User Manual

Features Overview and ConfigurationRev 2.3-1.0.1
Mellanox Technologies
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the policy, so clients (ULPs, programs) can obtain a policy enforced QoS. The SM may also
set up partitions with appropriate IPoIB broadcast group. This broadcast group carries its QoS
attributes: SL, MTU, RATE, and Packet Lifetime.
3. IPoIB is being setup. IPoIB uses the SL, MTU, RATE and Packet Lifetime available on the
multicast group which forms the broadcast group of this partition.
4. MPI which provides non IB based connection management should be configured to run using
hard coded SLs. It uses these SLs for every QP being opened.
5. ULPs that use CM interface (like SRP) have their own pre-assigned Service-ID and use it
while obtaining PathRecord/MultiPathRecord (PR/MPR) for establishing connections.
The
SA receiving the PR/MPR matches it against the policy and returns the appropriate PR/MPR
including SL, MTU, RATE and Lifetime.
6. ULPs and programs (e.g. SDP) use CMA to establish RC connection provide the CMA the
tar
get IP and port number. ULPs might also provide QoS-Class. The CMA then creates Ser-
vice-ID for the ULP and passes this ID and optional QoS-Class in the PR/MPR request. The
resulting PR/MPR is used for configuring the connection QP
.
PathRecord and MultiPathRecord Enhancement for QoS:
As mentioned above, the PathRecord and MultiPathRecord attributes are enhanced to carry the
Service-ID which is a 64bit value. A new field QoS-Class is also provided.
A new capability bit describes the SM QoS support in the SA class port info. This approach pro-
vides an easy migration path for existing access layer and ULPs by not introducing new set of
PR/MPR attributes.
3.2.3.2 Supported Policy
The QoS policy, which is specified in a stand-alone file, is divided into the following four sub-
sections:
Port Group
A set of CAs, Routers or Switches that share the same settings. A port group might be a partition
defined by the partition manager policy
, list of GUIDs, or list of port names based on NodeDe-
scription.
Fabric Setup
Defines how the SL2VL and VLArb tables should be setup.
In OFED this part of the policy is ignored. SL2VL and VLArb tables should be config-
ured in the OpenSM options file (opensm.opts).
QoS-Levels Definition
This section defines the possible sets of parameters for QoS that a client might be mapped to.
Each set holds SL and optionally: Max MTU, Max Rate, Packet Lifetime and Path Bits.