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Also, AFAICT `fsleep`'s busy wait is a >> bit nicer than just spinning. WDYT? I think switching this to Yes. >> Delta::from_micros(1) is probably better. > > Anything works for me as long as we reduce the spinning-induced latency > to something reasonable. I'll resping with `from_micros(1)`. That's good. thanks, -- John Hubbard