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If I got this feature correctly, this > feature permits the user consumes the data out of order when RDMA Write > and Send operations. But its completiong ordering is still in order. > Correct. > Any scenario that this feature can be applied and what benefits will be > got from this feature? > > I am just curious about this. Normally the users will consume the data > in order. In what scenario, the user will consume the data out of order? > One of the main benefits of this feature is achieving higher bandwidth (BW) by allowing responders to receive packets out of order (OOO). For example, this can be utilized in devices that support multi-plane functionality, as introduced in the "Multi-plane support for mlx5" series [1]. When mlx5 multi-plane is supported, a single logical mlx5 port aggregates multiple physical plane ports. In this scenario, the requester can "spray" packets across the multiple physical plane ports without guaranteeing packet order, either on the wire or on the receiver (responder) side. With this approach, no barriers or fences are required to ensure in-order packet reception, which optimizes the data path for performance. This can result in better BW, theoretically achieving line-rate performance equivalent to the sum of the maximum BW of all physical plane ports, with only one QP. [1] https://lore.kernel.org/lkml/cover.1718553901.git.leon@kernel.org/ > Thanks, > Zhu Yanjun > >> >> Thanks >> >> Edward Srouji (2): >>    net/mlx5: Introduce data placement ordering bits >>    RDMA/mlx5: Support OOO RX WQE consumption >> >>   drivers/infiniband/hw/mlx5/main.c    |  8 +++++ >>   drivers/infiniband/hw/mlx5/mlx5_ib.h |  1 + >>   drivers/infiniband/hw/mlx5/qp.c      | 51 +++++++++++++++++++++++++--- >>   include/linux/mlx5/mlx5_ifc.h        | 24 +++++++++---- >>   include/uapi/rdma/mlx5-abi.h         |  5 +++ >>   5 files changed, 78 insertions(+), 11 deletions(-) >> >