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  1. Microkernels != modularity on What's Wrong with Unix? · · Score: 1
    Why the microkernel part? Although I don't have much experience in this, I'd say it should be quite simple, relatively speaking. Look at Linux, most of the kernel tree is drivers. The kernel itself is pretty small.

    While I agree with the rest of your post, Microkernels aren't about modularity. What are microkernels? kernels that delegate work to user land. Windows NT 3.51 had a 'micro'er kernel than the current versions of NT for example, in that the GDI was a usermode service. This proved to be so slow that they moved back the GDI into kernel mode. From a coding perspective, the GDI is still modular, it's just that it runs at a different priviledge level, effectively alleviating the need for context switches.

    As a general rule though, microkernels are problematic not because of their speed, but rather because of the advantage of having a microkernel.

    For example: if you put your filesystems in a user mode service and this service crashes, you have effectively lost track of any open file handle on the system, which is still up and running because the kernel itself wasn't affected. Problem is: the system is now completely useless. In fact, the system is in a far worse state than if it just simply had BSOD'd or kernel panicked. Why? Because applications won't be aware that half of their resources have just been sucked out from underneath them. For example: imagine a daemon of some sort that when it receives a socket transmission, sends back a response and writes something to a file. Now, it will send a response, but fail the file write, effectively violating application level state rules.

  2. Re:Amen! on What's Wrong with Unix? · · Score: 1
    What a troll you are. Aside the point in all three...

    Microsoft wasn't cited as a non brittle OS, a technology which happens to be used on Microsoft was cited as a step in the right direction.

    ext3 is cool, but it was aside the point of the post, which was a quote from an article that was linked by grandparent post - as in "on topic".

    Daemons should be aware of each other for dependency reasons. Read the friggin article from the Sun kernel group and stop trolling as if you know it all.

  3. Amen! on What's Wrong with Unix? · · Score: 4, Interesting
    The File System. Sure It Corrupts Your Files, But Look How Fast It Is!

    That's probably the single biggest problem I see with nix machines. Lazy filesystems have always reminded me of experimental planes developped by the cold war military to up the world speed record. Planes which would basically self destruct if they god forbid hit a pothole while taxying out of the hangar. RAID is obviously not a solution, and I find that backups - while essential for mission critical applications - should not be used as an excuse to allow for making a file system that is as brittle as this.

    As a broader comment, I just find that UNIX is a brittle OS. Before every zealot jumps on this statement I should clear up what I mean: the OS components are extremely lean, they do exactly what they're meant to do, but there's absolutely no inherent 'imune system' to the OS. su can go ahead unlink the root node, a power failure and the file system goes to hell, there isn't any cohesive way to manage machine state. Every daemon runs in its own little planet, unaware of everything else.

    The article the other day on /. about Sun's attempts at self healing software address parts of this actually. And other really cool apps like tripwire address other points too. But in general, the OS itself is completly stripped of an immune system.

    When Microsoft first introduced the Windows File Protection service, I was really pissed off they did something which should have been done via proper security measures (which common users were short circuiting by running as admin). But the more I face the idea, the more I realize that it's not a bad idea after all, proper code signing, system level integrity checks, basically a path towards actual 'self healing systems'.

    In general though, everyone has a long way to go still...

  4. Re:Fire away! on Comair System Crashes; Passengers Stranded · · Score: 1
    Agreed.

    (always makes me feel warm inside that you can have logical conversations every once in a while on /. =)

  5. Re:Fire away! on Comair System Crashes; Passengers Stranded · · Score: 2, Insightful
    Do you not know what a rollback segment is? It's what makes you run out of disk space while updating a table 1300 times larger than you thought it would be

    Yes, but you pretty much spelled out what my point was in that the n^2 complexity issue is unrelated to transactional operations. That is, a transaction is a transaction, it is scalable, so it doesn't matter whether the actual operation for computing stuff is O(n^2), the transaction is still a fixed cost. On a side point: I don't agree that because the problem is 1300 more complexe, the updates are 1300 times bigger. The problem is still based on n elements: it just happens that computing the solution of a problem with n elements takes n^2 time... the end result though is still n elements to update.

