Intel NETMAP performance and packet type

[Slawa Olhovchenkov]

I am try use Intel 82599ES in NETMAP mode for filtering traffic.

For SYN-flood case my application can recive (by poll(2)) about
12-13Mpps by 2 thread at X5675 at 3.07GHz (all other traffic don't
recived by kernel).

For ACK-flood case  my application can recive (by poll(2)) only about
5.8Mpss by 2 thread at same hardware. I am talk only about receive
packets, don't processing.

What is wrong?
How to packet payload influence to NETMAP performance?

ix0: flags=28943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST,PPROMISC> metric 0 mtu 1500
        options=913838<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,WOL_UCAST,WOL_MCAST,WOL_MAGIC,VLAN_HWFILTER,NETMAP>
        ether 90:e2:ba:01:03:f6
        media: Ethernet autoselect (10Gbase-Twinax <full-duplex>)
        status: active
        nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
ix1: flags=28943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST,PPROMISC> metric 0 mtu 1500
        options=913838<VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,WOL_UCAST,WOL_MCAST,WOL_MAGIC,VLAN_HWFILTER,NETMAP>
        ether 90:e2:ba:01:03:f7
        media: Ethernet autoselect (10Gbase-Twinax <full-duplex>)
        status: active
        nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>