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How Monero’s proof of work works

blog.alcazarsec.com

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Re: How Monero’s proof of work works

#201

Post by donaldjbiden »

AureliusMA wrote: post #44
latchkey wrote: post #35

Earlier quoted context omitted.

It is subtle, but PoW mining itself doesn't generate coins. It isn't like someone is digging a hole in the ground and extracting gold. PoW miners are rewarded for correctly validating transactions, with newly minted coins. The whole proof of work thing is that you proved that you validated a transaction by expending energy, and the network pays you for that security service. Miners then need to sell those coins on th…

Agreed with your explanation. I would add a different way to make sense of it. Proof of work allows for what Keynes called "Bancor". BTC is succesful because unlike fiat central banks, the money supply isn't dictated by interest rates (and thus loans) but by the effort of participants. The price of BTC is almost irrelevant, BTC itself is a paradigm shift. Regarding the fixed supply, it's only fixed because participan…

The money supply of BTC has a fixed schedule. It has nothing to do with the effort of participants.

Re: How Monero’s proof of work works

#202

Post by Terr_ »

dragonwriter wrote: post #72
j4cobgarby wrote: post #5

I never quite understand this stuff, maybe someone can help. Are cryptocurrencies supposed to be a potential replacement for real life cash? This was my understanding of the motivation behind Bitcoin, at least. If so, why does it make sense that people can "generate" cash by proving some amount of work done? This of course cannot be done with normal cash. Is the main functionality of these cryptocurrencies supposed t…

> Are cryptocurrencies supposed to be a potential replacement for real life cash? They are supposed to be a medium of exchange. “Real life cash” is one of many forms of money; even for any particularly currency, like dollars, a very small fraction of use is “real life cash”. But, yes, in the most extreme visions, cryptocurrencies replace other currencies for all uses. More moderate visions, however, exist. So, as alw…

> More moderate visions, however, exist. So, as always when you use “supposed”, the answer is undefined without qualifying it as to by whom it is supposed.

And in some cases, which mutually-inconsistent argument the same entities are making. For example, when the thing's a dollar-replacing currency at the start of the interview, and can't-miss investment commodity by the end of it.

Re: How Monero’s proof of work works

#203

Post by tardedmeme »

kyleee wrote: post #198
tardedmeme wrote: post #112

Earlier quoted context omitted.

I'm not sure that I'd cite being able to donate to terrorists as a legitimate use case. I mean, at the protocol level, donating to a terrorist is the same as donating to anyone else, so a system that lets you donate to anyone will necessarily let you donate to terrorists, but it wouldn't be the example I'd bring up in polite conversation.

Remember that nelson Mandela was considered a terrorist too

So was Osama bin Laden.

Re: How Monero’s proof of work works

#204

Post by hyc_symas »

tardedmeme wrote: post #105
OsrsNeedsf2P wrote: post #82

Earlier quoted context omitted.

Right, but the program is generated by the miner. So the miner could just generate a program that has no branching, and run it on a GPU.

Each program is guaranteed to have a certain number of certain types of instructions, such as (IIRC) exactly one divide instruction.

Since the programs are randomly generated, there's no guarantee that any particular program always uses some number of any particular instruction. There's only a probability, X/256 instructions will be somesuch operation.

Re: How Monero’s proof of work works

#205

Post by hyc_symas »

Nevermark wrote: post #192
rschneid wrote: post #161

Earlier quoted context omitted.

It's a proof that something is possible to show one example. In this case the claim was ASIC-resistant PoW is possible, and the proof has been the historical behavior of miners after years of RandomX. Nobody said it would be eternally or entirely resistant to optimizations...

You are twisting words beyon any coherent meaning. > It's a proof that something is possible to show one example. Agreed. > the proof has been the historical behavior of miners after years of RandomX. > Nobody said it would be eternally or entirely resistant to optimizations... These are contradictory statements. If historical behavior was a proof, then it would be eternally and entirely resistant.

The limit we set at the beginning was "no one can design a custom device for RandomX with more than a 2:1 efficiency advantage over general purpose CPUs". That is and will forever remain true.

In reality, no one has been able to build any device for RandomX that isn't actually a CPU. The closest thing to a "mining ASIC" is just a bunch of RISC-V cores.

Re: How Monero’s proof of work works

#206

Post by snthpy »

As PoW goes, this is cool.

One thing I didn't understand though is Light mode:

> Fast mode is for mining. Light mode is for verification. The reference README says

The post only describes Fast mode, right?

Presumably verification is done by miners who already have the memory set up so Fast mode would be faster for them.

Verification is still relatively fast because you don't have to try gazillions of nonces so who is Light mode necessary and how does it work?

Re: How Monero’s proof of work works

#207

Post by hyc_symas »

snthpy wrote: post #206

As PoW goes, this is cool. One thing I didn't understand though is Light mode: > Fast mode is for mining. Light mode is for verification. The reference README says The post only describes Fast mode, right? Presumably verification is done by miners who already have the memory set up so Fast mode would be faster for them. Verification is still relatively fast because you don't have to try gazillions of nonces so who is…

Light mode is used mostly by the monerod, validating incoming blocks. But on a machine with sufficient free RAM, monerod can also be set to use Fast mode instead.

The post described both modes. The only difference is that Fast mode processes the cache to generate the full 2.1GB dataset, so subsequent programs can just reference it as needed. Light mode uses only the 256MB cache and generates the required dataset values individually, on each access. That saves RAM but costs more CPU time.

Re: How Monero’s proof of work works

#208

Post by hyc_symas »

ProllyInfamous wrote: post #144
hyc_symas wrote: post #120

Earlier quoted context omitted.

> Once you kill the process, your local blockchain is [most likely] unusable. Totally false. LMDB is perfectly crash-proof in that scenario and killing the process never damages the DB. The only thing that's not guaranteed is turning off syncs, in the face of an OS crash/power outage. If you don't sync, you're not abusing the SSD. If you run on Windows, the OS is too unstable to use without safe sync mode though.

>Totally false. This is a well-documented failstate. Usually results in "unable to connect to 127.0.0.1:18081" errorlog, which is most-commonly due to a corrupt database/blockchain (from hardstop/kill). In order of crashout likelihood: Windows >> MacOS > Linux >If you don't sync, you're not abusing the SSD. If you don't sync then you're not (cannot be) a fullnode / network verifyer / ringsigner. ---- >LMDB is perfect…

> If you don't sync then you're not (cannot be) a fullnode / network verifyer / ringsigner.

I was talking about database sync, not blockchain sync. You don't need to use safe sync mode if you don't have to worry about machine crashes. And just killing the process will never corrupt the blockchain DB.

> This may be old behavior... I go way back

On this particular point, I go way back further than you.

Re: How Monero’s proof of work works

#210

Post by hggh »

tardedmeme wrote: post #99
ulrikrasmussen wrote: post #17

Earlier quoted context omitted.

It's just a mechanism to incentivize mining. The alternative is that miners are paid only via fees, but that risks making it prohibitively expensive to transact. Minting new coins distributes the cost of mining over all holders by inflating the currency a little bit. Fees are still necessary to avoid spamming.

Bitcoin was intended to be funded entirely by transaction fees and the minting was just to jumpstart the currency, which is why the new coin minting rate tends to zero. This was a naïve mistake. Other cryptocurrencies have start high and approach a lower nonzero value.

> Bitcoin was intended to be funded entirely by transaction fees

Transaction fees used to be free, but miners started to require at least 1 sat/b, to prevent "spamming" the mempool, so... no.

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