    That being said, I am fairly confident modern relational databases are scalable to the point of being able to handle a 500 fold increase (if only by simply slowing down to a crawl - but not crashing). If anything, it's probably internal application logic that wasn't able to handle the added computational complexity and at a certain point hit a hard limit of its scalability (some fixed sized arrays, or indexes of some sort).

    My comment about 'ran out of disk space' was more in the lines of "it's either an application fault, or something mundane like someone forgot to check if they had sufficient disk space" (something which can happen anytime due to neglect)

  6. Re:Fire away! on Comair System Crashes; Passengers Stranded · · Score: 2, Interesting
    I don't think they keep a SQL transaction running for as long as the flight hasn't taken off.

    SQL transactions generally last seconds and involve operations like "open tr, is there space in this flight?, reserve space, close tr". Not "open tr, wait for flight to fill up, close tr". Rescheduling or canceling flights probably isn't accomplished using transactions: it's application level logic.

    My personal diagnosis: I think it has nothing to do with the backlog, and that the system just melted under high strain (of millions of people trying to book other flights). Either that, or they ran out of disk space.

  7. Re:Well if I'm going to be obliterated by an aster on Asteroid Flies Under the Radar, Literally · · Score: 1

    And, don't forget: blowing pieces of this earth that belong to other people.

  8. A Mathematically 'better' calendar on New Calendar Proposal · · Score: 1
    I still find it mind blowing that nobody has ever thought of a lunar calendar, what with month/moon relationship of words in many languages I know.

    And it's mathematically much more perfect:

    13 months of 28 days (364) plus a single "New Year's Day" every year. Add in your 2 days of new year celebration every 4 years.

    I'm baffled because I figured this out when I was something like 12.

  9. Re:Incorrect assumption on Mathematics and Sex · · Score: 1
    "there is no method (omni-whatsit God providing details aside) of knowing which multi-dimensional person maps to the largest uni-dimensional life-happiness for you".

    My point is more based on the fact that "amount of happieness" kind of statements boil down to scalar math.

    What if amount of happieness is not a number, but a function of time, that the function does not have a limit at infinity (until the end of your life). What if the total amount of happieness is basically the integral of this time function. What if, this function is *not* integratable (cymbal crash).

    What if, everyone could maximize the overall 'world' happieness by choosing partners where the time function was the best for a specific period in time.

    What if I there existed a theorem that said that no single function will have a greater integral than two other well chosen functions combined and integrated (e.g. for any f0[n,infinity], there exists f1 [20,35], f2[39,65] such that integral of f1 + f2 > f0)?

    The answer, we don't know, and I don't think anyone will ever. But mathematically speaking, the fact that you can't prove such two functions don't exist is enough to say that all of the preceding discussions about mathematically going about things is absolute not rigorous.

    Don't get me wrong, I'm no heathen, I would really like to find my soul mate and live the rest of my life with her (or him, who knows). But I also find that a) the search for the soul mate can be just as constructive (if done properly), and b) that if we are going to go Mathematical on these sorts of problems, we need to stay mathematical, and examine things with pure logic, which doesn't allow for lax parameters such as "optimal happieness"...

  10. Re:Incorrect assumption on Mathematics and Sex · · Score: 1
    The fact that there exists an optimum person is pretty trivial to prove if you're willing to accept an axiom that no two people are identical.

    Absolutely wrong. It implies that your dealing with an ordered set. Just off the top of my head of unordered sets, any n dimensional space with n > 2 is ordered (think matrices), complex numbers fall into that category too. Saying the length of the vector can be ordered is changing the problem from an n-dimension space, to a uni-dimensional scalar space (the length of the vector).

    The norm is that sets are not ordered. Not the other way around.

    My point though is that, maybe, just maybe, you can't be happy with someone all your life. Maybe that is the fate of only some people, and that for some other people, life partnering doesn't work.

