Every block re-ran z_listreceivedbyaddress for every z-address (O(wallet)
each, under cs_main) and a whole-wallet z_listsentbyaddress. On a 40-address
wallet that was ~80% of wall-clock. The history now advances in passes:
- an address is rescanned when it is stale by a number of blocks scaled to
its measured cost (8 to 500), never-scanned and hinted addresses first
(a hint: z_listunspent shows a note the history doesn't);
- z_listsentbyaddress covers only the blocks since the last good sweep
(+100 reorg margin); the whole-wallet sweep runs once per connect, with
a 10 min / 1 h / 6 h backoff after real failures;
- listtransactions pages are sized from last time, and an unchanged tip
reuses the transparent rows;
- found-but-unenriched txids carry over as a backlog; only -5 is a
definitive "not ours" for z_viewtransaction;
- between blocks, a cheap recent poll plus a one-address probe.
Duty model for a 40-address wallet at 10 s per scan: ~9% instead of ~80%.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
