Bitcoin Forum

https://github.com/gavinandresen/bitcoinxt/commit/821e223ccc4c8ab967399371761718f1015c766b

Finally some movement! Can't wait to see this out on Bitcoin XT's production release!!

So, 8MB and then doubling every 2 years.

I think block height rather than timestamp would be better for handling the doublings.

What is so special about the 11th January?  Wouldn't 1st January make more sense?

This (https://github.com/gavinandresen/bitcoinxt/commit/c81898ec46e4962daf975e352931b848026fdc34) is the fork rule change.

The max message size is increased to the maximum block size for 2 hours into the future.  This only applies to blocks though.  All other messages are limited to 2MB.

The rule is 750 out of 1000 and then a 2 week delay until activation but not before Jan 11th.

The version is 0x20000004, so I guess that is to allow another soft fork to be run at the same time.  It has some bitmask based stuff.

It seems complex to have to store the moment that the fork activates.  Even if it activates late, using the default start time for the doublings shouldn't be that big a deal.

It says doubling every 2 years for 2 years. so It will double 9 times.
8*2^9=2^12=4096 mb!!!!!!!
In 21 years from now bitcoin blocksize will be measured in petabytes.
GREAT! Let's hope thechnology advances quick enough, or we will see our
coins in a cryptocurrency museum.

What does it mean ? It will keep on growing like 8, 16, 32, 64, 128, 256, 512, 1024...

That means we are going to have 1GB block limit by 2030 on XTcoin ?

Awesome :-*

It has a max of 10 doublings, so 8GB blocks in 2036.  It depends on how fast internet bandwidth (and disk space) increases.  It is possible that we will all have fiber to the home at that point.

Second, it is possible to use a soft fork to reduce the rate at which blocks double.

A tribute to the republican marches (https://en.wikipedia.org/wiki/Republican_marches) supporting freedom of speech ? ;)

On 1st January everyone is drunk.

There is nobody present to fix the problems due to the fork.

That's when all the hilarity will ensue, and those of us that aren't using XT can drink more shots and enjoy the show.  :P

That's quite interesting :)


Awesome! Every vote counts :)

Wow, I new that XT was a fork that was for the block-size increase, but I had no idea it was doing a successive increase ever 2 years.  That seems wildly unnecessary to me and it makes me a lot more skeptical of XT than I thought I was.  Why on earth would we need 8GBs of transactions ever 10 minutes?  If everyone on earth was sending a bitcoin transaction every 10 minutes would we even need blocks this big for that?  And surely that's never going to happen.  Even if bitcoin was the only money on earth, not everyone would be exchanging it every 10 minutes.  Geezus, I often go for days without spending a dime, and I know I'm not the only one.

> Wow, I new that XT

So are you new to Bitcoin too?

> Why on earth would we need 8GBs of transactions ever 10 minutes?

People need. Maybe you don't. You can ask the same silly question about why human population is so large? Moreover, 8GB is a limit, not effective block size. If nobody uses Bitcoin, effective bitcoin block size will be closed to 0.

This is great. I should be spinning some XT nodes soon. I read that the blocks won't start growing larger immediately. Any idea when the larger blocks will go into effect?

Typos happen dude.  Maybe not to perfect people like you clearly understand everything, but for normal, fallible humans like me, typos happen.You can call the question silly or stupid, but it would have been more helpful if you'd used your omniscience to demonstrate why the qustion is silly.  My (probably wrong) estimation was that 8GB per block is waaaaay more transactions than the earth's population of humans could need.  If you could just take a little time to address that with something less terse than "people need", I think it'd be more convincing.

Also, as I'm sure someone with a god-like intelligence like you is aware, miners need fees---especially once the block-rewards are phased out.  Miners suggeerst that block-size limits create scarcity which drives up fees.

I'm sure you're completely correct  and I'm completely idiotic, but if you could just do a little more work to show me how, then my dumbass could at least get educated instead of just shamed.  Thanks in advance!

The plan is 8MB initially and the doubling every 2 years.  By 2036, it would hit 8GB.  With an 8 billion world, that works out as 1 transaction per person every 10 mins.

That isn't completely out of the question, especially if algorithms are making lots of trades.

It does seem a lot for the settlement/core system.

If Bitcoin becomes the "internet of money" then there's going to be a lot of automated services running on top of Bitcoin.

