The interesting display to look at when you get "no buffer space 
available" is the output from:

	netstat -m

However, I will bet a whole lot that it will show no requests for 
buffers refused. This is because there is another, distinct error 
condition which returns that error code: network interface queue full.

When a network interface cannot transmit, for whatever reason, the 
kernel will limit the number of packets that can be queued for 
transmit on that interface. However, when that queue fills up, the 
error returned is ENOBUFS.

There is an open PR suggesting that a new error code be allocated for 
this case.

	Erik <fair@clock.org>