Comment 33 for bug 1519897

Based on the numbers here, I will continue to include some patches or suggestions we got from Haiyang, and send an update later.
You should be able to push the update as this seems to be a problem with 3.13 entire tree, then in a separate thread we can identify the missing patches.

These are the numbers that we have when running a simple test with ntttcp.
All the below 3 kernels have been installed from the trusty-proposed repo.

As a reference, on the same system but with the latest available kernel we have this:
Kernel: lts-vivid - 3.19.0.50 (56)
Throughput: 12.87Gbps

Our historical perf testing includes only kernel 3.16.0-59 for 14.04, for which we got a throughput of 18.02 Gbps.

Distribution release: Ubuntu 14.04.3

Kernel: 3.13.0-76-generic (120)
Throughput: 1.53Gbps

Kernel: 3.13.0-77-generic (121)
Throughput: 1.41Gbps

Kernel: 3.13.0-78-generic (122)
Throughput: 1.50Gbps

Going back to try and find a good build, picking up the first 3.13 kernel:
Kernel: 3.13.0-24-generic (122)
Throughput: 1.50Gbps