Running 400-450k now, with a 10k download step. That caused all downloads to complete in 10.5 minutes (blocks orders of magnitude larger in this range from prior) while validation was accelerated as expected, with 29k out of 50k blocks completing in that 10.5 minutes. So almost 60% complete now vs. 35% in the previous run with the 50k vs. 10k step. Still 100% CPU from the point where the first step completed.
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