rich1.0npub17rld56k4365lfphyd8u8kwuejey5xcazdxptserx03wc4jc9g24stx9l2hhttps://nostr.ae/npub17rld56k4365lfphyd8u8kwuejey5xcazdxptserx03wc4jc9g24stx9l2hnjumphttps://nostr.ae📅 Original date posted:2015-08-02 📝 Original message:On Thu, Jul 30, 2015 at 12:20:30PM -0400, Gavin Andresen wrote: > On Thu, Jul 30, 2015 at 10:25 AM, Pieter Wuille via bitcoin-dev > > Some things are not included yet, such as a testnet whose size runs ahead > > of the main chain, and the inclusion of Gavin's more accurate sigop > > checking after the hard fork. > First, THANK YOU for making a concrete proposal! > So we'd get to 2MB blocks in the year 2021. I think that is much too > conservative, and the most likely effect of being that conservative is that > the main blockchain becomes a settlement network, affordable only for > large-value transactions. I haven't seen anyone do the (trivial) maths on this. Have I just missed it? By my count: - blocks in 25 btc in rewards and about 0.5 btc in fees per block - at ~$300 USD per btc, that's ~$7,650 per block - current hashrate is ~400 PH/s; so ~240,000 PH/block works out to having to spend about 30PH per dollar earnt. - for comparison, https://products.butterflylabs.com/cloud-mining-contracts.html quotes $1.99 per GH/s for 12 months, which by my count is 60*60*24*365 / 1.99 GH/$ = 15.8 PH per dollar spent - hashrate growth has slowed from about x4/quarter to x2/year: sep '13: ~1PH/s dec '13: ~4PH/s mar '14: ~20PH/s jun '14: ~80PH/s sep '14: ~200PH/s aug '15: ~400PH/s - so, as far as I understand it, miners don't make absurd profits compared to capital investment and running costs - presumably, then, miners will stop mining bitcoin if the revenue/block drops significantly at some point - less miners means a lower hashrate; a lower hashrate makes 50% attacks easier, and that's a bad thing (especially if there's lots of pre-loved ASIC mining hardware available cheap on ebay or alibaba) - in about a year, the block reward halves, cutting out 12.5 btc or ~$3750 USD per block. without an increase in fees per block, miners will just get ~$3900 USD per block - the last time the reward for mining a block was under $4000 per block was around oct '13, with a hashrate of ~2PH/s - 13 btc in fees per block compared to .5 btc in fees per block is a 25x increase; which could be either an increase in fee/txn or txns/block - with ~500 bytes/transaction, that's ~2000 transactions per MB - 13 btc in fees ($3900) per block means per transaction fees of about $2 for 1MB blocks $1 for 2MB blocks 25c for 8MB blocks 10c for 20MB blocks (assuming full blocks, 500 byte txns) - comparing that to credit card or paypal fees at ~2.5% that's: $2 -> minimum transaction $80 $1 -> minimum transaction $40 25c -> minimum transaction $10 10c -> minimum transaction $4 - those numbers only depend on the USD/BTC exchange rate in so far as the more USD for a BTC, the more likely the block reward will pay for hashrate without transaction fees, even with the reward reduced to 12.5 btc/block. otherwise it's just USD/txn paying for USD/hashrate - the reference implementation fee of 0.1mBTC/kB equates to about 3c per transaction (since it rounds up). Even 10c/transaction is more than a 3x increase on that. What the above says to me is that even assuming everyone starts paying fees, the lightning network works great, and so do sidechains and whatever else, you /still/ want to up the volume of bitcoin txns by something like an order of magnitude above what's currently allowed within a year or so. Cheers, aj