Author: Anthony Towns 2020-01-14 03:20:26
Published on: 2020-01-14T03:20:26+00:00
A conversation on the bitcoin-dev mailing list discussed the ideal percentage of miners needed to upgrade to a new set of rules. The higher the percentage, the less likely there will be long chains of invalid blocks. However, having an 80% threshold may result in a 4% chance of non-enforcing miners producing both the next blocks, giving three confirmations to invalid transactions. Coinbase recently dropped its confirmation requirement to three, which isn't unrealistic. Some suggested a 90% threshold, but achieving 95% can prove challenging due to negligent miners forgetting to upgrade. However, during the BIP-91/148 period, they went from 59% to 54% to 28% to 0% of blocks not signaling for segwit, and from 100% of blocks not signaling for BIP-91 to 99.4%, 48%, 15%, and 11% during consecutive periods targeting an 80% threshold. For CSV, they went from 100% not signaling to 61%, to 54% to 3.4% in consecutive two-week periods. Matt's goal #5 aims to prevent a small malicious minority from delaying activation. While the fallback to BIP-8 helps, BIP-9’s 95% requirement allows a neglected minority to force a dramatic delay. Skipping BIP-9 altogether would be better in such cases. However, skipping steps is not possible when you need a flag day. The first 12 months are for ensuring no problems arise with the proposed upgrade, followed by six months to lock in the flag day, and another 24 months to ensure everyone upgrades their nodes to avoid Bitcoin thinking they've received coins that aren't compliant with the new rules. It is essential to have hash power reliably enforcing the rules, which requires everyone to upgrade their nodes, leading to a long overall lead time. The overall timeline of 42 months seems plausible, with around 0.5% of nodes running 0.12 or earlier and around 4.9% of nodes running 0.13 or earlier. The conversation also discussed the failure case if miners false-signal support of new soft-fork rules but do not enforce them.
Updated on: 2023-05-20T21:29:33.021941+00:00