Cyclone V Dev Board Ethernet Driver Problem

Thanks in advance.

I'm using the GSRD 14.1 (Angstrom 3.10 ltsi) on my Cyclone V Dev Board.

We are attempting to use the 1Git ethernet to sustain 1,500,000 bytes/sec of changing data (pretty darn low bandwidth).

And we can't do it. I have enclosed a .pdf file with our test code, code output, and Wireshark graphs of the Ethernet traffic.

Here's the weird part --

if the data IS NOT changing (staticArray.c) then we keep up just fine.

If the data IS changing (changingArray.c) then the first ethernet packet goes out fine but after that it's horrible.

Any thoughts, ideas, known problems with the ethernet driver