Just some more infos: it seems to me that dropped packets are more
numerous than with old kernel (3.2.0)...
# while [ true ]; do ifconfig eth7 | grep "RX pa" ; sleep 1; done
RX packets:996942121 errors:0 dropped:303351 overruns:0
frame:0
RX packets:997020717 errors:0 dropped:303371 overruns:0
frame:0
RX packets:997084730 errors:0 dropped:303384 overruns:0
frame:0
RX packets:997154572 errors:0 dropped:303404 overruns:0
frame:0
RX packets:997220453 errors:0 dropped:303425 overruns:0
frame:0
RX packets:997285777 errors:0 dropped:303453 overruns:0
frame:0
RX packets:997359794 errors:0 dropped:303534 overruns:0
frame:0
RX packets:997425042 errors:0 dropped:303558 overruns:0
frame:0
RX packets:997494121 errors:0 dropped:303591 overruns:0
frame:0
RX packets:997566302 errors:0 dropped:303607 overruns:0
frame:0
RX packets:997633935 errors:0 dropped:303640 overruns:0
frame:0
dmesg when run the script:
[20712.690518] Intel(R) 10 Gigabit PCI Express Network Driver -
version 3.18.7
[20712.690522] Copyright (c) 1999-2013 Intel Corporation.
[20712.690939] ixgbe: Interrupt Throttling Rate (ints/sec) set to 4000
[20712.690946] ixgbe: Flow Director packet buffer allocation set to 3
... (cut port 0)
[20712.855655] ixgbe: 0000:04:00.1: ixgbe_check_options: FCoE Offload
feature enabled
[20713.016347] ixgbe 0000:04:00.1: irq 133 for MSI/MSI-X
(other 15 lines for IRQ mapping)
[20713.018469] ixgbe 0000:04:00.1: (PCI Express:5.0GT/s:Width x8)
38:ea:a7:92:e5:b0
[20713.018789] ixgbe 0000:04:00.1 eth7: MAC: 2, PHY: 12, SFP+: 5, PBA
No: G43260-006
[20713.018791] ixgbe 0000:04:00.1: PCI Express bandwidth of 32GT/s
available
[20713.018792] ixgbe 0000:04:00.1: (Speed:5.0GT/s, Width: x8, Encoding
Loss:20%)
[20713.018795] ixgbe 0000:04:00.1 eth7: Enabled Features: RxQ: 16 TxQ:
16 FdirHash RSC
[20713.018836] ixgbe 0000:04:00.1 eth7: Intel(R) 10 Gigabit Network
Connection
[20713.199922] IPv6: ADDRCONF(NETDEV_UP): eth7: link is not ready
[20713.282466] ixgbe 0000:04:00.1: irq 133 for MSI/MSI-X
(other 15 lines for IRQ mapping)
[20713.664787] ixgbe 0000:04:00.1 eth7: enabling UDP RSS: fragmented
packets may arrive out of order to the stack above
[20714.271637] ixgbe 0000:04:00.1 eth7: detected SFP+: 5
[20714.919611] ixgbe 0000:04:00.1 eth7: detected SFP+: 5
[20715.151574] ixgbe 0000:04:00.1 eth7: NIC Link is Up 10 Gbps, Flow
Control: RX/TX
[20715.151719] IPv6: ADDRCONF(NETDEV_CHANGE): eth7: link becomes ready