What issues would changing the default mempool policy in Core to mempoolfullrbf=1 resolve and which of the current policy proposals (e.g. BIP125 replacement, V3 Policy, package RBF, discussed here) would be simplified?

  • 1
    Your question is quite broad and covers multiple topics, which makes it difficult to answer. I'd suggest giving bitcoin.stackexchange.com/help/how-to-ask a read and breaking this down into more specific questions. Ideally, your post should mention what research you've done already and ask as specific of a question as possible.
    – josie
    Feb 23, 2023 at 9:44
  • @josie: This is a specific question even if it is difficult to answer. I link to an alternative question on the status of these proposals. If you can't answer the question that's fine (I am also struggling to) but I don't think I need a tutorial on how to ask questions on this site to try to understand this, thanks. Mar 1, 2023 at 11:39

1 Answer 1


This is a work in progress answer. As always alternative answers are welcome.

The -mempoolfullrbf option when set to 1 ignores RBF signaling and assumes every transaction can be RBFed. This option was introduced in Bitcoin Core v24.0 although it was off by default in 24.0. For more discussion on the introduction of the mempoolfullrbf option see this question.

If the default mempool policy in Core was set to mempoolfullrbf=1 then one would assume that within 1-2 years the majority of Core nodes (and the majority of nodes on the network) would be running this policy (when they update to a new version). Of course users have the option to change from the default but in reality most seem to run with policy defaults.

The V3 Policy proposal introduces an additional set of rules to existing standardness and policy rules (V2 Policy?). This includes RBF signaling so it seems to be proceeding assuming that transactions do still need to signal that they are replaceable and we are not assuming a network of nodes running the mempoolfullrbf=1 option. Even if the majority of the network was running that option one would assume there would be a minority of the network checking RBF signaling rules were being applied correctly.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.