Lately I’ve been fucking around and been finding out.

I had an unconfirmed #bitcoin transaction from more than a month ago that was sent to me from a non-kyc exchange. I had set the fee way too low based on nostr:npub1cyh2mhmvjgplma5de0muydkt0uk6hlynpn7gas4r6xc6zu9utufsststls (my mistake, I trusted, but did not verify - I rectified this by building nostr:npub17q7l84qnggcyyrxl0t9mxhuk5f2zgfpyd2c99w3ycmlvdfx57emqazk5dk and nostr:npub1u7lcmtfkpq50q2ym0d975xsm628td4xk2gh6zlu40cxlhqu770dslk7jgm myself).

I decided to see whether the fees would come down. After a couple of weeks I told myself I would fix the situation with a CPFP transaction. Thinking I would do this when the fees would come down at least a little bit, the node of the exchange eventually dropped my unconfirmed transaction…

The only node - that I could find - that was still showing my transaction was mempool.space. nostr:npub18d4r6wanxkyrdfjdrjqzj2ukua5cas669ew2g5w7lf4a8te7awzqey6lt3 offers an acceleration service since a while. It’s not cheap, but it was my best bet, until I figured out I could contact the exchange to RBF the transaction.

The support team was amazing and RBF’ed my transaction. The fees were a bit higher then I was hoping for, since the fee environment was relatively high when they came around to RBF my transaction, but at least my transactions is finally confirmed after many weeks!

Lessons learned about the #mempool that I never knew before

✅ Nodes store unconfirmed transactions for 14 days by default (correct me if I’m wrong) or until they are purged based on fees

✅ Nodes can change the default storage period (shorter or longer)

✅ Nodes can refuse to purge unconfirmed transaction - mempool.space does this, that’s why their memory is much higher than the limit 1.63 GB / 300 MB and why it was the only node that still had my unconfirmed transaction