Eligius: 0% Fee BTC, 105% PPS NMC, No registration, CPPSRB

[anth0ny]

I appreciate the answers, but the "increases security" reason seems like nonsense to me.  The purpose of the block is not to provide security, it is to record transactions.

No. That isn't right. Even an empty block helps people out. If nothing else, the empty block makes the coinbase transaction from 120 blocks previous become spendable. In practice, the empty block brings all those 5-confirmation transactions up to 6 confirmations (and 2-confirmation transactions up to 3 confirmations, etc.) The presence of the empty block makes transactions confirm faster than they would have if the empty block weren't there.

A full block is better than an empty block. But an empty block is better than nothing. (And a block at the same height and roughly the same time as someone else's partially propagated block, which temporarily splits the network into two chains of equal height, is significantly worse than nothing.)

Ideally, transaction fees probably wouldn't go solely to the block in which they were located, but would go to that block and future blocks which build upon them (maybe in a declining way like 50% to the first block, 25% to the second block, 13% to the third block....I don't know as I haven't fully thought about it). Right now it doesn't particularly matter, as the transaction fees are small compared to the block reward. But in the future when there are no block rewards at all, just transaction fees, there might be problems due to this (if someone puts an especially large fee on a transaction, there might be an incentive for miners to "steal" that transaction fee by orphaning the block which includes it instead of building upon the block which includes it). Fortunately there are many years before this will become an issue.

Yes, the empty block is followed by a block of transactions, but I still contend that the empty block is worthless to the network.

In addition to the direct benefits of faster confirmations and faster spending of generated coins, think about how the inclusion or non-inclusion of the empty block affects someone who is performing so-called "selfish mining" or some other sort of block delaying attack.

[Mikestang]

Even an empty block helps people out. If nothing else, the empty block makes the coinbase transaction from 120 blocks previous become spendable. In practice, the empty block brings all those 5-confirmation transactions up to 6 confirmations (and 2-confirmation transactions up to 3 confirmations, etc.) The presence of the empty block makes transactions confirm faster than they would have if the empty block weren't there.

There is no need to try and "speed up" transactions artificially.  Everything positive you said about an empty block applies to a block full of transaction, only the full block provided worth to the network because it contains transactions, which is a block's purpose.  You even admit in your post that a full block is better than an empty block.  And I still do not see any benefit from an empty block, but again I appreciate the attempt at explaining to me.

[Luke-Jr]

I appreciate the answers, but the "increases security" reason seems like nonsense to me.  The purpose of the block is not to provide security, it is to record transactions.  Security is inherent in the way the network was designed.

No, any node can arbitrarily record any transactions it wants without miners.
Mining's primary purpose is to provide security for them.

"Empty" blocks are not really empty either: they still include every transaction mined by the prior blocks.
And since 1 block is not sufficient to confirm a transaction, it's really the block 5 down the chain which is beneficial to the transactions in the block mined anyway.

[jonnybravo0311]

No, any node can arbitrarily record any transactions it wants without miners.
Mining's primary purpose is to provide security for them.

I can write a transaction down on a piece of paper and leave it on my desk, too.  It means absolutely squat until such time that some miner somewhere provides a block that is added to the public ledger known as the blockchain.  Mining's primary purpose is to confirm the validity of transactions by adding them to the ledger through proof of work hashing.  If my transaction never makes it into that ledger, it may as well never have happened.  Expand upon that and see what happens.  A whole bunch of blocks created doing nothing but generating block rewards that can never be used because no transactions are ever included in the blocks.  Extreme case?  Absolutely.

"Empty" blocks are not really empty either: they still include every transaction mined by the prior blocks.
And since 1 block is not sufficient to confirm a transaction, it's really the block 5 down the chain which is beneficial to the transactions in the block mined anyway.

No, empty blocks do not include every transaction mined by the prior blocks, they include a way to get to a parent block.  That block might have the transaction, or it might not... but it also includes a way to get to its parent block and so on back to the genesis block.

[Luke-Jr]

I can write a transaction down on a piece of paper and leave it on my desk, too.  It means absolutely squat until such time that some miner somewhere provides a block that is added to the public ledger known as the blockchain.  Mining's primary purpose is to confirm the validity of transactions by adding them to the ledger through proof of work hashing.  If my transaction never makes it into that ledger, it may as well never have happened.

