I tried compiling a version of my code, LOOP_LOG2=1, and two extra pipeline registers with Register Balancing enabled. It couldn't even get past Mapping, with an area constraint error  The LOOP_LOG2>0 code isn't terribly efficient. There are some changes to make it a bit better in the partial-unroll-opt branch on my github repo; I'll see if I can get them merged in to DE2_115_makomk_mod and send you a pull request at some point. Just put together an untested port of them to Xilinx and got an apparently successful synthesis run for the XC6SLX75 at LOOP_LOG2=1 and 50 MHz. This is with some experimental block-RAM-as-shift-register code that I'm not sure will work, though. Will upload the code in a bit. Edit: Also, the DCM_SP doesn't seem to work quite the way I might expect. Curious. Edit 2: Aha - with the way this code uses it, the CLKFX_DIVIDE and CLKFX_MULTIPLY settings are effectively irrelevant, as is CLKDV_DIVIDE. Edit 3: Can't quite get it to hit 100 MHz with LOOP_LOG2=1 on the XC6SLX75 (actual period = 11.045ns). Looks like I'd need to port over the patch for the extra pipeline stage to compute the initial value of H+K+W[0]. Untested 50Mhz code dump here |
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To make the example more clear:
1. Let X = illegal file
2. Let Y = completely random bitstring of same length as X
3. Let Z = X xor Y
4. Post Y on one server, say a google blog. Post Z on another, say a wordpress blog.
Now observe the following: Y is a totally random string, so clearly it contains no information about X. What about Z? Well think about it: if I take some fixed string X and XOR it with a totally random string, what do I get? I get another totally random string. So Z is also a totally random string, containing no information about X either.
So now we have two servers both storing totally random strings. Clearly, neither is illegal alone. But their XOR is illegal. Who commited a crime, other than the uploader?
Does either of them have a purpose other than being able to be recombined to reconstruct the original illegal file? If not, what's to stop the courts from ordering both to be removed? (Obviously if one of them does have a purpose other than being able to be used to reconstruct the illegal file, the other one must contain the information about said illegal file; due to the way the two files have to be constructed it's impossible for both of them to have been created for another purpose.) |
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Exactly. So why are you obsessively focused on one small factor and ignoring the universe of other much more significant factors? The only explanation I can think of is that you think of progress as a zero sum game and therefore you focus on the cases where X gets something rather than Y. But you are missing the forest for the trees. The world is not a zero sum game, and the important factors are the ones that lift society as a whole. You are obsessed with helping the ditch digger at the expense of the CEO and missing the fact that fact that real progress lifts everyone and that is what you should be focusing on -- how can you lift all of society further and faster.
Congratulations. You've missed the entire point of my argument whilst spotting why I wasn't complaining about the existence of wealth disparity in general. The issue here is not that the ditch digger has more money than the CEO, but that the poor have to justify their money in the eyes of the market in a way that the rich don't. If a ditch digger fails to dig efficiently they'd get the sack, but there's no way of sacking the wealthy if they enrich themselves at the expense of real progress - the only way they can lose their wealth is through gross incompetence. This doesn't really help "lift all of society further and faster". ( Edit: Also, there's a lot more opportunity for someone who'd be better at digging ditches to replace someone who's worse at it than for someone who'd be better at investing large sums of money usefully to replace someone that's worse at it.) CEOs are actually a good example. They can run company after company into the ground through bad management and still leave each job with lots of money, because the other board members that appoint them are also members of the CEO class and in on the take. You've got an entire group of people enriching themselves at the expenses of driving others down. As an example of the other side of things, I actually have a lot of respect for Warren Buffett. He really does seem to have got where he is by investing money sensibly in a way that benefits society in the long run. Of course, he's not very popular on these forums... |
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Ray Kurzweil has some nice insights into measuring innovation and growth from a technology perspective.
Ray Kurzweil comes up with impressive-sounding ideas about the future that turn out to be wildly optimistic. |
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you would have to be very public about it, and always have cameras streaming live, that way if the US did try something the whole world would see it. Two words: jamming devices. Worked very well for the Israeli government. |
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SHA-256, by its very nature, cannot be optimized.(1) The Open Source FPGA Bitcoin Miner uses 75K Altera Logic Elements to perform a full Bitcoin hash per clock cycle. This translates to somewhere between 225K gates and 975K gates. You say you get ~4 Bitcoin hashes per clock cycle from 45K gates. This is massively incorrect on your part. Yeah, agreed. Even though I have no experience with ASIC design whatsoever, it's pretty obvious that 45K gates isn't nearly enough even for just the adders of a 1 hash per cycle design, let alone the rest of the logic required. |
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So you're saying that it might give me the prompt "You must pay .0005" and it will take that much out, or will it still round it up to .01 BTC?
