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New RPCs- The scanblocks RPC returns the relevant blockhashes from a set of descriptors by
scanning all blockfilters in the given range. It can be used in combination with
the getblockheader and rescanblockchain RPCs to achieve fast wallet rescans. Note
that this functionality can only be used if a compact block filter index
(-blockfilterindex=1) has been constructed by the node. (#23549)
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Wallet...
- Rescans for descriptor wallets are now significantly faster if compact
block filters (BIP158) are available. Since those are not constructed
by default, the configuration option "-blockfilterindex=1" has to be
provided to take advantage of the optimization. This improves the
performance of the RPC calls rescanblockchain, importdescriptors
and restorewallet. (#25957)
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I have assembled a watch-only wallet of more than 21000 combo(PubKey) descriptors and before v25.0 it took literally ages to rescan over the whole blockchain. Now with v25.0 I saw a significant speed-up. I wish I had this version quite some months ago. I ran a part of this wallet's rescan on a low energy consuming Raspberry Pi which isn't known for its computing power, so I was aware that it can take a while. But I didn't anticipate that with prior versions of Core it would take months for the rescan!