Ok, got full validation running with my single peer blocks first sequential sync. So no concurrency whatsoever (and no checkpoints). Time flattened out pretty quickly with respect to tx count and total archive byte count. And everything else we've seen has maintained at least constant time for the full chain. Using a linear projection based on the tx rate and byte rate the total time to block 780,000 will be 3.25 days. This includes adding in the known 1.5hs for sequential metadata writes. CPU flat at 2%.
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