We use 82599 ixgbe NIC. Driver version is 3.19.1. Because we use user space SCTP stack. It can't use checksum offloading feature. I modify the driver code skip skb->ip_summed check. Because we use ip raw socket, sk_buff hasn't transport head ptr. I add ip head length to Transmit Context Descriptor (TDESC). At last our user space SCTP stack can use checksum offloading feature.
But I find it only can transmit 120k pps SCTP packet(MTU 1500). It seems HW checksum offloading leading lots of time delay. Please give some advice.