2 Replies Latest reply on Jun 5, 2018 7:13 AM by blackwall

    How does the switch forward packets sharing the same traffic class value?



      In RoCEv2,  NICs and switches support classifying traffics according to their DSCP value in IP header.

      Then traffics can be enqueued into different hardware traffic classes(actually hardware queue).

      The DSCP-to-TrafficClass mapping rule is as following:

      • DSCP values are mapped to priorities
      • Priorities are mapped to Traffic Class (tc)


      So there are multiple DSCP values that are mapped into the same hardware queue.

      So what will switch process these traffics enqueued into the same hardware queue? FIFO or small DSCP first?

      I have looked through the official docs such as MLNX_OFED_Linux_User_Manual and MLNX_OS_Ethernet_User_Manual, but haven't found any detailed content.

      Can someone help me?