It might just pay the .0005, it might pay .01 BTC, or it might pay some amount in-between - depends on the value of the coins that the client selects to make the payment with. There's no way of predicting this in advance. If I'm reading the anti-dust code correctly it could even charge a sub-0.01 BTC "fee" without prompting at all, though that's probably fairly unlikely to happen in practice. If, tomorrow, everyone started using a patched client that allowed 0 fees, NOTHING WOULD CHANGE AT ALL in the Bitcoin world, except a few pool operators would have a bit less side income. Miners mine today for BTC, not for transaction fees. Maybe this will change in the future. But we can worry about that in the future.
The fees aren't meant to be there to support the miners at the moment, they're there because without them it's too easy for people to spam the blockchain with bogus transactions that send money to themselves again and again. This apparently did happen for a while. |
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Now, there's one output of 0.99 and one of 0.0095 (the change). The remaining 0.0005 are meant to be the fee.
Now the client realizes that one output is below 0.01BTC and the anti-spam-fee of 0.01BTC kicks in, so you get no change at all.
This is just a guess, I have no clue if bitcoin tries to avoid having <0.01BTC for change.
I seem to vaguely remember one of the developers saying in IRC a while ago that Bitcoin deliberately gets rid of any change left over from a bitcoin transaction that's less than 0.01 BTC by giving it away as a fee. Something about bitdust removal... Edit: Yep, bingo! // Fill a vout back to self with any change
int64 nChange = nValueIn - nTotalValue;
if (nChange >= CENT)
{
[ snipped code here that actually give you change back if it exceeds 0.01 BTC ]
The anti-spam fee was dropped to 0.0005 as part of the fee reductions from what I can tell, so that couldn't cause it. |
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So if I'm understanding this correctly, the person with a red username with an [A] next to it saying "Nope. Can't sell a subreddit." in a comment is one of the Reddit admins? |
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Ah, so it's a repost of that post from the SA forums - no wonder the .exe names looked familiar. I wonder if he ever figured out where it came from? |
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hmm ok, i get it. So what is exactly being ddos'd. Is it on ip level or application level? or both? Too much ip traffic to handle or is the server bogged down by requests?
I think some of the problems started with the botnet owners unintentionally bogging down the servers with requests, but all the actual intentional DDoSes are based on sending large amounts of data as far as I know. |
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You are assuming the options contracts would be honored. A better solution would be to short-sell the bitcoins, then buy them up at after panic ensues.
The trouble here is: how can the person lending you the bitcoins to short-sell trust that you'll be able to repay them? The usual solution is to do your short selling via a trading account at a trustworthy institution, but Bitcoin is very much lacking in those. It's one of the reasons you're unlikely to see any Bitcoin naysayers putting their money where their mouth is; if you think that Bitcoin is going to end in disaster letting your money anywhere near it is a bad idea. |
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That money had to come from somewhere, yes? It isn't elephants all the way down.
At some point some miniscule portion of it did, sometimes centuries ago. Remember that there's a lot of inherited wealth out there. That pre-existing wealth was earned by that person by providing value. It's that person's earned labor in the end. Possibly. Really? So how much is the labor of a ditch digger worth if there are no shovels? How much is the labor of a ditch digger worth if there are no irrigation systems that require ditches? Some of the value comes from the laborer, but some of the value comes from the circumstances that make that particular labor valuable, which is external to the laborer. If there's no shovels or no ditches that need digging then no-one can make money digging ditches. My point is that if someone makes money digging ditches, the reason they earn that money and someone else doesn't is because they're skilled at ditch-digging. However, if someone makes money from providing access to money or scarce resources they control, the reason they earn that money is not because they're particularly good at doing so but because they're the ones that own that money or those resources. (About the only saving grace of this system is that if someone's really, spectacularly incompetent they'll lose their wealth to someone that is.) It has nothing to do with who is the "better person". You don't have to be a good person to deserve to profit from the invention of the shovel, the construction of farms, and whatever other environment you are lucky enough to be born into. Again, these are things that whole societies receive the benefits from rather than one particular person. |
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I went to read that thread, and discovered that those same people think robbery and organized crime are GOOD ideas. Makes it a bit harder to take them seriously.
Ooookay... don't remember seeing anything like that over there. (Here on these forums, perhaps, in a sense...) |
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You do this by saying "The value is X today, but it also has additional value because it will deflate. Let us calculate that additional value." The X already includes the deflation value, just as the future X's also include the predicted future deflation value past that point. There is nothing else to add.
Aha! I have a feeling there's a problem with one of your assumptions, and I suspect may be the process by which the value of X takes deflation into account. There's already something driving the value of X - it's the prices of goods that can be purchased for X - and I don't think that in general the value of X can be such that it both matches the prices of goods that can be purchased for X and takes deflation into account. This is quite tricky to think through, though, because that's a fairly fundamental assumption of economics and I've never been that good at it at the best of times. ( Edit: Ah, that's interesting but not it, I think. However: changes to the value of X due to anticipated future deflation affect the rate of price deflation themselves, and that may be an issue.) If you want to say "The value is X today, but it has additional value because it will deflate", your X must be the current value less the deflation value. And the future values you calculate the present value of must also be exclusive of the deflation value. If the deflation value is actually infinite, then the present value less the deflation value is infinitesimal, and the future values less their deflation values that you are adding to the present value are also infinitesimal, so you have a sum of an infinite number of infinitesimals which can be, and in this case must be, finite. This is especially so because a time frame of over, say, 1,000 years is self-evidently absurd. Nobody can be confident something will deflate for that long. Heck, we may not have physical bodies in 1,000 years.
