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Comment Re:1024-fold (Score 5, Informative) 210

It takes a long time to compute the size of 20 files when a division by 1000 takes 300 odd cycles on a 10kHz machine. It doesn't take such a long time when a right shift 10 takes 1 cycle.

This must be the most clueless post about the 1000/1024 divide so far. It never had anything to do with the computer's performance, it's that when you build a digital computer a lot of things will be sizes of two because what you can address with n bytes will be 2^n. Physical memory, memory pages, caches, buffers, floppy and hard drive sectors all the "microunits" in the computer are powers of two. Hint: No actual hard drive gives you 1MB = 1000000 bytes because it's not divisible with 512, in reality they give you 1954*512 = 1000448 so they don't underdeliver. Actually make that divisible by 4096 for modern HDD drives with 4K (no, not 1000) sectors.

There is a single reason why computer scientists usurped the prefix kilo and that is because they needed to describe "one thousand and twenty four bytes" - or multiples of that - very, very often. They needed a shorter name, they never needed the unit "1000 bytes" and so "one kilobyte" became their shorthand for 1024 bytes. And unless you're really good at doing math in your head, tell me how much is seven kilobytes exactly? (And if you answer 7000 I'll slap you). We still say 512GB of RAM. Nobody wants to say 549.755813888 GB of RAM, because multiply that with a billion and you have how many bytes that is. It's not some nice, round number.

Either way you're going to run into some f*cked up conversions if you mix GiB and GB, which I'll use now for clarity. If you have 512GiB of RAM (hey, servers do) and load 512GB from disk, how much of your RAM have you used up? Now while you're calculating that, this other person who uses a GiB system says so that was like ~477 GiB so like ~35 GiB free? Or you have to say you have 549.8 (rounded) GB RAM and use exactly 512 GB. Of course in reality file sizes are probably a rather random size so you'll have two long floating point numbers. At least with base 2 you just have one, because you have exactly 512 GiB RAM.

And when you do have base 2 numbers then multiplication/division gives other nice base 2 numbers like 10 MiB / 2 KiB = 5 KiB. 10.485760 MB / 2.048 KB = how much? It's a lot uglier if you numbers are 2^n values, which again they will be a lot of the time. At least far more often than base 10 as long as you're working with the computer itself and not business data or whatever. If you for example want to make something fit in L3 cache to optimize and algorithm, the numbers will be in base 2. You can't "bugfix" your way out of that.

Comment Overkill much... (Score 1, Informative) 210

So the highest MP camera I could find in a normal store is 40 Mpix (Pentax 645D) * 14 bit RAW = 70MB/picture. So good for 70,000+ photos. Or the Panasonic HC-X1000 4K/24 & UHD/60p camera just released, 150 Mbps = 7-8 hours continuous recording. But I suppose it's good for when you want to carry 10 BluRays in your phone. Whoops, wrong format not microSDXC. I guess there's a niche for this since they made it, but I kinda fail to see the target market, unless it's the "give me the biggest and best you got" crowd.

Comment Re:Actually a good thing. (Score 3, Interesting) 215

Well, if you want Kickstarter to be your go-no go decision maker then you can't wait so long you're already pot committed, as they'd say at the poker table. If you're half finished and your Kickstarter fails, what do you do? Throw away all that work and start over on something else? Try to salvage it and publish something, even if it has lackluster appeal? Not to mention then you must go it alone, if you already know you can finish it alone do you really need Kickstarter? My impression is that Kickstarter works best when your "selling points" aren't your product but your reputation and history. I donated fairly big to the Musopen project because there was quite a bit of history to show that yes, they're serious about creating free music but lacked the funds to do it. I'd be very weary of people with just photoshop and powerpoint skills.

Comment Re:CDC guilty of correlation == causation (Score 1) 291

A few thousand years is no time at all in evolutionary terms.

So I assume you're arguing that bread is something we haven't yet evolved to safely digest?

I agree: I'd go as far as to say that gluten intolerance and diabetes could be considered part of the evolutionary process, weeding out those of us who lack the genes to safely digest high carb, cereal based, diets.

