Improve Ethernet throughput for jumbo frames - linux

Question

We are running throughput test on the gigE of Macnica Helio board with 1GB DDR3 specification.We are now achieving 60% (Jumbo frame) throughput, however we expect higher throughput in our application.
Method of calculation as following:-
(100M / time taken * 8-bit /1Gbps)*100%
What we did:
-Transfer 100MB using server and client code
Server(Cyclone V)
-change eth0 MTU 7500 (only achieve if we turn off tx checksum using ethtool "ethtool -K eth0 tx off" else we are just able to change the MTU up to 3500 only) then execute the server code
Client (Laptop runs UBUNTU)
-change eth0 MTU to 9000 then execute the client code and test the throughput performance using wireshark
We do try to change ipv4 setting using command below but throughput result is still the same
-sysctl -w net.core.rmem_max=18388608
-sysctl -w net.core.wmem_max=18388608
-sysctl -w net.core.rmem_default=1065536
-sysctl -w net.core.wmem_default=1065536
-sysctl -w net.ipv4.tcp_rmem=4096 87380 18388608
-sysctl -w net.ipv4.tcp_wmem=4096 87380 18388608
-sysctl -w net.ipv4.tcp_mem=18388608 18388608 18388608
-sysctl -w net.ipv4.route.flush=1
-sysctl -w net.ipv4.tcp_mtu_probing=1
Question
is there any method or solution to achieve higher throughput?
Is there any effect if we turn off the tx checksum?
What is the the different of tcp_congestion_control between cubic and bic and will it effect throughput performance?

Answer 1

Use ntop.org's PF_RING sockets instead of PF_INET sockets. We have been able to get up to 75% throughput with GigE Vision protocol (UDP) using Intel (e1000) NIC's, without using the NIC-specific PF_RING drivers.
AFAIK the tcp_congestion_control will only help you at the start of the TCP session and has no effect once the session is established.