I have an Intel 10Gbps card that has the 82599 10GbE Controller. The card has two ports in it. The datasheet of the controller says it supports PCIe 2.0 (2.5 GT/s or 5.0 GT/s)
Now, according to PCIe SIG's faq page (link: https://www.pcisig.com/news_room/faqs/pcie3.0_faq/#EQ3) says that for a 5.0 GT/s symbol rate PCIe gives an interconnect bandwidth of 4Gbps and a per lane per direction of 500MB/s)
I ran a netperf test on the card (I connected two of these cards via OFC back-to-back with no switches in-between) and the bandwidth of around 3.3Gbps (which is around 400MB/s)
Is my card under-utilized or does those numbers add up? Why wouldn't I get a full 10Gbps on the card (and only get 3.3Gbps)
(The card is x4 on an x8 slot)
Update: The network card goes to a slot that is configured as PCIe 3.0 and its an x8 slot (it supports upto 8.0 GT/s). And as to the board itself, well its a Freescale board (Processor: T4240). So I figured that board might be ok, with the card being slower of the two.
Thanks in advance.