Speedup interchange.DeviceResourcesExample

[eddieh-xlnx]

$ java -Xmx16G com.xilinx.rapidwright.interchange.DeviceResourcesExample xcvu3p-ffvc1517-2-e
==============================================================================
==                Device Resources Dump: xcvu3p-ffvc1517-2-e                ==
==============================================================================
             Load Device:     1.536s    311.495MBs          |    686.973MBs (peak)
           populateEnums:     0.266s     31.893MBs          |    686.973MBs (peak)
               SiteTypes:     0.142s     14.099MBs          |    686.973MBs (peak)
               TileTypes:     0.211s      0.257MBs          |    686.973MBs (peak)
                   Tiles:     0.155s     32.004MBs          |    686.973MBs (peak)
             Wires&Nodes:   231.024s   2903.914MBs          |  15902.168MBs (peak)
            Prims&Macros:     0.598s     52.715MBs          |  15902.168MBs (peak)
    Cell <-> BEL pin map:   111.007s      7.453MBs          |  17559.805MBs (peak)
                Packages:     0.019s      0.066MBs          |  17559.805MBs (peak)
               Constants:     9.335s      4.997MBs          |  17559.805MBs (peak)
              Wire Types:     0.007s      0.008MBs          |  17559.805MBs (peak)
                 Strings:     0.067s      0.001MBs          |  17559.805MBs (peak)
              Write File:   164.255s     -0.031MBs          |  17559.805MBs (peak)
             Verify file:   116.958s    693.583MBs          |  17559.805MBs (peak)
------------------------------------------------------------------------------
                 *Total*:   635.579s   4052.456MBs          |  17559.805MBs (peak)

to generate a ~350MB file.