User Manual

OpenSM – Subnet ManagerRev 2.2-1.0.1
Mellanox Technologies
206
Note that any of the above ULPs might contain target port GUID in the PR query, so in order for
these queries not to be recognized by the QoS manager as SRP, the SRP match rule (or any match
rule that refers to the target port guid only) should be placed at the end of the qos-ulps match
rules.
8.6.6.5 MPI
SL for MPI is manually configured by MPI admin. OpenSM is not forcing any SL on the MPI
traf
fic, and that's why it is the only ULP that did not appear in the qos-ulps section.
8.6.7 SL2VL Mapping and VL Arbitration
OpenSM cached options file has a set of QoS related configuration parameters, that are used to
configure SL2VL mapping and VL arbitration on IB ports. These parameters are:
Max VLs: the maximum number of VLs that will be on the subnet
High limit: the limit of High Priority component of VL Arbitration table (IBA 7.6.9)
VLArb low table: Low priority VL Arbitration table (IBA 7.6.9) template
VLArb high table: High priority VL Arbitration table (IBA 7.6.9) template
SL2VL: SL2VL Mapping table (IBA 7.6.6) template. It is a list of VLs corresponding
to SLs 0-15 (Note that
VL15 used here means drop this SL).
There are separate QoS configuration parameters sets for various target types: CAs, routers,
switch external ports, and switch's enhanced port 0.
The names of such parameters are prefixed
by "qos_<type>_" string. Here is a full list of the currently supported sets:
qos_ca_ - QoS configuration parameters set for CAs.
qos_rtr_ - parameters set for routers.
qos_sw0_ - parameters set for switches' port 0.
qos_swe_ - parameters set for switches' external ports.
Here's the example of typical default values for CAs and switches' external ports (hard-coded in
OpenSM initialization):
qos_ca_max_vls 15
qos_ca_high_limit 0
qos_ca_vlarb_high 0:4,1:0,2:0,3:0,4:0,5:0,6:0,7:0,8:0,9:0,10:0,11:0,12:0,13:0,14:0
qos_ca_vlarb_low 0:0,1:4,2:4,3:4,4:4,5:4,6:4,7:4,8:4,9:4,10:4,11:4,12:4,13:4,14:4
qos_ca_sl2vl 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,7
qos_swe_max_vls 15
qos_swe_high_limit 0
qos_swe_vlarb_high 0:4,1:0,2:0,3:0,4:0,5:0,6:0,7:0,8:0,9:0,10:0,11:0,12:0,13:0,14:0
qos_swe_vlarb_low 0:0,1:4,2:4,3:4,4:4,5:4,6:4,7:4,8:4,9:4,10:4,11:4,12:4,13:4,14:4
qos_swe_sl2vl 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,7
VL arbitration tables (both high and low) are lists of VL/Weight pairs. Each list entry contains a
VL number (values from 0-14), and a weighting value (values 0-255), indicating the number of
64 byte units (credits) which may be transmitted from that VL when its turn in the arbitration
occurs. A weight of 0 indicates that this entry should be skipped. If a list entry is programmed for
VL15 or for a VL that is not supported or is not currently configured by the port, the port may
either skip that entry or send from any supported VL for that entry.