solve problems in an hour which could take the rest of your team a month or more should get the same cubicles and be subject to the same strictures as everyone else.

    Genius developers like that should be employed as designers, not coders. By the time you start writing code, there should be no problems left that take even an afternoon, much less a month, to solve. Besides, to put it bluntly, I sincerely doubt you are more than 160 times more productive than an average developer. Finally, dunno about the article, but the summary didn't talk about someone getting rewarded, it talked about someone going out of his way to be an asshole; and that should never be tolerated, since it will lower everyone's productivity.

    If your genius developer doesn't document his code, a lesser developer can document it in far less time it would take any number of lesser developers to write and document it, or at least one of them isn't worth his salt.

    Except it's more difficult to understand someone else's code than to write it in the first place. This is especially true if the code is "brillant" - meaning it has hacks and abuse of language features that make strong men cry - and even more so if it's actually brilliant, since that means it uses concepts and solutions the lesser developer could never even imagine.

    The smarter the original developer is, the more important it is that he properly documents his code, since it's less likely that your average coder will understand the underlaying idea and be able to produce meaningful documentation.

  25. Re:Perhaps on Are Quirky Developers Brilliant Or Dangerous? · · Score: 5, Insightful

    It's not necessarily "enabling". I've known a lot of people who are just eccentric but incredibly bright (and have been told I'm one, which surprises the hell out of me), and it's probably just part of the territory.

    A guy who mutters to himself while working is eccentric. A guy who insults his co-workers is an asshole. And a guy who smirks while informing others that documentation doesn't exist is just plain malicious.

    Assholes should be kicked out of any team, because no matter how bright they are, they won't be able to compensate for the lowered productivity of everyone else who has to waste their time and energy to deal with their little power games. As an added bonus, it makes every other employee happy, thus making the world a bit better place. Profitable and morally right, firing assholes is a win-win situation. Even the asshole might benefit from the wake-up call.