    That's much more sociological, and is basically opinion, but the above statement you make about math is absolutely wrong.

  11. Re:Incorrect assumption on Mathematics and Sex · · Score: 1
    I agree with the grandparent post.

    The fact that there exists an optimum person for this problem is not trivial. Personally, I think it's like a limit. It might be 0, 1 or +infinity. Then again, a function might not have a limit.

    Given that we are talking about "the rest of your life", I see the comparison to limits as very relevant.

  12. Wow cowboy's... on MD5 To Be Considered Harmful Someday · · Score: 1
    I know everyone is thinking "damn pirates, they can get their corrupted files", but another good example of something we don't want is OS signed files.

    Example scenario: some OS has a list of MD5 hashes of all of it's core files (drivers etc). At boot, it checks to see if the files are untampered, and if they are warns the user or halts the boot.

    Now imagine you could maliciously inject bad code (worm/trojan/virus/spyware) into this system, and you had a tool that knew exactly what extra random data to add to make the file have the same MD5 hash after your addition.

    If that becomes possible, then Hell will freeze over. Unless, of course, people don't use MD5 and switch to SHA1.

  13. Flash explained... on A Strange Streak Imaged in Australia · · Score: 1
    That's a good point you make. What it tells me, aside from the fact that it might be a tampered image (Which everyone already knew), is that in the case it's legit, the flash must have lasted a very short amount of time.

    Think of it like this: you take a flash picture of someone in pitch black, it doesn't matter if the shutter is set at 1/2 second, the exposure will only be as long as the flash (~1/40.000th second).

    That being said, the flash *is* actually blurred. IF you look at it, it looks blurred radially outwards. With the center being to the bottom right and more intense (indicating motion, but also explosion during motion).

    I personally think the plume of smoke has nothing to do with the artifact. I also have a hunch that tells me the flash is actually a much smaller object way *in front* of the lamp post. (not further behind). Don't ask me why, it's just a hunch.

    If I were to rationally come up with a hypthesis, I'd be inclined to say it's a firework-like object that blew up and never hit the water. That's what the flash looks like. Although, the trajectory indicates too high speed to be a firework. Maybe ammunition, or a fighter jet flare of some sort?

  14. Re:A Quick Lesson in Logic on Clean System to Zombie Bot in Four Minutes · · Score: 1
    Let's be clear, I'm not hyping IE up or dismissing other browsers. I use Firefox most of the time.

    But I think you underestimate the logic required to interpret a file that has missing tags in it. I've seen IE render half decently pages that even HTML Tidy (the w3c made HTML tidy *application*) couldn't fix.

    Does it have a shit load of proprietary attributes? Yes. Can it render pages designed for mozilla/netscape? No. Can it render W3C compliant pages? Most of the time - given that W3C compliant means no javascript, most browsers show those pages pretty much the same way. But you can't dismiss the fact that it's good at deciphering mangled code... and you can definitely not dismiss that as 'an easy thing', because, believe me, I've tried writing my own application to validate user HTML input. It's a nightmare.

  15. Re:A Quick Lesson in Logic on Clean System to Zombie Bot in Four Minutes · · Score: 1
    See, you know what the problem is with IE? And it actually was on slashdot a couple of weeks ago, but I ain't gonna dig it up for you...

    IE has the *highest* tolerance for broken HTML out there. You can have **hideous** HTML with no closing tags for tables, with interleaved tags etc, and it will still show something coherent. Mozilla browsers for example, will just show crap, the way it's meant to be: crap.

    IE does an exceptionally good job at recognizing what programmers meant, and not what they said.

    Too bad that's actually proven to have such a bad side effect.

  16. A Quick Lesson in Logic on Clean System to Zombie Bot in Four Minutes · · Score: 2, Insightful
    Some of the problems are caused by user error, but certainly the OS is to blame as well. For example, IE has the crappiest default security settings. Changing them breaks a lot of sites. Finally, IE is integrated into Windows, so security issues suddenly are ten times worse.

