A QoS Policy for InfiniBand

InfiniBand is a state-of-the-art high performance networking technology used in many of the worlds largest super computers and in datacenters where high bandwidth and low latency is required. InfiniBand supports quality of service with a flexible traffic differentiation mechanism, but no good guidelines or policies for using QoS in InfiniBand exists.

Latency as a function of network load for five different service levels (SL 1-5).

Traffic differentiation applies differential treatment to traffic in order to provide certain guarantees to particular streams. A complex application e.g. a video server deals with a multitude of traffic types, each with different requirements to timely delivery. Some of the traffic may be sensitive to delay but without strict bandwidth requirements, for example, network control and management traffic. Other types of traffic e.g video streams, may have strict bandwidth requirements whereas the latency requirements are relaxed. In InfiniBand networks the OpenFabics Enterprise Distribution (OFED) and OpenSM is the system software required to configure and implement QoS. OpenSM has only recently gained support for QoS, and there is now demand for a general policy for the QoS features supported by IBA. This includes setting the different IBA tables, SL selection for the different protocols supported by the stack, how to combine different applications, how to deal with various number of VLs etc. The purpose of the thesis is to suggest and evaluate a QoS policy for InfiniBand with OpenSM/OFED.

What you will do:
  • You will suggest, analyse, and evaluate a QoS policy for InfiniBand
  • You will make performance measurements on real hardware
  • You will configure and maybe extend QoS features in OpenSM and the OFED software stack
  • Potentially publish your results at a scientific venue!
What you will learn:
  • You will get to know the InfiniBand architecture, a state of the art high performance networking technology.
  • You will obtain a thorough understanding of the OpenSM software and the OFED stack.
  • You will learn to analyse network performance.


  • Network experience
  • Programming experience
For more information, please contact Sven-Arne Reinemo (svenar@simula.no)
Emneord: Quality of Service, InfiniBand, Interconnection Networks, Super Computers
Publisert 4. sep. 2015 16:19