No, that transaction remains perfectly valid as long as the sender is honest. The blockchain is only needed to provide security against dishonest senders.

"Empty" blocks are not really empty either: they still include every transaction mined by the prior blocks.
And since 1 block is not sufficient to confirm a transaction, it's really the block 5 down the chain which is beneficial to the transactions in the block mined anyway.

No, empty blocks do not include every transaction mined by the prior blocks, they include a way to get to a parent block.

Which is the same as any new transactions in the block.

[jonnybravo0311]

No, that transaction remains perfectly valid as long as the sender is honest. The blockchain is only needed to provide security against dishonest senders.

I agree that the transaction is perfectly valid.  However, valid or not, until that transaction is recorded and confirmed in the public ledger, the transfer of coin is not legitimized.  An empty block certainly helps to ensure that malicious activity becomes that much harder to perpetrate on the previous blocks, but it does nothing for all of those transactions out there waiting to be added to the chain.  Now, if there simply are no transactions to be included, then by all means, add empty blocks.

Which is the same as any new transactions in the block.

Not sure I follow here... I've added an empty block to the chain (well, there's at least 1 transaction because of the generated coins).  That block has no other transaction.  It does, however, know its parent.  Are you stating that because I know my lineage until genesis, that's equivalent to having all transactions in every block?  I'd argue that if this were the case, then every block would be larger than it's predecessor.  Genesis would be size (n), block 1 would be (n + m), block 2 would be (n + m + x) and so on... obviously that's not true.  I'll agree that every block has knowledge of its own transactions and a way to get to all previous transactions, but not that every block has every transaction .

[Mikestang]

I'll source the Bitcoin Wiki for the definition of mining, https://en.bitcoin.it/wiki/Mining.  The very first sentance of the page states:

Mining is the process of adding transaction records to Bitcoin's public ledger of past transactions.

Here's a few other mining definitions (emphasis added by me):

https://bitcoin.org/en/faq#what-is-bitcoin-mining

Mining is the process of spending computing power to process transactions, secure the network, and keep everyone in the system synchronized together.

Mining software listens for transactions broadcast through the peer-to-peer network and performs appropriate tasks to process and confirm these transactions.

http://www.investopedia.com/terms/b/bitcoin-mining.asp

Bitcoin mining is the process by which transactions are verified and added to the public ledger, known as the block chain, and also the means through which new bitcoin are released.

http://whatis.techtarget.com/definition/Bitcoin-mining

Bitcoin mining is the processing of transactions in the digital currency system, in which the records of current Bitcoin transactions, known as a blocks, are added to the record of past transactions, known as the block chain.

http://en.wikipedia.org/wiki/Bitcoin#Mining

Mining is a record-keeping service.[note 9] Miners keep the block chain consistent, complete, and unalterable by repeatedly verifying and collecting newly broadcast transactions into a new group of transactions called a block.

Therefore, I contend that if you're not adding transactions to the blockchain (i.e. solving an empty block) then you are not mining.

[jonnybravo0311]

I'll source the Bitcoin Wiki for the definition of mining, https://en.bitcoin.it/wiki/Mining.  The very first sentance of the page states:

Mining is the process of adding transaction records to Bitcoin's public ledger of past transactions.

Therefore, if you're not adding transactions to the blockchain (i.e. solving an empty block) then you are not mining.

Here's a few other mining definitions (emphasis added by me):

https://bitcoin.org/en/faq#what-is-bitcoin-mining

Mining is the process of spending computing power to process transactions, secure the network, and keep everyone in the system synchronized together.

http://www.investopedia.com/terms/b/bitcoin-mining.asp

Bitcoin mining is the process by which transactions are verified and added to the public ledger, known as the block chain, and also the means through which new bitcoin are released.

http://whatis.techtarget.com/definition/Bitcoin-mining

Bitcoin mining is the processing of transactions in the digital currency system, in which the records of current Bitcoin transactions, known as a blocks, are added to the record of past transactions, known as the block chain.

http://en.wikipedia.org/wiki/Bitcoin#Mining

Mining is a record-keeping service.[note 9] Miners keep the block chain consistent, complete, and unalterable by repeatedly verifying and collecting newly broadcast transactions into a new group of transactions called a block.

