Hierarchical Schedulers and Traffic Control Profiles
When used, the interface set level of the hierarchy falls between the physical interface level (Level 1) and the logical interface (Level 3). Queues are always the highest level of the hierarchy. Certain devices and line cards support up to five levels of scheduler hierarchies. The concepts presented in this topic apply similarly to five scheduler hierarchy levels.
Hierarchical schedulers add CoS parameters to the interface-set level of the configuration. They use traffic control profiles to set values for parameters such as shaping rate (the peak information rate [PIR]), guaranteed rate (the committed information rate [CIR] on these interfaces), scheduler maps (assigning queues and resources to traffic), and so on.
The following CoS configuration places the following parameters in traffic control profiles at various levels:
Traffic control profile at the port level (
tcp-port-level1):A shaping rate (PIR) of 100 Mbps
A delay buffer rate of 100 Mbps
Traffic control profile at the interface set level (
tcp-interface-level2):A shaping rate (PIR) of 60 Mbps
A guaranteed rate (CIR) of 40 Mbps
Traffic control profile at the logical interface level (
tcp-unit-level3):A shaping rate (PIR) of 50 Mbps
A guaranteed rate (CIR) of 30 Mbps
A scheduler map called
smap1to hold various queue properties (level 4)A delay buffer rate of 40 Mbps
In this case, the traffic control profiles look like this:
[edit class-of-service traffic-control-profiles]
tcp-port-level1 { # This is the physical port level
shaping-rate 100m;
delay-buffer-rate 100m;
}
tcp-interface-level2 { # This is the interface set level
shaping-rate 60m;
guaranteed-rate 40m;
}
tcp-unit-level3 { # This is the logical interface level
shaping-rate 50m;
guaranteed-rate 30m;
scheduler-map smap1;
delay-buffer-rate 40m;
}
Once configured, the traffic control profiles must be applied to the proper places in the CoS interfaces hierarchy.
[edit class-of-service interfaces]
interface-set level-2 {
output-traffic-control-profile tcp-interface-level-2;
}
ge-0/1/0 {
output-traffic-control-profile tcp-port-level-1;
unit 0 {
output-traffic-control-profile tcp-unit-level-3;
}
}
In all cases, the properties for level 4 of the hierarchical schedulers (the queues) are determined by the scheduler map.