What is it, and why use it?
As of this writing, the space necessary for a BTG Full Node (by running the BTG Core Wallet) is approaching 170 GB. If you want to run a Full Node, but have limited drive space, you can still run a full node in Pruned Mode. This will allow your node to discard older blocks after using them for validation.
A Pruned Node will participate fully in the live network, relaying new blocks and relaying new transactions, confirming them, adding them to your chainstate database, just like an unpruned node. The only thing a Pruned Node cannot do is hand out old blocks to new nodes that ask for them.
Turning on Pruned Mode
You set pruned mode in your .conf file like this:
Or add it on as a command line switch like this:
This setting will prune your block storage down to 2000 Megs (2GB of the latest blocks) by deleting older blocks. You can set any number you like, as long as it’s 550 or greater.
In the new v0.17.1 version (coming soon) you can set it in the Options/Main menu:
Your Pruned Full Node will now consume roughly 5GB of space. It will keep a full Chainstate database, which consumes less than 3GB at this time, and it will keep 2 GB of the latest blocks,
If you turn on pruned mode and old blocks are deleted, you cannot easily “reindex” your node. Reindexing means going back to the beginning and adding things up again… and your node has thrown out the old blocks. To reindex on a pruned node, you’ll have to re-sync the entire chain from the beginning again, which takes as long as your first sync did. For most of us, this won’t matter.
Also, we do need Full Nodes on the network to handout the old blocks for the new nodes. If you have the space to keep all the old blocks around, go ahead and keep them around!
If you start your node in Pruned mode from scratch on an empty drive, it will still need to download all blocks, from the very first block, to validate them (and their transactions) in order. The node will begin throwing away the oldest ones as your size limit gets exceeded.
If you turn on Pruned mode while you already have all the blocks on disk, pruned mode will immediately throw out old blocks to free up space. You can’t easily get these “back”, they are deleted. You can’t turn this on and then change your mind and turn it off - those old blocks don’t come back, and if you need them, your node will need to download them again.