Intel® Ethernet 800 Series Linux Flow Control

Configuration Guide for RDMA Use Cases

ID Date Version Classification
635330 11/13/2025 Public
Document Table of Contents

Separating and Prioritizing Traffic Streams

For networks carrying multiple traffic types, you typically want:

  • One loss-less (no-drop) TC for RDMA traffic.
  • One or more lossy (drop) TCs for LAN traffic.

This can change depending on specific applications.

Example configuration:

Traffic Stream Loss-less TC Priority Bandwidth
RDMA Traffic Yes 0 0 50%
LAN Application #1 No 1 2 25%
LAN Application #2 No 2 4 25%
Unused No Any1 All Others1 None
Notes:
  1. Unused priorities can be mapped to any TC (no traffic is being steered to specific priorities). Leaving them mapped to TC 0 is acceptable.
Notes:
  • For NICs with four or fewer ports, the 800 Series adapters support up to eight Traffic Classes (TCs) per port. For NIC with more than four ports, the number of supported TCs is limited to four per interface.
  • Traffic classes must start at zero and must be contiguous (0, 1, 2, 3, ... ).
  • ETS bandwidth allocations must total 100%.
  • Multiple priorities might map to the same TC. For example, TC0 can contain prio=0,1,2,3,4,5,6,7. However, a given priority might map to only a single TC (like prio 0 cannot be in both TC0 and TC1).