What's the fastest way to sync a node only keeping full state for the last N blocks?

Question

I need to only keep state for the last few blocks, but I don't want to wait for the full sync of the node, is there a way to do that faster than by using --sync=full? Because it seems like all the current modes either download the full history or just the latest state.

Answer 1

Check this guide from the Polkadot Wiki: Set up a Full Node. Running as a simple sync node, only the state of the past 256 blocks will be kept, if you want all the history run as an Archive Node.

If you want a faster sync you can use the flag --sync warp

--sync <SYNC_MODE>
    Blockchain syncing mode.
    
    - `full`: Download and validate full blockchain history.
    - `fast`: Download blocks and the latest state only.
    - `fast-unsafe`: Same as `fast`, but skip downloading state proofs.
    - `warp`: Download the latest state and proof.

More information about why is faster: Is GRANDPA warp sync the recommended method for syncing a node? and in the Polkadot Protocol Specification.