Ticket 49021 - Automatic thread tuning
Bug Description: We currently always set 30 threads on systems no matter their
size. We should tune the threads more appropriately out of the box.
Fix Description: Add a thread autotuning. We start at 16 threads, and ramp up,
reducing the rate off addition as we grow to a cap of 512 threads.
https://fedorahosted.org/389/ticket/49021
Author: wibrown
Review by: nhosoi, mreynolds (Thanks)