Intel x520 10G card throughput

  • Hello,

    I have a machine running latest pfSense with an Intel x520 card installed on a PCIe x8 slot. I could never get near line rate throughput from the card. Throughput is somewhat limited to ~2.5Gbps. My understanding is that I am hitting the limitation of PCIe slot. Here is what dmesg reports:

    # dmesg | grep ix0
    ix0: <intel(r) pro="" 10gbe="" pci-express="" network="" driver,="" version="" -="" 2.5.15="">port 0xfcc0-0xfcdf mem 0xd8e80000-0xd8efffff,0xd8ff8000-0xd8ffbfff irq 36 at device 0.0 on pci1
    ix0: Using MSIX interrupts with 9 vectors
    ix0: Ethernet address: b8:ca:3a:6a:f2:40
    ix0: PCI Express Bus: Speed 5.0GT/s Width x8</intel(r)> 

    Also most of the cards that I am familiar with are supposed to be installed on a PCIe x8 and I am not sure if switching to another card will solve my throughput issue.

    I was wondering if people on this forum could share their success stories with other (or the same) 10G cards.


  • What kind of Intel x520 card is this exactly?
    Intel x520-DA2
    Intel x520-SR2
    Intel x520-T2

  • It say "Intel X520 DP 10Gb SR/SFP+, +I350 DP 1Gb Daughter Card with SR Optics"

  • PCIE 2.0 8x is good for 4,000MB/s, which is 32Gb/s. Plenty of bandwidth.

    What does your network look like for the flows? You mentioned you have a dual port i350.

    edit GB -> MB

  • Actually the card is a combo (dual 10G + dual 1G). Network throughput never exceeds 2.5Gbps (600Kpps) while CPUs are not saturated (up to 25% utilization).

  • ix0: PCI Express Bus: Speed 5.0GT/s Width x8

    So perhaps the Intel NIC is not able to use the given maximum from 2 x 10 GBit/s and 2 x 1 GBit/s.

    But you could this test out by using a server stress test tool like the one from PRTGs website
    this would be suficent to produce some really hardcore traffic and you will be able to see
    how the NIC is acting on this stress test perhaps also a good test to see whats your pfSense
    hardware is able to perform. Here is the link: Webserver Stress Tool
    In the upper right corner you are able to switch to the English language.

Log in to reply