Comment Re:It's a bad sign (Score 1) 223

Well even if you got most people to agree this is a bad thing there's also the small problem of what line of action would ultimately make things better and not be horribly much worse in the meantime. It'd be an awful shame if it ended up being "meet the new boss, same as the old boss".as they too are corrupted by the establishment, now you have a third party whose politics you feel is nuts as well. Or perhaps I should say that the other way around, chances are they'd have to sell out to get to power otherwise they'd be fought tooth and nail every step of the way. There will be a massive gloom and doom campaign about all the horrors that would bring and people get scared. Even if what they have isn't fair the world isn't unicorns and rainbows and it could get a whole lot worse.

For example many of the people in the Arab spring, they topple a secular dictator in the hope of freedom and democracy and end up with extreme religious fundamentalists taking over the country. Granted, it probably wouldn't come to that but even if we take the Civil War that ended slavery and whatnot there's probably a whole lot of injured or dead soldiers and civilians, people who had lost someone or all their belongings or property who'd rather wish they'd let the Confederacy go. It's easy to point out the flaws in the old system. It's hard to make people believe in change. It's much harder still to make change. And no, I'm not trying to point out one politician in particular they all tend to backtrack on their promises once they get into office. What is going to make people believe you're actually going to be different?

Comment Re:In Google's Defense... (Score 1) 194

I also think you have to consider Google's risk/reward here. They wanted to pass the test and most of all they did not want to get involved in any accidents, even one where the car was driving technically correct but "unhuman" as that would be used in no small about of FUD. They passed, they got their license to drive, they got the PR and the news that they couldn't drive a roundabout two years ago is nothing compared to the bad PR they'd get for crashing in a roundabout.

And the railroad thing was just policy, it can't be that much harder than crossing a priority road. Or maybe they just hadn't bothered to implement that logic, since almost all crossings in central areas have signals/gates. I just checked here in Norway and all public roads now have that, there are ~3100 unsecured crossings but all on private roads.

Comment Re:Technobabble... (Score 1) 370

I think "a filesystem with ECC (like memory) and ACID (like a good database)" is as close as you come for an elevator pitch. I've had bits flip, whether it's in memory or on disk or in transit I'm not really sure but it happens. Like for example I create "known good" PARs for a 5GB video and later it fails CRC, If you use a hex editor compare tool it'll show a single bit difference. Backups are neat, but you really want control over bit rot - real bit rot - so you don't end up with slow corruption. ZFS pretty much makes sure that what you take backup of is good.

Comment Re:At $281, a bit expensive for a tablet CPU (Score 1) 51

Intel seems to be a full generation behind ARM in making efficient chips, but has used the 2 generation head start their fab has on everyone to cover that game, and then some now.

Intel has been very good at making efficient CPUs, but not systems. If you want to make a <5W SoC there's a whole lot of other skills you need than a 15-150W processor and Intel has clearly been on a steep learning curve there. Also they've been geared a lot towards efficient computing, while the chips that go into phones and tablets are far more about being efficient at idle and light load. Intel has been learning many new tricks to only power up what they need in the lowest possible power state for a short a time as possible. The improvements for a processor running at 100% load 24x7 has been far more moderate.

Comment Re:Can someone explain to me (Score 3, Informative) 123

You are currently modded +4 Insightful for having claimed, essentially, that the HST repair and upgrade missions could have all been done by unmanned systems. I could have modded you as you deserve. I could just ask for a citation - you're making an extraordinary claim there and you really do deserve to have to back it up or retract it. Instead, I'm taking a couple of months vacation from Slashdot

Good, because you're putting words in his mouth. I could do math with pen and paper, without computers and calculators and my answers would at least theoretically be just as correct but it wouldn't be cost-efficient at all. It's an apples and oranges comparison but Hubble cost:

From its original total cost estimate of about US$400 million, the telescope had by now cost over $2.5 billion to construct. Hubble's cumulative costs up to this day are estimated to be several times higher still, roughly US$10 billion as of 2010.

Space Shuttle program cost:

The total cost of the actual 30-year service life of the shuttle program through 2011, adjusted for inflation, was $196 billion. The exact breakdown into non-recurring and recurring costs is not available, but, according to NASA, the average cost to launch a Space Shuttle as of 2011 was about $450 million per mission.

The numbers we'd really like to know though is that out of those $2.5 billion to design and construct, how much would it cost to just make a new Hubble and launch it. Just the five servicing missions (confusingly named 1, 2, 3A, 3B, 4) alone at $450 million each - that's aggregate, not marginal cost though - would be $2.25 billion. It is certainly possible to argue that science would have progressed further without the Shuttle program, all things considered.

