How would bitcoin deal with a sudden drop in hashrate?

[betajuice]

With increased mining centralization, and so much hashpower located in particular national jurisdictions such as China, I'm concerned about the risk of a sudden drop in hashrate. There can't be a difficulty adjustment if no new blocks are being mined. Mining could be made illegal and large farms be forced to shutdown. Would node operators agree to an emergency difficuly adjustment hardfork ?

[Marcel666]

Having majority of mining power from a particular region is not a problem at all in my opinion.

I doubt this would reduce hashrate, bitcoin has survived in its early days with little of the current attention so it would adapt to any change

[figmentofmyass]

With increased mining centralization, and so much hashpower located in particular national jurisdictions such as China, I'm concerned about the risk of a sudden drop in hashrate. There can't be a difficulty adjustment if no new blocks are being mined. Mining could be made illegal and large farms be forced to shutdown. Would node operators agree to an emergency difficuly adjustment hardfork ?

even in the above case, it's not clear that no new blocks would be mined. miners are distributed all around the world. if 50% of the miners shut down, blocks would still come every 20 minutes on average, though a backlog of transactions would grow until the next (delayed) adjustment occurs.

this has been discussed before though, and apparently similar code (developed for altcoins) has been ready and well-tested for a long time. luke dashjr proposed a hard fork a couple years ago to alleviate the above risks: https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-March/012489.html

regarding whether users and node operators would agree? it's difficult to say. the very fact that it requires a hard fork could make it controversial.

[p3rk0]

Bitcoin will always have the majority of hashpower available so in that sense it won't matter at all.

[franky1]

firstly lower hash rate does not mean slower blocks

here are the reasons

1. the 20+ pools are all running their own races. with their own hashrate. if 10 pools disappeared there are still 10 pools running.

2. imagine it like a 100metre race, 20 runners. they all average 10 seconds but only 1 is declared the winner. if you shoot 10 runners.. the remaining 10 runners dont suddenly race at a 20 second average. the 100m is still completed in the same 10 second average.

3. those racist fools promoting "china is evil" have no clue. if you actually study the network. you will see there is more diversity within the pools tagged as "china"
lets take antpool. they do not use 1 coin reward address. they use a few. and if you study things more these addresses are individually managed at SEPARATE LOCATIONS in iceland, gorgia, america, mongolia and china. you will notice that some of the antpool addresses use segwit bech32 addresses and some dont. which also proves the management is independant
so its not as "china is evil" as you think. then there is slushpools that gets classed as china. but is actually managed in thailand and users are all over the world. f2pool have users around the world
so stop believing the racist rants of china owns bitcoin mining

4. if you actually check the hashrate per block as oppose to averaged day you will see even today some blocks were solved with
5exa to 35exa... meaning every day there is actually a variance of more than 50%... but you dont realise it because the charts average it out and combine data

7. if some stratum servers are taken out. you will actually see alot of farms actually pool jump. and so the remaining pools will increase the hashrate per pool and some blocks will get solved FASTER

6. in short. you wont notice it because if you take away the 'average' stats that hide the real numbers. we are already in a zone and always have been in a zone where blocks are solved with a 50% variance

[SamReomo]

With increased mining centralization, and so much hashpower located in particular national jurisdictions such as China, I'm concerned about the risk of a sudden drop in hashrate. There can't be a difficulty adjustment if no new blocks are being mined. Mining could be made illegal and large farms be forced to shutdown. Would node operators agree to an emergency difficuly adjustment hardfork ?

There will be no problem for miners as it doesn't matter if most miners are in a particular jurisdiction. The hash rate will not have any impact because of that and it won't drop anyways. New blocks will always be mined even if most of miners stop mining it.

You should not worry at all because Bitcoin if more mighty than our current understanding of it. It will rule the world of new generation and mining of it will be as important as mining of gold and other precious jewels. It will be adapted by everyone one day and yes even then it will be independent.

[pooya87]

With increased mining centralization,

wrong. there is a "decrease" in mining centralization every day.  if you search for the way hashrate was distributed back in a couple of years ago like 2013 and compare it with today you can see it clearly.

and so much hashpower located in particular national jurisdictions such as China,

partially wrong. there is a large hashrate in certain countries like China because there are mining farms there but it is not  as much as you think because what you see in those "stats" sites is the hashrate of the mining pool not the mining farm. and a mining pool is where many miners from many locations connect to.

