ixgbe input errors at high data rates

[rihad]

rihad wrote:
> Turning LRO off (ifconfig x.x.x.x -lro) instantly stopped the 
> "Fragmentation failed" errors and solved the problem. Thank you.
> 

Alas, although turning LRO off, and raising dev.ix.0.rx_processing_limit 
from 100 to 2048 helped much, tweaking isn't over just yet. According to 
www.speedtest.net the ADSL speed's fine early in the morning, but as 
more users come online and more traffic goes through the FreeBSD box the 
speed gradually falls to 1/2 or 1/3 of the expected value, even when 
picking a target server in your own city. File downloads are roughly 
1/2-1/3 slower.