How to make bitcoin-qt respect -prune?

I'm using Bitcoin Core 0.18.0-rc2 (64-bit) on Qt 5.9.7.

How can I make it respect -prune=550?

This is the minimum prune number, and should be approximately 550 MB.

Yet, my client is downloading tens of gigabytes worth of data, with no end in sight.

In "Options" it is stated:

"Options set in this dialog are overridden by the command line or in the configuration file: -prune=550"

Hence, it seems like the program is able to recognize the command line argument. It simply doesn't respect it as far as downloading and pruning the blockchain goes.

What can I do differently to fix this problem?

AlphaCentauri

Posted 2019-03-24T15:15:29.143

Reputation: 119

Answers

prune allows you to set the size of blockchain data stored, not downloaded. Therefore prune does not affect bandwidth usage.

MCCCS

Posted 2019-03-24T15:15:29.143

Reputation: 5 827

TL;DR: A pruned node is a fully validating node that is not an archival node. It does still process the whole blockchain from scratch, though.

Bitcoin Core is a fully validating node. Fully validating nodes check the entire blockchain from scratch to converge on the latest state of the network independently. By default Bitcoin Core runs as an archival node, where it keeps all blocks to serve them to other participants of the network. Running a Bitcoin node with -prune limits the data footprint of the node by discarding old block data after it has been verified. The pruned node keeps the newest blocks up to the specified data limit. Running a full node in pruning mode does not reduce the inbound bandwidth. Since it can only serve the latest blocks, it does reduce the outbound bandwidth indirectly.

To limit your bandwidth consumption, you can run in -blocksonly mode and disable peer services. If you don't want to download the full blockchain at home, you could download it somewhere else with a mobile device or copy it from another node (then preferably reindex to independently verify its validity). If neither is an option, you could look into other wallets that are not a fully validating node.

Murch

Posted 2019-03-24T15:15:29.143

Reputation: 41 609

Are you saying there are clients that would allow me to use my wallet locally, without downloading the entire blockchain? I'm not that comfortable with the terminology. If so, what clients should I use? – AlphaCentauri – 2019-03-25T00:18:26.830

Check out https://btcinformation.org/en/choose-your-wallet. You may want to have a look at Electrum for example.

– Murch – 2019-03-26T17:56:21.910