I'm concerned about the risk of a sudden drop in hashrate. There can't be a difficulty adjustment if no new blocks are being mined. Mining could be made illegal and large farms be forced to shutdown. Would node operators agree to an emergency difficuly adjustment hardfork ?

the number of miners is too huge that shutting down one mining farm is not going to cause that much of a problem. and why would they suddenly be banned and shut down since they are perfectly legal as it is? it is like saying Microsoft may become illegal out of the blue so you can't use Windows anymore!

[Kakmakr]

With increased mining centralization, and so much hashpower located in particular national jurisdictions such as China, I'm concerned about the risk of a sudden drop in hashrate. There can't be a difficulty adjustment if no new blocks are being mined. Mining could be made illegal and large farms be forced to shutdown. Would node operators agree to an emergency difficuly adjustment hardfork ?

Bitcoin mining will never be made illegal in ALL countries in the world. The remaining miners will just keep on mining and the difficulty will drop. Even if it was made illegal, people will still mine it illegally. <We saw this with the Prohibition of alcohol for instance> 

The dropout rate <When it is banned> will not simply be a massive shutdown of all mining farms, but rather a slow dropout rate, where one farm after the other will shutdown their operation. Most of them will relocate their operation to other countries where Bitcoin mining is not banned and they will continue as normal. 

[dothebeats]

This isn't even a problem IMO since mining centralization isn't really happening though the media wants you to believe that everything is "Chinese" in terms of hash power. Also, mining couldn't be made illegal if operators acquired their machines legally, paying their taxes and doesn't use illegal power whatsoever. There simply isn't any grounds for a government to ban bitcoin mining since it might create a loophole and affect other industries.

Lastly, slower hash rate doesn't mean a slower network if there are still a lot of scattered plaers in the field. The difficulty will adjust automatically once it noticed a sudden drop in hash rate and the nodes would just need to sit back and do their thing.

[squatter]

firstly lower hash rate does not mean slower blocks

here are the reasons

1. the 20+ pools are all running their own races. with their own hashrate. if 10 pools disappeared there are still 10 pools running.

2. imagine it like a 100metre race, 20 runners. they all average 10 seconds but only 1 is declared the winner. if you shoot 10 runners.. the remaining 10 runners dont suddenly race at a 20 second average. the 100m is still completed in the same 10 second average.

That's incorrect. If hash rate drops in half, then on average, block times will double. A reduced hash rate = lower chances of finding blocks. This increases block times, which increases the time before the next difficulty adjustment.

This is why the difficulty adjustment algorithm exists at all -- to retarget block time to 10 minutes when increases or decreases in hash rate change the average block time.

Think about it. What you're saying means that if 99.9% of miners shut down, that the 0.01% hash power left can still crank out blocks every 10 minutes.

[yoseph]

It’s going to have a negative and positive effects for users of bitcoin because on hand the miners that are left are going to get a lot of money when it comes to confirming those orders and the negative side will be that users are going to pay more for transactions if they want them to confirm early.

[cizatext]

Well the hardfosk are at the controlling side of the the bitcoin mining industry and despite the fact that drop in harshrate can lead to further uncontrollable drop in the market and transactions being delayed due to over conjunction of the bitcoin network and which may lead to high fee being charged by the blockchain so we never hope for that kind of situations.

[franky1]

firstly lower hash rate does not mean slower blocks

here are the reasons

1. the 20+ pools are all running their own races. with their own hashrate. if 10 pools disappeared there are still 10 pools running.

2. imagine it like a 100metre race, 20 runners. they all average 10 seconds but only 1 is declared the winner. if you shoot 10 runners.. the remaining 10 runners dont suddenly race at a 20 second average. the 100m is still completed in the same 10 second average.

That's incorrect. If hash rate drops in half, then on average, block times will double. A reduced hash rate = lower chances of finding blocks. This increases block times, which increases the time before the next difficulty adjustment.

This is why the difficulty adjustment algorithm exists at all -- to retarget block time to 10 minutes when increases or decreases in hash rate change the average block time.

