We have i40e driver on the Host and i40e dpdk pmd on the vm guest. We have 25G 2 port Nic fortville card.
We are seeing performance degradation when we use both the ports on a nic. We can do only 20G when both the ports are used and can push it to 23G when only one port in a nic is used.
Intel DPDK documentations says use the DPDK config CONFIG_RTE_LIBRTE_I40E_16BYTE_RX_DESC if we need to drive both ports on a nic. The problem is there is no way of setting 16 byte descriptor on the Guest PMD and host i40e driver simultaneously. So we couldnt use the 16 byte descriptors.
Is there a way to do this?