@JasonHrubizna1 If you set the Parallel Processing Factor to a number of processes greater than or equal to the number of system cores on your machine, then it will result in worse performance. Under those circumstances, your are forcing the swapping of a greater number of process across a lesser number of cores, so the overhead slows things done. Hence, when you choose 100% (and greater), you were slowing things down with that overhead (assuming other factors, such as I/O or memory, were not bottlenecks.)
To achieve the maximum performance boost from parallel processing, you should choose a number (or percentage) that results in at least one core being left available for running processes other than the tiling job. Depending on what else you are doing on the computer while the tile job is running, you may even need to leave additional cores available to get maximum performance out of the cores being used for the tiling job.