Comment Re:Are you fucking serious? Tell me you aren't! (Score 4, Interesting) 198

There are certain ways ACID compliance is important and certain ways it is not, in fact sometimes it's a hinderance. In particular the following:

One patient's records must be consistent only with itself, you don't need the whole patient table to be consistent. It's a problem because you do need to have cross-table consistency (patients, episodes, diagnosises, treatments, medications and so on) which can lead to locking issues while they're really millions of records living in parallel. Really I'd like to treat them as millions of microtables that happen to share the same structure but never cross lock.

Perhaps in a hospital you can do synchronization at a database level but for an exchange or common journal you have to assume records come in asynchroneously, your general physician might finish some paperwork while you're in emergency care at the same time as a lab result you've waited a week for comes in. The actual ordering they're applied in doesn't matter, there must be rules so (A,B,C), (C,A,B) and (B,C,A) all end up the same result. This means you can relax the hard synchronization of for example a bank account where it is essential that the transactions are applied in order and rejected if you're overdrawing your account, but that's hard in SQL.

That doesn't just apply to the ordering of writes but also querying. If two people at different hospitals tries to pull up your medical records it is important they're not corrupt but it's not essential that an update being distributed is presented to both or none. In fact, for essential robustness they should be able to continue working independently if the connection is broken and when the connection is restored the records are reconciled. That kind of shard and merge is generally a problem relational databases don't handle while the distributed synchronization is rather essential and implicit in NoSQL solutions.

Comment Re:SSDs will outpace platter drives (Score 1) 296

There's still a >10:1 cost difference between 4TB HDDs and 1TB SSDs and SSD prices are not dropping that fast. Current SSDs are already on the bleeding edge of processing technology with 16nm MLC so there's fairly limited density increases and big durability issues ahead. I guess the wildcard is 3D NAND, but much like going multicore for CPUs it's a substitute. However, they are taking over all normal end user uses in cell phones and tables and laptops, it's just the big bulk storage left.

Comment Re:No "standard" iPhone size? (Score 1) 730

I think Apple is dropping the ball by not even offering a smaller sized iPhone.

Unfortunately the whole market has leaped off the deep end on this one with "small" models bigger than the old flagships like for example the LG G2 Mini is 4.7", Sony Xperia Z3 Compact is 4.6" and the Samsung Galaxy S5 Mini and HTC One Mini 2 are both 4.5" - just as big as the new iPhone. I won't even comment on the 5" LG G3 Mini, as opposed to the full 5.5" version. In fact Apple is the only one who calls a <5" screen normal anymore. Obviously with a smaller screen and smaller phone you can't put the biggest, fastest and most features in it but I still find it disappointing that nobody takes the small sized phones seriously. I'm consider the Z3 Compact as it seems to be a decent compromise, but will wait until the reviews are out.

Comment Re:Deprecation shouldn't start at the browser (Score 1) 108

I'd love to walk into my bank

Good for you. Mine is all e-bank and I tend to like it that way. Same with most the e-tailers I shop at, the intersection with physical retailers is slim. How do you visit Gmail or Facebook? Speaking of which, people often have a different third party between them and whoever they're communicating with. You could always pretend it's not signed you know, what would you do? Send an email, asking them if that's their real certificate? Try to verify it through your "web of trust", which includes a bunch of dimwits who'll make the CAs look good? No, I wouldn't trust them for real end-to-end encryption but it's mostly good enough.

CAs takes the fradulent redirect threat down, but they could always just hack your computer and keylog everything, they could hack the bank, it could be an inside job, they could social engineer you into thinking this is a legitimate certificate update or they could social engineer the bank into thinking you've made a new certificate or whatever. It doesn't matter how many inches of steel the front door is if the rest is plywood and glass windows. Direct out of band secure exchange is of course technically the best, but also the most inconvenient. I guess you should also swap giant OTPs, wouldn't want to trust AES right?

Comment Re:Contacting BBC, via VPN (Score 5, Informative) 363

There's also that despite their public funding, which means they could give their content away for free, then instead try to leverage it for profit as hard as they can.

Tax some (UK population) and give benefits to others (rest of the world) is not socialism, generally the rule is everybody pays and everybody gets. If the former doesn't hold, you can't expect the latter to hold either so I perfectly understand BBC Worldwide charging for their content.

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