What to do with well working polling and how to determine it

[strizhechenko]

case:

 27:   48654883   48544883   PCI-MSI-edge      eth0
 28: 3101331408 3101444157   PCI-MSI-edge      eth1
 30:   95332395   95334018   PCI-MSI-edge      eth2

and second case:

 28: 3101331408  0   3101444157   0   PCI-MSI-edge      eth1

maybe it will be better to skip rss part.

[strizhechenko]

We must look at the difference between rates. Less than 30% means that everything works fine.

[strizhechenko]

@nick-carbonsoft thinks it's good idea to use irqtop too.