Hi Sagi, I've been trying to understand the isert functionality with respect to RDMA Receive Queue sizing and Queue full handling. Here is the problem is see with iw_cxgb4: After running few minutes of iSER traffic with iw_cxgb4, I am seeing post receive failures due to receive queue full returning -ENOMEM. In case of iw_cxgb4 the RQ size is 130 with qp attribute max_recv_wr = 129, passed down by isert to iw_cxgb4.isert decides on max_recv_wr as 129 based on (ISERT_QP_MAX_RECV_DTOS = ISCSI_DEF_XMIT_CMDS_MAX = 128) + 1. My debug suggests that at some point isert tries to post more than 129 receive WRs into the RQ and fails as the queue is full already. From the code most of the recv wr are posted only after a recieve completion, but few datain operations(isert_put_datain()) are done independent of receive completions. In fact the last WR failed to post in to RQ is from isert_put_datain() through target_complete_ok_work(). CQ stats at the time of failure shows the cq polled to empty. How could I check for the possible conditions leading to this issue? I am happy to provide you any details further. Thanks for your time. Bharat. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