    In other words:

    1) IE: bad security

    2) IE: good security => breaks sites

    3) IE is Windows (let's assume)

    4) Windows breaks sites/Windows has security issues

    Oh sigh... man, I'm not even going to look for an analog syllogism because it's just so obviously wrong.

    What I get really irrate about is this little fact: 90% of sites out there that tout anything cool don't work without IE. That's not to say IE is good, it's just to say these people who designed the sites were LAZY and fucking did not follow W3C standards. On top of that, most of them blatantly used IE's lax security to get cool features. Changing security settings for IE, or simply using Firefox breaks those sites.

    So here's the tricky part class: it's not IE or firefox that's broken, it's the sites.

  17. Re:Correction: on Tin Foil Passports? · · Score: 2, Interesting
    Ummm... not really. Assume you have a positive current on the center wire. Using the right hand rule, this creates a positively charged, cirularly symetric E wave that radiates outwards (think throwing a rock in a pond). If you pass the negative equivalent of this signal on the outer shielding, you generate an opposing E field that will directly cancel the internal one. Again, you don't have to ground the external shielding.

    That's the part where grounding comes in: grounding essentially means connecting to a capacitor of infinite capacity (the earth), which is able to always supply you with an equal and opposite field E. The scenario you describe is a very specific one illustrating how you would shield out from one particular intensity (or function wave) of the internal E field. This is more akin to noise cancelation... it is not shielding: in shielding, you can cancel any function wave (even if it is chaotic - e.g. static noise) because of your infinite capacitor.

    Again, I believe this proof we are after is based upon a provision, such as "the overall charge of the system" or something of the like. Think of grounding as having a system with infinite capacity.

    PS. I will not really discuss the previous points you and I made because I was trying to simplify the situation into layman's terms. We cannot make a proof using "fleeing" charges and what not. The proof is mathematical, and I am suggesting we are missing a crucial requesite that neither of us remembers. The Coax cable thing though, I am positive of, it is without a doubt in my mind a real world application of a Faraday cage. It is also why computers and sensitive electronics need to have a ground plug: so as to avoid data corruption from stray RF fields emenating from the scooter rolling by down your street. Only two plugs (phase and neutral) are not sufficient.

  18. Re:Correction: on Tin Foil Passports? · · Score: 2, Informative
    See, here's how I remember it from class:

    A Faraday cage is a conductor, so charges are free to move inside.

    When the outside is exposed to a negative charge, all the electrons 'flee', and leave a positive charge on the surface. They 'flee' to the other side of the surface, to bunch up in negative charges: that is, inside the cage. Hence exposing the inner volume of the cage to negative charges, exactly at the level of incoming negative field to be exact.

    When the cage is grounded, 'fleeing' electrons are not accumulated on the other side of the surface, but rather are dissipated, leaving the inner surface of the cage perfectly neutral, and hence not exposed to electrical fields.

    An example of this is Coax cables. Coaxial cables are basically a faraday cage made long. Coax cables are perfectly immune to interference *only* if the outter core is grounded. If it is not grounded, they are subject to any interference the whole system is subjected to.

    Wikipedia seems to have it partially right, but not fully:

    Faraday stated that the charge on a charged conductor resided only on its exterior, and had no influence on anything enclosed within it. To demonstrate this fact he built a room coated with metal foil, and allowed high-voltage discharges from an electrostatic generator to strike the outside of the room. He used an electroscope to show that there was no excess electric charge on the inside of the room's walls. [Emphasis mine.]

    I am fairly sure about this as a whole (about 99.995%), but unfortunately, it's been too long for me to remember the math behind it all. What my instinct tells me is that the proof by Gauss' law must have an obscure provision that is not listed in the Wiki entry either. A condition such as "all charges in the system must be within the sphere" or something of that nature.

