b17 vs b19 on Hitachi 600 gb 15k RPM HDD: 54828 sec vs 54763 sec
on 10 tb Toshiba HDD: 52757 vs 58186 (b19 appears to be slower)
i'm comparing logs of plotter 1 out of 16 started simultaneously, better test would be with 1 plotter
and RAM (-b) was lower than recommended