This worked out nicely, tested and merged. I've added a bn command line option that disables console out. This dramatically reduces shutdown latency with high volume logging. I'm now testing at 5,000 connections, batched 5 at a time (25,000 connection attempts). These levels of connectivity used to crash my router. The new one has had no problems. CPU is almost nothing (~.15%), memory is a modest linear scale, and I/O is also small. I've got 32 of my 64 cores configured on network, but it's never using more than 10. Still not a single crash or deadlock and shutdown is almost instantaneous regardless of the connection count.
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