Bitcoin Forum

And the one before that was only 4 minutes apart...  ???

I don't really get the purpose of this thread. You know such things happen.
Sometimes there are 12 blocks in a hour, and sometimes not a single one.

I've never seen anything close to an hour for a block so this seems ridiculous to me, especially for a tech with the promise of fast transaction times.

I was hoping to start a discussion on the topic (this is bitcointalk after all)  ;D

It seems weird to me too. Can I now assume that the next difficulty increase will slow down now?

When this happens it can mean only one thing! Miners are on break(actually they are watching porn) and all the mining gears stopped mining!

It's very probable someone with a very high % of THS just stopped their gear for some maintenance! Everything will return back to normal soon ;)

Let's start the baseless rumor mill then. KnC had a power outage at their farm?  :P

75 min pauses happens quite frequently.  Now a 8 hours pause, that would be interesting :P

It could very well be a result of SELFISH MINING as Ghash has found back to back blocks and  has around 50% of the network hashing power just about and maybe even greater?The possibility is very Real! http://bitcoinmagazine.com/7953/selfish-mining-a-25-attack-against-the-bitcoin-network/
I'm part of the minority But the majority of people won't acknowledge the threat or just put there head in the sand and pretend the threat doesn't exist? and will always give them the benefit of the doubt?There's been plenty of spans of them finding 6 blocks in a row continuously which shows of this strong possibility  :o The threat is very real and the problem just keeps getting worse but majority doesn't want to do anything or even fathom the possibility they will say it's anything But ? Do some research and You can decide for yourself and don't listen to what people say?Do some googling Ghash has already has a history of double spending so it's not far out of the realm of possibility especially with  50% hashing power of network...... But we also have plenty of Selfish miners that will stick with them and they don't care about it as long as they are getting paid which is  just another part of the problem in itself......... Maybe I'm wrong ?but then again maybe I'm Right? The theory is as good and valid as anything else anyone has to say because nobody can prove that they are or they aren't?

ah very true...there has been a drop in the hashrate today. this makes total sense!

The difficulty of the network is set so that, on average one block will be mined every 10 minutes. This is an average and like all averages, each data point will be different.

If the hashrate of the network decreases after the difficulty changes then it will take longer then 10 minutes per block (on average). The opposite is true as well.

That magical day will not be coming for quite some time.  Not with BFL orders for 2014 being delivered in 2016  ;D

That's what will happen surprisingly often. Assuming that the difficulty is set 10% lower than the actual hash rate (it's probably nearer 7% now) then we'll see no blocks found in an hour about once every month. If the difficulty exactly matched the hash rate then this would happen about once every 17 days.

It's not a bug, it's not anyone doing anything malicious, it's just the way that mining is set up to work: http://hashingit.com/analysis/27-hash-rate-headaches

That article clarified a lot for me. Thanks for sharing it.

Doubt that will happen, its all about luck and diff here. its possible to have blocks minutes apart, as it is having them hours apart, but unlikely.
As far as diff is concerned, it will go straight up, no doubt about that, and that is becose more and more miners are joining and expanding.

I think the evidence is that it's already slowed down dramatically (although it's still going up at a very high rate). Certainly there's still a lot of scope for it to increase 10x more than it is right now. The BTC price strongly influences this as it increases the total available mining reward but ASICs are close to hitting a technology brick wall. That will mean the only way to get more hashing capacity for the same money is for hardware to be heavily discounted and eventually the hardware suppliers will hit margins that they can't go below. Similarly as we hit limits on the power consumption per unit amount of hashing we'll see energy costs taking a larger fraction too.

Once the expansion rate gets down to 5% (that could be this year or could be next) then statistical noise will mean we'll even see occasional difficulty reductions.

 You are spot on.    For the sake of argument   best asic = .4 watts for 1 gh at the wall plug .  The sp30 is close to that.    At 650 usd a coin and .4 watts  the sp30 stops paying for power at about a diff of  125 to 250     current diff is 11.7

Most 1th 1000 watts machine can't pay for power at 60 to 125 .

    so come winter  diff could drop   or maybe just maybe coins go from   650 usd to 3000 usd.  time will tell

Possible...but highly unlikely!

Would be good to see something different happen ?

Someone correct me but if there is no blocks for 75 minutes doesn't this mean nobody in the world can securely move their BTC from one wallet to the next.    Surely Im misunderstanding because that's really naff

hopefully Im totally wrong :o

It means that it took up to 75 minutes for some transactions to get an confirmation... Which is arguably very long.

Not that ridiculous, it's bound to happen. A Bitcoin block can be found at any moment, the difficulty is just chosen so that it will take on average 10 minutes. But mining is just like lottery, if another block is found 5 seconds after the first one, OK, it happens. If you throw a coin, 50 % of the time it will be heads. But if you throw it 10000 times, there will be long streaks of either. Bitcoin mining is not the same but 8 times the usual block time is not that unusual. A poisson process is a good model for how the blocks are found. You can work the probabilities out with basic high school math, it's not as simple as some discete probability problems such as coin flipping but a very simple model anyway.

Okay, some stats for your amusement just because I have not seen these before while lurking the forums:

The probability of finding the next block in

less than 1 minute: 9.5 %
less than 5 minutes: 39.3 %
less than 10 minutes: 63.2 %
less than 30 minutes: 95.0 %

As you are reading this, the probability that you have to wait more than one hour from this moment until the next block is found is about 0.25 %, small but significant and without checking the blockchain I am quite sure longer block times have been seen many many times before. It would be expected to see a 90 minute block time about once per year.

Based on the assumption of average ten minute block time which is the case when difficulty is "correct" for the current hash rate. Now that the hash rate is increasing, most of the time the difficulty will be "too low" and blocks are found on average more often than every ten minutes.

https://bitcoinwisdom.com/bitcoin/difficulty

According to this website it will not decrease. It is not an exact science, but it is generally accurate.

Yes. Some longer block times are to be expected. The difficulty has not decreased for more than a year and there is no reason to suspect it will do so anytime soon, though an exponential increase like this cannot go on for too long either.

Well well well!
After reading the forum a little I think I know why it took so long to find that block!

Maybe because LTC can be mined with asic now and all asic owners tried it!

Just my 2 satoshies!

They can be mined with ASICs, as could any coin, but not the same ASICs, because of the AS in the abbreviation - Application Specific. Litecoin proof-of-work has not changed so ASIC bitcoin miners can still only be used for bitcoin mining, that is a different task.

You can see those probabilities I posted, it is easily explained by chance that block generation took so long. About one in five hundred blocks take more than an hour so there it is expected even with rising hash rates that there is an event like that almost once a week (block genaration taking more than one hour). 75 minutes is of course significantly longer and more rare but that will happen too.

When observable conditions are consistent with what would be expected during an exploit attempt, and those conditions normally happen only about once a year as you have calculated, is it not sensible to report those conditions, even ahead of determination that an exploit is underway?

Information is a good defense against irrational fear, and the alert may stimulate some research into the matter?  Thank you to the OP for raising the notice.

So what,Go to eligiust and take a look

How is that related to this thread? We're not talking about a pool. We're talking about blocks on the blockchain.