JUNOSe 9.1.x Quality of Service Configuration Guide > Configuring Strict-Priority Scheduling > Configuring Relative Strict-Priority Scheduling for Aggregate Shaping Rates

Configuring Relative Strict-Priority Scheduling for Aggregate Shaping Rates

To configure relative strict priority scheduling for aggregate shaping rates:

1. 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.

2. 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. 



 

3. 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

4. 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 16.

Figure 16: Sample Relative Strict-Priority Scheduler Hierarchy

Related Topics

• Strict-Priority and Relative Strict-Priority Scheduling Overview
• For more information about specifying an expression that you can reference within a scheduler profile, see Using Expressions for Bandwidth and Burst Values in a Scheduler Profile
• node command
• qos-profile command
• scheduler-profile command
• shaping-rate command
• weight command