Cross Channel is a Verbs API that enables one to define a list of communication tasks and synchronization points and post this list as a single WQE which the HCA progresses entirely. Once posted, only completion of the list is polled for by the CPU. In this way, one can create and schedule complex communication and coordination patterns among all nodes in a cluster.

Cross Channel Experimental Verbs

• ibv_exp_post_task
• ibv_exp_create_qp
  • IBV_EXP_QP_CREATE_CROSS_CHANNEL
  • IBV_EXP_QP_CREATE_MANAGED_SEND
  • IBV_EXP_QP_CREATE_MANAGED_RECV
  • IBV_EXP_QP_CREATE_IGNORE_SQ_OVERFLOW
  • IBV_EXP_QP_CREATE_IGNORE_RQ_OVERFLOW
• Ibv_exp_create_cq
  • IBV_EXP_CQ_CREATE_CROSS_CHANNEL
• Ibv_exp_modify_cq
  • IBV_EXP_CQ_IGNORE_OVERRUN
• Ibv_exp_post_send
  • union task
  • ibv_exp_calc_op
  • ibv_exp_calc_data_type
  • ibv_exp_calc_data_size
  • IBV_EXP_WR_SEND_ENABLE
  • IBV_EXP_WR_RECV_ENABLE
  • IBV_EXP_WR_CQE_WAIT
• ibv_exp_query_device
  • calc_cap

Cross Channel Experimental Capabilities and Device Attributes

• IBV_EXP_DEVICE_CROSS_CHANNEL
• IBV_EXP_DEVICE_ATTR_CALC_CAP

Cross Channel RDMA-Core Support