When NXP created this chip, they characterized all peripherals.
What is the maximum sustained speed that the USB 3.0 actually achieved and which drivers were used?
response from NXP Technical Support Services that said it was a USB / xHCI performance issue. The best we can do with USB 3.0 right now is 150-170 MB/s on all iMX6 & iMX8 platforms. They proposed to request their Professional Services in order to optimize USB 3.0 throughput.