Decentralizing ming
8 messages, 17 to 19 Jul 2014. Started by Jeff Garzik.
Jeff Garzik (3), Mike Hearn (2), Emin Gün Sirer (2), slush
Define acceptable. The 40% thing is marketing and a temporary solution. And people come down on both sides of whether or not marketing "40%" is a good idea.
I think it is a baby step that is moving in the right direction. You want the numbers and sentiment moving in that direction (down, versus "own the market! </IPO>").
The more critical piece is fleshing out the various proposals and technical solutions for decentralized transaction selection and other aspects of SPOF-proofing mining.
Historical note: On one hand, Satoshi seemed to dislike the early emergence of GPU mining pools quite a bit. On the other hand, Satoshi noted that the network would probably devolve down to a few big players if we ever reached VISA/MC transaction levels. Satoshi clearly never figured this part out :)
Today, there is consensus on the need for a "keep bitcoin free and open" technical solution, but it remains to be seen how much we engineers can really do to make life fair. Making transaction selection a bit more independent from hashpower seems one step. There are several other proposals floating about.
On Thu, Jul 17, 2014 at 6:14 PM, Jeff Garzik <jgarzik@bitpay•com> wrote:
Quoted text (3 lines)
> Historical note: On one hand, Satoshi seemed to dislike the early > emergence of GPU mining pools quite a bit. >
To my knowledge, Satoshi left the project before mining pools got a traction.
slush
Jeff, I think the message you're replying to got clipped.
Satoshi's only comment AFAIK on the topic of GPU mining was to wish for a gentlemen's agreement to postpone it as long as possible, to help make sure the distribution of coins was as even as possible. Indeed this predated pooled mining.
Oops, sorry, I see the subject line changed. This is what I get for working down the thread list top to bottom :)
I think the best path forward now is to finish off getblocktemplate support in the various tools so it's possible to pool for payout purposes without giving up control of block creation modulo the coinbase. Combined with the recent sipa performance enhancing goodness, it would hopefully persuade some non-trivial chunk of hashpower to go back to running their own node and start the process of turning pools merely into payout trackers rather than block selectors.
On Fri, Jul 18, 2014 at 12:41 PM, Mike Hearn <mike@plan99•net> wrote:
Quoted text (8 lines)
> Jeff, I think the message you're replying to got clipped. > > Satoshi's only comment AFAIK on the topic of GPU mining was to wish for a > gentlemen's agreement to postpone it as long as possible, to help make sure > the distribution of coins was as even as possible. Indeed this predated > pooled mining. > >
Before they got traction, yes. But he projected a bit, as anyone could, to see the trend.
On Thu, Jul 17, 2014 at 1:22 PM, slush <slush@centrum•cz> wrote:
Quoted text (11 lines)
> > On Thu, Jul 17, 2014 at 6:14 PM, Jeff Garzik <jgarzik@bitpay•com> wrote: >> >> Historical note: On one hand, Satoshi seemed to dislike the early >> emergence of GPU mining pools quite a bit. > > > To my knowledge, Satoshi left the project before mining pools got a > traction. > > slush
Yes. That, and several other things. If you can figure out how to propagate a block without re-propagating all the transactions everyone already has, you address the large-blocks-slower-to-relay problem, and additionally create an incentive for miners to mine blocks consisting of publicly broadcast transactions (versus a bunch of secret ones mined with secret agreements).
Democratizing transaction selection takes a bit of power away from the miners and gives it back to the network at large. GBT is another piece of that puzzle.
On Fri, Jul 18, 2014 at 6:43 AM, Mike Hearn <mike@plan99•net> wrote:
Quoted text (22 lines)
> Oops, sorry, I see the subject line changed. This is what I get for working > down the thread list top to bottom :) > > I think the best path forward now is to finish off getblocktemplate support > in the various tools so it's possible to pool for payout purposes without > giving up control of block creation modulo the coinbase. Combined with the > recent sipa performance enhancing goodness, it would hopefully persuade some > non-trivial chunk of hashpower to go back to running their own node and > start the process of turning pools merely into payout trackers rather than > block selectors. > > > On Fri, Jul 18, 2014 at 12:41 PM, Mike Hearn <mike@plan99•net> wrote: >> >> Jeff, I think the message you're replying to got clipped. >> >> Satoshi's only comment AFAIK on the topic of GPU mining was to wish for a >> gentlemen's agreement to postpone it as long as possible, to help make sure >> the distribution of coins was as even as possible. Indeed this predated >> pooled mining. >> >
I thought I'd chime in and point out some research results that might help. Even if they don't, there is a cool underlying technique that some of you might find interesting.