This also leaves room for all kinds of stuff that none of us can predict. It also leaves room for a giant chunk of humanity.

Think of it this way, it's better to have way more capacity than too little. We don't want blocks completely full for very long spans of time.

@TierNolan, I'm pretty sure I agree with you.  You seem to be echoing my skepticism about implementing something like this at this moment.  If there's really such a case as 1 transaction per person per ten minutes in 20 years, surely that's something we might want to address when, say, 1Mb blocks actually are getting full.

@humanitee I agree there's a lot that might happen that we can't predict.  But I guess I'm sorta in a state of shock to find out that XT is about pushing the block size to 8GB---wow, I thought 20MB was controversial.  I'd be for an increase to 20MB but this increase to 8GB seems a little, idunno, outlandish.

I think the decision should be made earlier than necessary.  The ideal would be finishing this discussion two years ago.  

They could have said that they will make the decision by the end of 2013 and have it take effect on the end of 2015 (assuming some kind of compromise).

January 2016 could still have been the switch point, but there would have been lots of time for people to upgrade.

The practical problem is that it is easy to say we should spend more time discussing things and that is what people did.  It is hard to get a decision when the problem is years away.

At this point, the decision has to be made and there is no clean way to make it.  The only option left is one that is risky all on its own (a contentious hard fork).

Increasing the size of the blocks could damage bitcoin, but not doing it could also damage things.  There is a simple disagreement about which is the greater threat to bitcoin and both sides are willing to risk the (potential) chaos of a contentious hard fork due to the risk as they see it.


It is an increase to 8GB over 20 years, which is different.  In 2036, bandwidth to the home could be high enough to handle it.

I think overestimating things is better than under estimating.  The block size limit is the maximum the blocks can be.  Miners can still set it lower by soft fork.

The reason to have it increase over time is so that new hard forks aren't needed every year.

8GB is about 1.5 tx per person per day, assuming 250bytes/tx and 7 billion people

Thanks for offering the numbers on this.  I just want to add that while we don't know what will happen with bitcoin in the next 20 years, I think everyone agrees that the idea that the world's population is going to remain flat is very unlikely.  Looks like US Census Beaureau and United Nations estimate 8.6Billion and 8.7Billion (respectively).  So, I guess that maybe it's less than 1.5 per person per day.  Is there anyone else here who thinks that the idea that every person on earth is going to send 1 Bitcoin transaction per day is a little, erm, ambitious?

I'm sure it's been talked about somewhere, but I haven't seen any details on it, but I'm curiuos why no one is pushing some kind of dynamic block size which is calculated based on the transaction volume.  We readjust difficulty to maintain a 10 minute block time.  Why shouldn't block-size be reajusted to maintain an average conf-time for a well-formed transaction with a given fee rate?

You should create a fork to implement that. It's the right thing to do when there's a disagreement, isn't it?

Ha, I know sarcasm is hard to detect on the internet, but I think I got that one.  Anyway, I'm more curious if this has been seriously proposed by someone who got more technical background that me.  It seems like much of the other parameters of the network are adjusted dynamically based on usage so I'm wondering if there's some obvious reason why block-size shouldn't be.

I went with 1 byte per transaction.  That's what I get for doing the maths to quickly.

I've seen dynamic scaling proposed on some places. A quick search reveals this:

http://www.age-of-bitcoin.com/dynamic-block-size-cap-scaling/

I've also seen it on reddit, but I'm not finding it right now...

forking bitcoin on the same blockchain is going to cause many problems.

you will end up with bitcoin and bitcoin xt, confusing many new users of bitcoin and cause the price of bitcoin to drop due to double spends.

a better idea is that bitcoin xt uses its own blockchain like all the other alt-coins, it will end up with a cleaner implementation and it will be more secure than the  plan on putting checks and rejected longer blocks just because they use 1MB blocks.

due to this the bitcoin price will most likely drop since confidence is lost.

The more we centralize bitcoin the closer  it will be to self destruction, we have to do the opposite,  decentralize as much as possible.

at 1MB block the database is over 30GB, at 20MB the database will grow to such huge proportions that it will be centralized, not only that but the idea of miner fees was to secure the network once the block gets reduced by half every 4 years, so in the long run there is no block reward only miners fees, by increasing the cost of maintaining the database, and with the reduction on miners fees the network will be insecure in the long run.

