The CDBCAM default settings are configured for the Fast Lookup mode, which provides more than double the lookup rate at the cost of some additional FPGA resources (typically 1.5k LUTs, depending on the key size). In this mode, the lookup performance is almost three times greater than in a non-fast mode, when the table is up to 30% full, but drops to just over two times greater performance when table is 80%+ full. If you do not want to avail of this performance gain, use the following Tcl command before generating the IP.
set_property CONFIG.FAST_LOOKUP false [get_bd_cells cdcam_0]