On Sun, Feb 07, 2016 at 09:16:02AM -0500, Gavin Andresen via bitcoin-dev wrote: > There will be approximately zero percentage of hash power left on the > weaker branch of the fork, based on past soft-fork adoption by miners (they > upgrade VERY quickly from 75% to over 95%).
The stated reasoning for 75% versus 95% is "because it gives "veto power" to a single big solo miner or mining pool". But if a 20% miner wants to "veto" the upgrade, with a 75% threshold, they could instead simply use their hashpower to vote for an upgrade, but then not mine anything on the new chain. At that point there'd be as little as 55% mining the new 2MB chain with 45% of hashpower remaining on the old chain. That'd be 18 minute blocks versus 22 minute blocks, which doesn't seem like much of a difference in practice, and at that point hashpower could plausibly end up switching almost entirely back to the original consensus rules prior to the grace period ending. With a non-consensus fork, I think you need to expect people involved to potentially act in ways that aren't very gentlemanly, and guard against it if you want the fork to be anything other than a huge mess. Cheers, aj _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