It is best to think of bitcoin as gold, as Andreas once said if the transaction is small there is no need to wait for a transaction confirmation, and it is large then you wait for the added security that the confirmations provide.

Bitcoin as of now works fine, and most likely will work forever, also a fork sends a bad precedent that things can change, politicians change the rules of the game frequently that is why bitcoin is superior to fiat currencies, if that confidence is lost bitcoin will suffer.

In brief:
Centralization --> road to failure.
Decentralization --> road to success.

If the plan is for bitcoin to be used in third world countries, where disk space and bandwidth are very expensive, it is best to stick with 1 MB blocks, and let some other alt currency fill the gap for tiny transactions if confirmations are essential, such as litecoin, or darkcoin (dash).

in the non digital world you have silver and gold, and there is a reason for that, gold is normally used for larger purchases, in a similar analogy bitcoin is like gold as litecoin or dash are like silver.

Not raising the blockchain limit to a reasonable size will also cause many problems. I personally believe the long term effects of 1MB blocks far outweighs any fragmentation risks with a Xt hard fork, assuming 75% miner supermajority.

There is no need to let 'alt coins' take any transactions from bitcoin. The analogy of Bitcoin being gold is misguided, as bitcoin isn't just gold. It can be gold, silver, copper, and diamond, at the same time.

Just raising the block size limit without including measures to mitigate unwanted effects will also cause problems.

This problem needs bigger blocks AND redesign of the incentives to create a block of a given size. Even Gavin's more simplistic proposal does not simply change one line of code from "MAXBLOCKSIZE=1MB" to "MAXBLOCKSIZE=8MB", yet everyone who argues in favour of it implies that the block size is all that matters.

Like what? I used to think raising the block size was a good idea, and that it would be continually done to accommodate a wider user base, but over time I've learned that keeping blocks too small is much less dangerous than making blocks too big, and there's plenty of evidence to suggest that blocks are too big today.
I've also realized that Bitcoin is not, cannot, and should not, be designed to compete with centralized payment processors either now or at any time in the future. Given that the biggest argument for increasing block sizes is to do just that, I've become very skeptical about not only this change, but of the general ideology of a small proportion of core developers and a large proportion of the community.

Seems as though Gavin is always the one proposing ideas and then have all the armchair idealists bitching about it.

Fork the Bitcoin and give it larger Blocks, this solution for doubling of the Block sizes every couple years will be just fine and will give the breathing room to make further changes. To those that believe that Bitcoin should remain the same as it was originally designed need to pull their head out of the sand, tech should never remain the same and should ALWAYS be changing. It does not make Bitcoin more centralized by forking it, centralization is a natural tendency of decentralized systems because people are lazy and want everyone else to make the decisions for them and then bitch about whatever the solution is going to be without coming up with a better one.

Bitcoin is at breaking point and if it does not atleast get larger Block sizes within 1 year it will not function.

I wonder how many people realize that "originally" the maximum block size was approximately 32 MB.  It was reduced to 1 MB in July 2010.

Anyone that wants bitcoin to "remain the same as it was originally designed" should be demanding a 32 MB limit on the size of a block.

Actually I did not know this but I do like the idea of doubling the Block sizes every couple years because it will give lots of leg room to make improvements and possibly other changes. I think they should start with 4mb instead of 8mb, seems like a bit much to begin with and allow for the caps to be tested as it begins to hit capacity every couple years although I can also see why they would start with 8mb Blocks because with 8 MB doubling every 2 years you would never be hitting capacity.

If by "armchair idealists" you mean "core developer pragmatists" then yes, otherwise no.

You make it sound like you never want blocks to be full, if that's the case what are you suggesting is going to fund the network when inflation stops?

Who ever argued that they don't want to see Bitcoin change just because they don't like change or because Bitcoin is perfect? I haven't seen that argument anywhere. I also disagree that "tech" should "always" be "changing", without some heavy qualifiers.

There are lots of causes for centralization, and even different types of centralization. "Laziness" is typically a driver of decentralization, actually.

I'm hearing the sirens, but I'm not seeing the threat.

Right but you basically just disagreed without any real points as to what you would change about it to make it better which is by my definition of an armchair idealist. You disagree without providing any alternative solution thus your arguement has no merit.

