Why doesn't igb driver set the wthresh it wants as default?
I see:
PMD: eth_igb_tx_queue_setup(): To improve 1G driver performance,
consider setting the TX WTHRESH value to 4, 8, or 16.
But the default tx_conf has wthresh of 0.
#define IGB_DEFAULT_TX_WTHRESH 0
Either message should be removed or default TX wthresh should change.

