2 Replies Latest reply on Dec 13, 2018 12:40 AM by blackwall

    How can I get the statistics of DCQCN in CX5 Cards?



      I was configuring the DCQCN parameters on 100Gbps CX5 cards and ECN thresholds on the Mellanox SN2100 switch.

      After I ran some tests(randomly write data from one server to the other server), How could I know if the DCQCN was running during the tests? (equally, could I check the generated/received CNP packets on the server?)

      After reading the relevant document HowTo Configure DCQCN (RoCE CC) values for ConnectX-4 (Linux) , I got that the default DSCP value is 48 and the default priority is 6 of CNP packets. (Check the path "/sys/kernel/debug/mlx5/cc_parameters/*")

      So I can check the packets counters by using `ethtool -S p4p1 | grep "rx_prio6_packets"`, the result was similar to the following figure:

      It showed that packets did occur on the 6th priority tx/rx queue. But how could I identify which packets are CNP packets?

      Are there another methods to monitor the CNP packets or other parameters of DCQCN?