This is entertaining. Are you saying that any march is necessarily forward?

Emphasis mine.

When you say you want a "solution", what is the problem you're referring to?

All the recent transaction volume has been stress testing, not real volume. And all it proved was that the network functions fine under that load. More expensively, or slower, but it functions fine.

So the onus is, in fact, on you to prove your predicate that the system really is about to disintegrate under strain, as that's what your actual argument depends on. Reality disagrees, bitcoin is still running, and the impact was small.

I wasn't talking about the stress testing but I think it has been quite positive in that miners shifted pools when the simulated attack was happening. Sure it would be ok for now but another year or so most all transactions would hit the limit so the network needs atleast a larger sized Blocksize in the near term to be able to kick the can down the road and not be forced to make hasty moves and have people shut out for hours and hours over not knowing what the appropriate fee would be. You said the network performed just fine, I disagree because there were many many people who had their transactions delayed by hours during that time.

Well, there was no evidence of "breaking" as you put it, either before, during or after any of the stress tests, so you're going to have to attribute this supposed malfunction to some event or time period.


Wrong, it's supposed to create a market for transaction clearing times. So much else also needs changing to make that work better, but it's like someone said above: what do you think happens when the miners are mining nothing but fees? What happened in that stress test is what normal everyday fee pricing decisions will feel like in a mature bitcoin system.

Right, so that means at peak times it would cost a few dollars to send a transaction in order for it to be queued for delivery in a short enough period of time in which case the price of bitcoin could not move higher because transaction fees would be too high so people would use other Coins instead and so Bitcoin does not get used.

Still not getting proposed solutions, just more people talking problems.

Here's a solution, reset the chain (pruning) with the same balances at regular intervals (Clams style) so that way the Blocksize is never a problem, same with the size of the Blockchain, which is what people are ultimately worried about.

Which altcoin took over from bitcoin this week when the average transaction fee went up?

Litecoin

Of course Litecoin might have received a bit more traffic this week, but I think it would be hard to show that that was due to an increased avg transaction fee for bitcoin.  I mean consider that that's only really going to happen for people who have both litecoin and bitcoin wallets and some sort exchange account.  Sure, there are such people, but it's hard to believe that the majority of bitcoin users have an exchange account with bitcoin already deposited that they can withdrawal into litecoin so that they can send someone a transaction and that the person on the other end of the transaction is in the same situation (ready to receive what would have been a bitcoin payment in litecoin).

That said, I could believe that in a future where cryptocurrencies were the norm and Litecoin was nearly as popular as Bitcoin that such a usage swing based on transaction fees could occur.  But I don't think that day is here yet.

That rationale does not make sense. We are assuming that storage space will be doubling every two years but possibly this won't be true for long.

Also whats Bitcoin XT? Is it an altcoin?

It is a fork of Bitcoin Core with some features but it hard-forked which makes it kinda-altcoin. However, if majority users use it and if it becomes the larger chain, it maybe considered as main chain.

Github: https://github.com/bitcoinxt/bitcoinxt
Stackexchange: http://bitcoin.stackexchange.com/a/38181

There is no consensus on the block size increase so it won't happen. Just wait till the craze fades out.
Contrary to some beliefs around here consensus is not 50%+1

BitcoinXT didn't hard fork, nor will it deploy a hard fork automatically in it's current release.  The link at the beginning of the thread point to Gavin's development repository; the patch is not merged into the official maintained by Mike. There is no pull request. It's probably not even ready for serious testing, yet.

So please calm down and wait at least until Gavin thinks the code is ready.

What about these? Sorry, I am not a computer geek.

https://github.com/gavinandresen/bitcoinxt/commit/821e223ccc4c8ab967399371761718f1015c766b

https://github.com/gavinandresen/bitcoinxt/commit/c81898ec46e4962daf975e352931b848026fdc34

Those are only on Gavin's local repository.

The path is "gavinandresen/bitcoinxt" and it is forked from "bitcoinxt/bitcoinxt" (see the top of the page)

If Gavin wants those changes added to Bitcoin XT, he needs to submit a pull request.  The maintainer of Bitcoin XT (Mike) can then merge the changes into the master branch.  Alternatively, he could say that he wants some changes.  They are probably discussing what is required so when a PR is submitted, it will mostly comply with the requirements.

