On Mon, Jan 31, 2022 at 04:57:52PM +0100, Bastien TEINTURIER via bitcoin-dev wrote: > I'd like to propose a different way of looking at descendants that makes > it easier to design the new rules. The way I understand it, limiting the > impact on descendant transactions is only important for DoS protection, > not for incentive compatibility. I would argue that after evictions, > descendant transactions will be submitted again (because they represent > transactions that people actually want to make),
I think that's backwards: we're trying to discourage people from wasting the network's bandwidth, which they would do by publishing transactions that will never get confirmed -- if they were to eventually get confirmed it wouldn't be a waste of bandwith, after all. But if the original descendent txs were that sort of spam, then they may well not be submitted again if the ancestor tx reaches a fee rate that's actually likely to confirm. I wonder sometimes if it could be sufficient to just have a relay rate limit and prioritise by ancestor feerate though. Maybe something like: - instead of adding txs to each peers setInventoryTxToSend immediately, set a mempool flag "relayed=false" - on a time delay, add the top N (by fee rate) "relayed=false" txs to each peer's setInventoryTxToSend and mark them as "relayed=true"; calculate how much kB those txs were, and do this again after SIZE/RATELIMIT seconds - don't include "relayed=false" txs when building blocks? - keep high-feerate evicted txs around for a while in case they get mined by someone else to improve compact block relay, a la the orphan pool? That way if the network is busy, any attempt to do low fee rate tx spam will just cause those txs to sit as relayed=false until they're replaced or the network becomes less busy and they're worth relaying. And your actual mempool accept policy can just be "is this tx a higher fee rate than the txs it replaces"... > Even if bitcoin core releases a new version with updated RBF rules, as a > wallet you'll need to keep using the old rules for a long time if you > want to be safe. All you need is for there to be *a* path that follows the new relay rules and gets from your node/wallet to perhaps 10% of hashpower, which seems like something wallet providers could construct relatively quickly? Cheers, aj _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