The problem being tackled here is very similar to "set reconciliation," where peer A thinks that the set of transactions that should be in the block is S_A, and peer B has actually included set S_B, and S_A and S_B are expected to not differ much. Ideally, one would like the communication complexity between A and B to be O(delta), not O(S_B) as it is right now. And ideally, one would like B to send a single message to A, and for A to figure out the difference between the two sets, without any lengthy back and forth communication. In essence, I would like to give you some magical packet that is pretty small and communicates just the delta between what you and I know.
This paper from Cornell describes a scheme for achieving this: Yaron Minsky, Ari Trachtenberg, Richard Zippel: Set reconciliation with nearly optimal communication complexity. IEEE Transactions on Information Theory 49(9): 2213-2218 (2003) http://ipsit.bu.edu/documents/ieee-it3-web.pdf
Those of you looking for a TL;DR should read the intro and then skip to page 8 for the example. The underlying trick is very cool, comes from the peer-to-peer/gossip literature, and it is underused. It'd be really cool if it could be applied to this problem to reduce the size of the packets.
This approach has three benefits over the Bloom filter approach (if I understand the Bloom filter idea correctly):
(1) Bloom filters require packets that are still O(S_A),
(2) Bloom filters are probabilistic, so require extra complications when there is a hash collision. In the worst case, A might get confused about which transaction B actually included, which would lead to a fork. (I am not sure if I followed the Bloom filter idea fully -- this may not happen with the proposal, but it's a possibility with a naive Bloom filter implementation)
(3) Bloom filters are interactive, so when A detects that B has included some transactions that A does not know about, it has to send a message to figure out what those transactions are.
Set reconciliation is O(delta), non-probabilistic, and non-interactive. The naive version requires that one have some idea of the size of the delta, but I think the paper has some discussion of how to handle the delta estimate.
I have not gone through the full exercise of actually applying this trick to the Bitcoin p2p protocol yet, but wanted to draw your attention to it. If someone is interested in applying this stuff to Bitcoin, I'd be happy to communicate further off list.
- egs
On Fri, Jul 18, 2014 at 6:44 AM, Jeff Garzik <jgarzik@bitpay•com> wrote:
Quoted text (62 lines)
> Yes. That, and several other things. If you can figure out how to > propagate a block without re-propagating all the transactions everyone > already has, you address the large-blocks-slower-to-relay problem, and > additionally create an incentive for miners to mine blocks consisting > of publicly broadcast transactions (versus a bunch of secret ones > mined with secret agreements). > > Democratizing transaction selection takes a bit of power away from the > miners and gives it back to the network at large. GBT is another > piece of that puzzle. > > > On Fri, Jul 18, 2014 at 6:43 AM, Mike Hearn <mike@plan99•net> wrote: > > Oops, sorry, I see the subject line changed. This is what I get for > working > > down the thread list top to bottom :) > > > > I think the best path forward now is to finish off getblocktemplate > support > > in the various tools so it's possible to pool for payout purposes without > > giving up control of block creation modulo the coinbase. Combined with > the > > recent sipa performance enhancing goodness, it would hopefully persuade > some > > non-trivial chunk of hashpower to go back to running their own node and > > start the process of turning pools merely into payout trackers rather > than > > block selectors. > > > > > > On Fri, Jul 18, 2014 at 12:41 PM, Mike Hearn <mike@plan99•net> wrote: > >> > >> Jeff, I think the message you're replying to got clipped. > >> > >> Satoshi's only comment AFAIK on the topic of GPU mining was to wish for > a > >> gentlemen's agreement to postpone it as long as possible, to help make > sure > >> the distribution of coins was as even as possible. Indeed this predated > >> pooled mining. > >> > > > > > > -- > Jeff Garzik > Bitcoin core developer and open source evangelist > BitPay, Inc. https://bitpay.com/ > > > ------------------------------------------------------------------------------ > Want fast and easy access to all the code in your enterprise? Index and > search up to 200,000 lines of code with a free copy of Black Duck > Code Sight - the same software that powers the world's largest code > search on Ohloh, the Black Duck Open Hub! Try it now. > http://p.sf.net/sfu/bds > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists•sourceforge•net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development >
My apologies for posting to the wrong thread.