Empty blocks are not mining.

Until the block rewards subsidy goes away, an empty block still technically has one transaction: the coinbase which distributes the generated coins from the block reward.

So, while it isn't adding any value by including other transactions, it does, indeed technically fit the definition of mining.

[Mikestang]

Until the block rewards subsidy goes away, an empty block still technically has one transaction: the coinbase which distributes the generated coins from the block reward.

So, while it isn't adding any value by including other transactions, it does, indeed technically fit the definition of mining.

Every single definition of mining states "transactions", plural.  Nothing is confirmed in an empty block, it does not meet the definition.  Seems to me the empty block thing is a huge oversight, and that empty blocks should not be valid and the network should reject them.  The only block that should have been considered valid with a single transaction generating coins was the genesis block.

Has there been any analysis of an "empty block attack"?  Imagine what would happen if an inordinate number of empty blocks were solved and submitted in succession?  Bitcoin would effectively cease functioning.

[jonnybravo0311]

Until the block rewards subsidy goes away, an empty block still technically has one transaction: the coinbase which distributes the generated coins from the block reward.

So, while it isn't adding any value by including other transactions, it does, indeed technically fit the definition of mining.

Every single definition of mining states "transactions", plural.  Nothing is confirmed in an empty block, it does not meet the definition.  Seems to me the empty block thing is a huge oversight, and that empty blocks should not be valid and the network should reject them.  The only block that should have been considered valid with a single transaction generating coins was the genesis block.

I read the usage of the plural transactions to be a set from one to many.  I also think that empty blocks do indeed serve a purpose if there are no other transactions to be processed.  However, I am in complete agreement that if there are transactions to be processed, any created block should include any/all of those transactions and not ignore them outright just for the sake of adding a block to the chain, or keeping miners from stale shares, or whatever else has been given as a reason.

The kind of validation you're proposing would be rather daunting.  It would require every node have knowledge that when the block they're verifying was created there were in fact transactions that could have been included into that block.  You can't just blindly reject all blocks with only a single coinbase transaction, because it could very well be that there really were no transactions to include (albeit extremely unlikely).

[Mikestang]

I suspect (with a very high degree of certainty) that the bitcoin network has grown well beyond the point that we could ever expect a 10 minute period to elapse without a singular transaction occurring somewhere in the world.

[jonnybravo0311]

I suspect (with a very high degree of certainty) that the bitcoin network has grown well beyond the point that we could ever expect a 10 minute period to elapse without a singular transaction occurring somewhere in the world.

Of that I have no doubt; however, blocks are found within seconds sometimes.  If I remember correctly, AntPool had a 3 second back-to-back block just a few days ago.  I also remember there was a very close (within seconds) back-to-back block by p2pool.  This doesn't include blocks found and submitted by miners on different pools that occur within seconds either.

[anth0ny]

Even an empty block helps people out. If nothing else, the empty block makes the coinbase transaction from 120 blocks previous become spendable. In practice, the empty block brings all those 5-confirmation transactions up to 6 confirmations (and 2-confirmation transactions up to 3 confirmations, etc.) The presence of the empty block makes transactions confirm faster than they would have if the empty block weren't there.

There is no need to try and "speed up" transactions artificially.

Where "artificially" means what, exactly? Everything we're doing is artificial.

Everything positive you said about an empty block applies to a block full of transaction, only the full block provided worth to the network because it contains transactions, which is a block's purpose.  You even admit in your post that a full block is better than an empty block.

Yep. A full block is better than an empty block. But the choice isn't between a full block and an empty block, it's between an empty block and a stale block.

And I still do not see any benefit from an empty block, but again I appreciate the attempt at explaining to me.

Compared to nothing? The benefits are the ones I listed, including speeding up the confirmation of transactions.

[anth0ny]

Has there been any analysis of an "empty block attack"?  Imagine what would happen if an inordinate number of empty blocks were solved and submitted in succession?  Bitcoin would effectively cease functioning.

Someone (or a group of people working in concert) who can solve and submit an inordinate number of blocks (of any type) in succession can do bad things. This is a well-known problem for which there is no possible solution (at least no solution within the concept of having a decentralized proof of work blockchain).

