Configuring Relative Strict-Priority Scheduling for Aggregate Shaping Rates
To configure relative strict priority scheduling for aggregate shaping rates:
- Create a scheduler profile for the strict-priority queue.
- host1(config)# scheduler-profile relativeStrict
- host1(config-scheduler-profile)# shaping-rate 500000
- host1(config-scheduler-profile)# weight 0
- host1(config-scheduler-profile)# exit
Configuring the weight of 0 reduces latency and jitter.
- Create a scheduler profile for the nonstrict best-effort
queue.
- host1(config)# scheduler-profile be
- host1(config-scheduler-profile)# shaping-rate 1000000 burst 1
- host1(config-scheduler-profile)# weight 8
- host1(config-scheduler-profile)# exit
Tip: If you need to impose a shaping rate on the nonstrict queues to meet a functional requirement, you can specify a rate less than the aggregate rate. The key is that the burst size must be one, or small. The burst size determines the maximum-sized packet that can squeeze in front of a relative strict-priority packet in the round robin.
- Create a scheduler profile for the aggregate bandwidth.
- host1(config)#scheduler-profile vcAggregate
- host1(config-scheduler-profile)#shaping-rate 1000000
- host1(config-scheduler-profile)#exit
- Create a QoS profile, configure node shaping for each
queue, and add each of the queues to the QoS profile.
- host1(config)# qos-profile relative-strict-aggregate
- host1(config-qos-profile)# atm-vc node scheduler-profile vcAggregate
-
host1(config-qos-profile)# atm-vc
queue traffic-class best-effort
scheduler-profile be - host1(config-qos-profile)# atm-vc queue traffic-class voice scheduler-profile relativeStrict
- host1(config-qos-profile)# exit
- host1(config)#
This configuration creates the hierarchy shown in Figure 1.
Figure 1: Sample Relative Strict-Priority Scheduler Hierarchy