On Fri, Jul 18, 2014 at 5:51 PM, Emin Gün Sirer <el33th4x0r@gmail•com> wrote:
Quoted text (127 lines)
> I thought I'd chime in and point out some research results that might help. > Even if they don't, there is a cool underlying technique that some of you > might find interesting. > > The problem being tackled here is very similar to "set reconciliation," > where > peer A thinks that the set of transactions that should be in the block is > S_A, > and peer B has actually included set S_B, and S_A and S_B are expected > to not differ much. Ideally, one would like the communication complexity > between A and B to be O(delta), not O(S_B) as it is right now. And ideally, > one would like B to send a single message to A, and for A to figure out the > difference between the two sets, without any lengthy back and forth > communication. In essence, I would like to give you some magical packet > that is pretty small and communicates just the delta between what you and > I know. > > This paper from Cornell describes a scheme for achieving this: > Yaron Minsky, Ari Trachtenberg, Richard Zippel: Set reconciliation with > nearly optimal communication complexity. IEEE Transactions on Information > Theory 49(9): 2213-2218 (2003) > http://ipsit.bu.edu/documents/ieee-it3-web.pdf > > Those of you looking for a TL;DR should read the intro and then skip to > page 8 for the example. The underlying trick is very cool, comes from the > peer-to-peer/gossip literature, and it is underused. It'd be really cool > if it > could be applied to this problem to reduce the size of the packets. > > This approach has three benefits over the Bloom filter approach (if I > understand the Bloom filter idea correctly): > > (1) Bloom filters require packets that are still O(S_A), > > (2) Bloom filters are probabilistic, so require extra complications > when there is a hash collision. In the worst case, A might get confused > about which transaction B actually included, which would lead to a > fork. (I am not sure if I followed the Bloom filter idea fully -- this may > not happen with the proposal, but it's a possibility with a naive Bloom > filter implementation) > > (3) Bloom filters are interactive, so when A detects that B has included > some transactions that A does not know about, it has to send a message > to figure out what those transactions are. > > Set reconciliation is O(delta), non-probabilistic, and non-interactive. The > naive version requires that one have some idea of the size of the delta, > but I think the paper has some discussion of how to handle the delta > estimate. > > I have not gone through the full exercise of actually applying this trick > to > the Bitcoin p2p protocol yet, but wanted to draw your attention to it. > If someone is interested in applying this stuff to Bitcoin, I'd be happy > to communicate further off list. > > - egs > > > > On Fri, Jul 18, 2014 at 6:44 AM, Jeff Garzik <jgarzik@bitpay•com> wrote: > >> Yes. That, and several other things. If you can figure out how to >> propagate a block without re-propagating all the transactions everyone >> already has, you address the large-blocks-slower-to-relay problem, and >> additionally create an incentive for miners to mine blocks consisting >> of publicly broadcast transactions (versus a bunch of secret ones >> mined with secret agreements). >> >> Democratizing transaction selection takes a bit of power away from the >> miners and gives it back to the network at large. GBT is another >> piece of that puzzle. >> >> >> On Fri, Jul 18, 2014 at 6:43 AM, Mike Hearn <mike@plan99•net> wrote: >> > Oops, sorry, I see the subject line changed. This is what I get for >> working >> > down the thread list top to bottom :) >> > >> > I think the best path forward now is to finish off getblocktemplate >> support >> > in the various tools so it's possible to pool for payout purposes >> without >> > giving up control of block creation modulo the coinbase. Combined with >> the >> > recent sipa performance enhancing goodness, it would hopefully persuade >> some >> > non-trivial chunk of hashpower to go back to running their own node and >> > start the process of turning pools merely into payout trackers rather >> than >> > block selectors. >> > >> > >> > On Fri, Jul 18, 2014 at 12:41 PM, Mike Hearn <mike@plan99•net> wrote: >> >> >> >> Jeff, I think the message you're replying to got clipped. >> >> >> >> Satoshi's only comment AFAIK on the topic of GPU mining was to wish >> for a >> >> gentlemen's agreement to postpone it as long as possible, to help make >> sure >> >> the distribution of coins was as even as possible. Indeed this predated >> >> pooled mining. >> >> >> > >> >> >> >> -- >> Jeff Garzik >> Bitcoin core developer and open source evangelist >> BitPay, Inc. https://bitpay.com/ >> >> >> ------------------------------------------------------------------------------ >> Want fast and easy access to all the code in your enterprise? Index and >> search up to 200,000 lines of code with a free copy of Black Duck >> Code Sight - the same software that powers the world's largest code >> search on Ohloh, the Black Duck Open Hub! Try it now. >> http://p.sf.net/sfu/bds >> _______________________________________________ >> Bitcoin-development mailing list >> Bitcoin-development@lists•sourceforge•net >> https://lists.sourceforge.net/lists/listinfo/bitcoin-development >> > >