Fortunately, in order to submit an inordinate number of blocks in succession with any significant probability, you have to have a lot of "mining power" (51% would definitely do it; maybe 33 1/3% under the right situations; probably somewhere in between the two under less "ideal" situations).

Seems to me the empty block thing is a huge oversight, and that empty blocks should not be valid and the network should reject them.

It's trivial to add one (or any number of) useless spam transactions to a block. If you're trying to save network bandwidth you could even calculate the spam transactions based on a formula, so you don't have to send the actual transaction content over the network. So rejecting empty blocks wouldn't add any security, and would really just add complications to the client. It could also potentially make Sybil attacks slightly easier (all you have to do to stop a miner from mining is stop them from getting new transactions, you don't have to shut down their network connection entirely).

You could have a rule where every block must have at least a certain number of bitcoin-days destroyed. But that would have its plusses and minuses. Something for an altcoin to consider (especially if you added something fun like negative transaction fees for "high priority" transactions), but not something that's necessary for bitcoin.

[Luke-Jr]

Mostly the same information I said here, but FWIW: http://www.reddit.com/r/Bitcoin/comments/36qje1/why_can_a_block_have_only_1_transaction/crgtdxk

Which is the same as any new transactions in the block.

Not sure I follow here... I've added an empty block to the chain (well, there's at least 1 transaction because of the generated coins).  That block has no other transaction.  It does, however, know its parent.  Are you stating that because I know my lineage until genesis, that's equivalent to having all transactions in every block?  I'd argue that if this were the case, then every block would be larger than it's predecessor.  Genesis would be size (n), block 1 would be (n + m), block 2 would be (n + m + x) and so on... obviously that's not true.  I'll agree that every block has knowledge of its own transactions and a way to get to all previous transactions, but not that every block has every transaction .

I don't know if I am capable of explaining this without explaining the Bitcoin protocol (and there are plenty of references you could read on it already). Blocks have two pointers, one to all past blocks/transactions, and one to new transactions. Both of these are just pointers, however. When people talk about block size, they are including all the new transactions, but that's just a matter of abstraction.

[Biomech]

Wow, that was a lot of to-do about nothing... Look at any block explorer and tell me how many "empty" blocks you find. I've never seen one, though I know they can theoretically exist. Just because of this conversation, I think I'll pay more attention to it. but seriously?

[bomberb17]

What's going on with this pool's "luck"??
This is ridiculous..
Can someone post the average luck for the last 30 days?

[chalkboard17]

What's going on with this pool's "luck"??
This is ridiculous..
Can someone post the average luck for the last 30 days?

Agree, this is also getting me thinking. I only checked last weeks but this entire time ghash had nearly same hashrate the entire time but mined 3 times more blocks.

[MaximeAD]

What's going on with this pool's "luck"??
This is ridiculous..
Can someone post the average luck for the last 30 days?

Statistical part
I think I had about 80% shares rewarded on April 30. I still had 80% shares rewarded on May 31st. We can then grossly estimate the pool luck was 80% for May 2015.

Is it unexpected? Let's see...

Today, the reported hashing power is 6.7 PH/s. Assuming difficulty was at current rate for this month and hashrate has not moved for simplification, it means there should have been about 86 blocks founds. The estimation of the pool luck tells us that 80% of this expected value was found -> 67 blocks.

Is it statistically surprising? What are the odds that 67 blocks or less are found with what we know?

The number of blocks found can be modelled with a Poisson Distribution with mean 86. A quick Excel calculation tells me that with assumptions told in this post, there was about a 8% probability to find 67 blocks or less for the month of may. Not that surprising that it can happen.. That's the kind of variation you can expect with the size of the pool.

Let's remember that we are also more sensitive to the bad luck of the pool versus its good luck which can bias our view.

Conclusion
If you want less variation in your reward, you should seek bigger pool. https://blockchain.info/pools . You can also put your hashing power on many pools which will have for effect to decrease your variance.

For now, all my hashing power is on Eligius. I tried BTCGuild, Ghash, Antpool... But what is important for me is the transparency of the pool and the expected reward value (No fees). This is what you have with Eligius and I'm a big fan of the pool.

I find it unfortunate that it shrinks in hashing power since it increases variance, but the only thing I can do is keep my hashing power there...!

[bhanu545]

my 128,256 seconds hashrate does not show anything but zero since 30min. whats the problem?