How to config mellanox cx5 to make ack generated when rdma writting each fragment packet

Infrastructure & Networking Software And Drivers Mellanox OFED
1

data with its size larger than mtu，the host will rdma-write fragments to the remote(mellanox cx5)，but the remote not reply an ack to each fragment . it cause the number of acks and fragments is not equal .How do I configure the remote so that it reply an ack to each fragment？

2

Hi,

You can try the following:

  1. Configure the socket option TCP_NODELAY in the application that uses RDMA.

  2. Adjust the MTU size to a value that minimizes fragmentation. If possible, enable jumbo frames (9000 bytes) if your network supports it.

  3. Use the ibv_modify_qp API to configure specific QP attributes that control packet transmission and acknowledgment behavior.

  4. f you’re using RoCE, ensure ECN is properly configured to help with congestion management.

Regards,
Chen