You can't actually add up infinities like that. In any case, if we're not entirely certain about the future, then it's a lot simpler: over time we acquire new knowledge about future deflation, and unless there's suddenly some reason to consider it less likely this extra information will drive the value of X up over time. (Except for that one small outstanding issue...) |
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Well, hells bells. Imagine how much they are missing out on by non buying the lottery ticket with the winning number. Opportunity cost is what you lose by not doing the next best thing. What makes you think you know what the next best thing is?
You can't know whether the lottery ticket you're thinking of buying is going to be the winning one, in much the same way as you have no idea how much your bitcoins will be worth in a few months' time. Choosing to buy a lottery ticket is actually more analagous to leaving bitcoins from mining unconverted than to converting them to USD. If you don't want to add to a losing position, then why the hell would you want dollars? They've lost 96% value in the last hundred years.
You'll be dead in a hundred years' time. More importantly, no-one just stuffs dollars under their mattress and just leaves them there for a century, and while the dollar may be losing value it's at a slow and consistent rate. If the dollar was losing its value at the rate bitcoins have been lately there'd be mass panic. |
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Concentrated costs and distributed benefits. Even if we assume that the skeptics are sincere, that is not a rational reason for continuing to post here. You're assuming that people are rational and that "someone is wrong on the internet" isn't a good enough reason. More than that, you're assuming that no-one could be motivated by pointing out the flaws in arguments for the benefit of others; a lot of people do seem to be. Presumably their goal is to see bitcoin fail, but according to them, it is doomed to fail anyway, which makes their posting an unnecessary expenditure of time and effort. Of course, there's more than one way Bitcoin could fail, and some of them will harm more people than others. The next possible explanation is they want bitcoin to fail FASTER than it would without their "help". The problem with this is that, even if they succeeded, they and their friends reap only a tiny portion of the "benefits" resulting from their time and effort. Again, you're assuming that there's no such thing as altruism. If Bitcoin is going to fail in a ponzi-like fashion as some suspect, the longer it goes on for the more people will end up losing their money to the early adopters. Not only that, but if this is going to happen then the best way of speeding up the collapse is to help people avoid losing money to it. Ironically, "destroying" Bitcoin in this way could even help it in the long term by making it more likely to be used after the speculation implodes. So the next reason after that is that somehow bitcoin is a <i>particular</i> threat to financial prudence and all right-thinking friends of civilization. To which it needs to be asked- which is it? Either bitcoin is a joke or it is a dangerous threat, but it can't be both. It can be; it can be a joke that would be a dangerous threat to financial prudence and society if it did somehow succeed. It's worth arguing both ways because there are people out there that aren't convinced that Bitcoin will fail and might be more amenable to arguments based on what would happen if it succeeded, and because even if you do believe that it won't work there's always the slim possibility you could be wrong. This is an old technique. Which leaves one last possibility: These skeptics are in it for the entertainment value, party crashers who piss in the punch bowl. There's a name for people like that: trolls.
Possibly, and the discussions here are providing a lot of entertainment value - not just to Something Awful either, have you seen some of the comments on IRC? However, if you read that SA thread, you'll notice a lack of users conspiring to undermine Bitcoins; they really do genuinely think they're a bad idea. |
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Hey guys,
So lets take off our tinfoil hats and keep the Mtgox hack as a isolated incident. If this is not an organized attempt to discredit bitcoin, what does the DDOS'ers gain by attacking pools? Whats the point?
There are people with botnets that think mining bitcoins on them is a good way to make money. The pool owners disagree with this and have been cutting them off, partly because the number of low-hashrate users is disruptive to pool operation. You figure out the rest. |
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I wonder if they are just going for the 15 BTC scam, or whether they will also try for the additional $2700. But it's fun to think about mining at 5 Gh/s and only pulling 400 watts or so from the wall.  In theory that's achievable with FPGAs right now, it's just not cost effective because of the huge up-front cost of the FPGAs. |
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Does anyone know what the cost of these 28nm Artix 7 chips are? I've been looking through and the XC7A350T looks promising with 350k LUs. From the text on the site it looks like they're using this chip to replace the Spartan 6's. Right now they're not available at any price as far as I can tell; initial samples are meant to be shipping in the first quarter of 2012, with production quantities available who-know-how-long later. This is also wildly off-topic though, given that this thread's about building boards with actual FPGAs that are available now. Expect to fit at least 4 hashers in the XC7A350T unless Xilinx have done something daft in the design again like they did with Spartan-6, which is entirely possible. I have no idea about clock speeds; estimating that would require a full ISE license. |
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