What does limiting block storage to 2GB on a pruned node actually mean?

So, if I limit my block storage to 2GB, does that mean my node only keeps the latest 2GB of blockchain data? What if I set it to 50GB instead? What’s the benefit of more space?

Yep, that’s right. It’ll maintain your blockchain under that size limit. The bigger the limit, the more blocks it retains. This can be key when you need to rescan older blocks, especially if you’re loading a wallet that has transactions from further back. Once the blocks are pruned, you can’t rescan those.

Just so you know, other data like UTXO is not pruned and takes up about 11.8GB. You need more than 2GB free to run Bitcoin Core. No real perk for casual use, but if you need to access older info, it’s good to have some extra space to avoid re-downloading everything.

From what I recall, a pruned node will keep all relevant blocks for wallets that have transactions, even if those blocks are beyond the prune limit. If your wallet has a lot of transaction history, it might be smart to set a higher limit, like 10 or 20GB, just to be safe.

Are you sure about this? Seems kinda pointless to me. A wallet just needs the raw transaction data and maybe the block height or hash, not all that extra stuff.

Not super confident in what I said. My memory’s a bit fuzzy on this pruning stuff. But yeah, wallets in Bitcoin Core do keep their transaction lists, which aren't affected by pruning, as Pieter Wuille mentioned once.

I see where you’re coming from, but maintaining blocks for wallets with tons of transactions could eat up significant space, like several GB. Not sure that actually happens, though.