  19. Correction: on Tin Foil Passports? · · Score: -1
    A Faraday (one r) cage needs to be grounded or it won't work. A tin foil is sufficiently 'cage-like' (when it comes to passports), but it isn't grounded.

  20. Re:it's a new age on Blending Mice and Men · · Score: 1
    "An animal may have rights when it asks for them."

    By that account: retards and comatose people should have no rights.

    And while we're at it, those pesky black slaves that were imported from Africa not so long ago, they shouldn't have rights either, they're just uncivilized barbarians who don't even know how to speak (english)!

    And then again, Parrots could be new citizens.

    It's all too simple to reduce the problem to that really. It reminds me of two things:

    First, Decartes' musings on how humans might as well just be robots. That we will have no proof ever that anyone except ourselves is conscious.

    Second, a quote (of a quote) from Ghost in The Shell 2 that goes like this:

    Sadness over a bird killed, but no sadness over a fish killed. Lucky are those with voices. - Saitou Ryokuu

    I hope you don't endorse what this Supreme Court Justice thinks or says.

  21. Re:Stuff on the ground on A New Elena Story · · Score: 1
    It's not an encyclopaedia or a history text, meant only for dry facts.

    I agree, and I'd also like to add something here: in North America, people have come to expect all their information input to come from media (mainly TV), and so have come to an otherwise absurd point of view that for example, films should for some reason be 'historically acurate'.

    I just love it for example, when people shat on "The Last Samurai" because it wasn't historically acurate.

    My point is: if you want historical accuracy, you shouldn't be watching a 2 hour Hollywood movie... nor should you be looking at pretty images from a website somewhere on the web. You should be going to your local library and digging up the information - and EVEN there, you should always be cross checking the data to make sure it's accurate and not slanted...

    That's the *only* way to avoid history from 'being written by the victors'. Not by shitting on Jerry Bruckheimer for a distorted portrayal of the events at Pearl Harbor, or Ridley Scott's pro-american view of the Mogadishu events in "Black Hawk Down" (both of which, to be clear, I thought were shit ass movies... but not because they were inaccurate)

    So, if you're gonna shit on Elena, I dismiss any arguments about accuracy as being 'irrelevant'. If anything, I will criticize her comments about how she loves pubs or whatever. I find them out of place. I prefer her (somewhat skewed at times) social commentary and anecdots about people's reactions of the time/place.

  22. Re:Stuff on the ground on A New Elena Story · · Score: 2, Interesting
    Yeah, this also explains a certain amount of the 'arrogance' that is felt by Europe towards America. When you live in a city, such as Rome, or Istanbul or Vienna, and you have monuments that date back *thousands* of years, you can't help but find even New York dull at times.

    I lived in Istanbul for a long time, and a lot of the historical 'relics' are still in use in modern days. Cable pulled "subway" carts from the turn of the century, ferry boats from the 20s. You take it for granted when you're there, until you come to a 'new' country and realize, there's NO historical background at all.

  23. Re:Slashdot crowd sets reading record on A College Guide to EA · · Score: 1
    Yeah, but when you find an article titled "First Fusion Reactor Built by Raelians", and you start skimming through the article and see things like "Alchemy", and "perpetual motion", it doesn't take long to realize it's horse shit.

    Said Alchemy: People at EA work long hours, in large part because of their great passion for making games

    No serious programmer, or manager, would argue that long hours are part of a regular schedule.

    Everything exposed so far about EA points to the fact that it's a local sweat shop, one step above actually outsourcing to India. And this academic 'prof' is just proof that they're paying someone to recruit more 'children' to work for pennies.

  24. Re:Factually False... on A College Guide to EA · · Score: 1
    I think EA has a larger parking lot.

    Reminds me of the simpsons episode where they show the Epcot center with a ginourmous empty parking lot and a guy at the ticket booth.

  25. Re:Telling Quote on A College Guide to EA · · Score: 1
    It's a boon for any software operation, and because this jack-ass of an academic doesn't know his ass from a door knob, he couldn't tell...

    The fact that WinFS isn't out yet is because of this.