Think about it. What you're saying means that if 99.9% of miners shut down, that the 0.01% hash power left can still crank out blocks every 10 minutes.

first of all. your final sentance proves you dont understand how things work. ven though its obvious u exagerated such numbers. in any context your point would be wrong

you mind set is that if there were
20 pools of lets say 2.5exa (to total a 50exa network)
that there would become a 20 pool of 1.25exa
or there would be 10 pools of 2.5xa
the reality is that IF some people see things slow down(not much chance). they would 'pool hop' and make a scenario of 20 pools of 1.25 become 10 of 2.5
so that in a scenario of like i mentioned before a 100m race of initially 20 runners, now becomes 10 runners and all 10 runners still average 10 seconds but only one can be declared the winner
this means if there were over 100 races per day the racers actually double their chances of winning becuase there is less competition fighting over who gets to cross the finish line first

it might be worth you looking at the real data. the realtime data and not the averaged aggregated data that loses its meaning

i truly laugh at anyone that thinks because an olympic runner crosses the finish line in 10 seconds. a runner up must take 20seconds and 3rd place must take 40 seconds.. (facepalm)

[Mathias Allen]

With certain locations having increased mining activity, I don't think that'll be a big issue. As bitcoin has survived tougher conditions back in the early days, I doubt this would reduce hashrate. But, as there is no gurantees for the future, we'll see how issues in the coming future are dealt with.

[Ariella Maldonado]

Bitcoin is the most stable coin and it is backed by more than enough miners. It is an impossible scenario where mining will be illegalized and banned ALL over the world. So, there will always be miners who will keep mining. Even if the mining deos get banned, it will be the end of all crypto currency along with the BItcoin.

[florianuhlemann]

you do not take into account such a moment that with the fall the reward for the block will increase, which means that the offer will be restored

[Nikolas Brown]

I don't think there would be any problem in all the miners being in a particular jurisdiction. Hashrate is not likely to drop because of this. You don't have to worry about mining being illegal.

[Danielle Lewis]

Miner increasing isn't supposed to pressurise the bitcoin. The miner is always increasing and any currency is made for attracting more and more investors. Also, the coin is becoming more user friendly and secured these days, so it has a chance to be accepted by maximum countries, and its total worth might increase eventually.

[kryptqnick]

With increased mining centralization, and so much hashpower located in particular national jurisdictions such as China, I'm concerned about the risk of a sudden drop in hashrate. There can't be a difficulty adjustment if no new blocks are being mined. Mining could be made illegal and large farms be forced to shutdown. Would node operators agree to an emergency difficuly adjustment hardfork ?

I think it's not that hard. Some blocks will have to be mined and if half of the pools it out then it will take twice as much time (about a month, I guess), but the difficulty rate will adjust accordingly after that. Blocks will still be mined even if there is a very small amount of miners left. It will be just a matter of time when things get normal again. And I think that even a half of mining power being out at once is a very unrealistic scenario, so the bad times won't take long. Moreover, a lot of miners will probably join the network right after the difficulty rate is adjusted, since mining will become more profitable for this period of time. Everything will be balanced eventually.

[squatter]

firstly lower hash rate does not mean slower blocks

here are the reasons

1. the 20+ pools are all running their own races. with their own hashrate. if 10 pools disappeared there are still 10 pools running.

2. imagine it like a 100metre race, 20 runners. they all average 10 seconds but only 1 is declared the winner. if you shoot 10 runners.. the remaining 10 runners dont suddenly race at a 20 second average. the 100m is still completed in the same 10 second average.

That's incorrect. If hash rate drops in half, then on average, block times will double. A reduced hash rate = lower chances of finding blocks. This increases block times, which increases the time before the next difficulty adjustment.

This is why the difficulty adjustment algorithm exists at all -- to retarget block time to 10 minutes when increases or decreases in hash rate change the average block time.

Think about it. What you're saying means that if 99.9% of miners shut down, that the 0.01% hash power left can still crank out blocks every 10 minutes.

first of all. your final sentance proves you dont understand how things work. ven though its obvious u exagerated such numbers. in any context your point would be wrong

No, it proves you don't understand how things work. You literally said "if you shoot 10 runners.. the remaining 10 runners dont suddenly race at a 20 second average. the 100m is still completed in the same 10 second average." That's the same exact thing!

You're saying that if hash rate drops in half sans difficulty adjustment, that block time will remain unchanged. That's absurd and shows a complete lack of understanding of how difficulty works.

Why is there a difficulty adjustment algorithm that retargets block time to 10 minutes? According to you, block time is always magically 10 minutes, regardless of hash power or difficulty.

so that in a scenario of like i mentioned before a 100m race of initially 20 runners, now becomes 10 runners and all 10 runners still average 10 seconds but only one can be declared the winner
this means if there were over 100 races per day the racers actually double their chances of winning becuase there is less competition fighting over who gets to cross the finish line first

That's only relative to other miners. You're not accounting for the actual likelihood of blocks being mined.

If difficulty remains the same and computing power drops in half, the chances that any block will be found across the network will drop in half. It doesn't matter if there is "less competition" because difficulty hasn't dropped at all. It hasn't become any easier to find blocks, but half the miners are gone.