You mean an ostensible "75%."  In reality, it would be lower.  BIP66 thought it had "95%" support, which in reality turned out to be 64%.

The more bloated the block, the more likely an empty one will be produced while new tx are verified (which defeats the purpose).

HearnCoin is rubbish; it wouldn't even make a good side chain or alt.

You are right. My stupidness! Well, soon it will be hard-forked(or am I wrong?) if they want are going for block size increase and Bitcoin Core on 1MB maximum block size.



I am calm. I just misunderstood that commit. That's all.

Can you elaborate? Isn't it pretty easy to ascertain if the 95% of the previous 1000 blocks version 3, or is there any confusion here?

I think you got the instructions here: http://lifehacker.com/5853250/how-to-sound-like-you-know-what-youre-talking-about-even-when-you-dont

Nope and if you are suggesting me that, I am rejecting it.

If you think this is bad:

https://www.reddit.com/r/Bitcoin/comments/3c2cfd/psa_f2pool_is_mining_invalid_blocks/csrumgv?context=3

wait until the Gavinistas attempt their contentious fork with an ostensible (and much lower) "75%" of the network...   :D

"Gavinistas" is my new terminology to refer to the r/bitcoin crowd. +1

Actually it works the other way around. A soft fork adds limitations that make previously-valid blocks invalid, so miners who aren't enforcing _any_ limitations are effectively on the "didn't upgrade" side. But a hard fork makes blocks that were previously invalid valid, so if 75% are advertising big-block support but some miners who haven't advertised that aren't validating at all, you'll actually have more than 75% mining the big-block main chain.

PS. In reality you'll have much more than 75% advertising big-block support once the switch-over comes (if it ever does) because most miners will upgrade during the 2-week grace period rather than be left mining dead coins.

PPS. After losing money this way I doubt many miners will continue running with verification completely switched off; They have much better alternatives either by getting blocks propagated faster and mining normally or by at least verifying in parallel and giving up trying to mine on top of blocks once they've found that they're invalid.

Fair enough, but don't forget MPEX, etc. plan to sabotage any attempt to raise max_blocksize.  IE, they will falsely advertise >1MB compliance in order to (prematurely) bait the hard fork into a prearranged GavinCoin Short kill box.

As for losing money on invalid blocks, only the pool ops know exactly what strategy they're using and whether or not 'loss leader' invalid blocks are ultimately in the aggregate profitable.

This is not a serious suggestion. You'd need 25% of mining power to pull it off even if zero miners switched in the grace period, but since most of the remaining miners will switch during the grace period you need more like [conservatively] 45%. MPEX control approximately 0% of mining power, and if they were able to acquire more than 25% they could block bigger blocks the normal way by refusing to upgrade.

IMO it is not in the best interest of Bitcoin to create two camps, XT and CORE.
We need to stick together for bitcoin to succeed.

What most of the silicon valley morons in their ivory towers don't get is: when unemployment rates and inflation keep following the trends and another stockmarket crash and financial crisis happen within next decade nobody in the general population will be able to afford the bandwidth to run bitcoin.
So in a situation where people would need it it has become inaccessible due to bandwidth requirements which almost nobody will be able to meet simply because internet connection speed won't grow in times when people barely can put food on the table.

Increasing blocksize like this will be the end of bitcoin even if the fork doesn't result in instant meltdown.

Bandwidth grow will slow and because the SV guys' prediction doesn't come true bitcoin will be useless.
With increasing the blocksize like that you also accept that your coins become worthless in case either bandwidth doesn't grow as predicted or adoption doesn't grow as predicted. Effectively you tie the fate of bitcoin to the correctness of your estimates, guesses and predictions which will likely fail.

Reminder: nobody knows the future ... so you are one big parade of fails.

Except you, apparently?

This is the only thing you said that makes sense.  I agree completely.

So, if nobody knows the future, then how can you say any of the following?

Gavin and Hearn aren't silicon valley morons in ivory towers (that's just their schmaltzy marketing PR).  They're actually more like Langley/Bethesda spooks in smoke-filled back rooms.

Regardless, you are correct that it's idiotic, irresponsible, and dangerous to assume the "financial crisis is over" and, as a result, we're about to enjoy a worldwide explosion in retail bandwidth 'because NetFlix.'