Brocade Communications Systems 53-1001761-01 manual Scheduling the QoS queue

9	Scheduling
TABLE 19		Supported scheduling configurations
Traffic Class		SP0	SP1	SP2	SP3	SP4	SP5	SP6	SP8
7		WRR8	SP1	SP2	SP3	SP4	SP5	SP6	SP8
6		WRR7	WRR7	SP1	SP2	SP3	SP4	SP5	SP7
5		WRR6	WRR6	WRR6	SP1	SP2	SP3	SP4	SP6
4		WRR5	WRR5	WRR5	WRR5	SP1	SP2	SP3	SP5
3		WRR4	WRR4	WRR4	WRR4	WRR4	SP1	SP2	SP4
2		WRR3	WRR3	WRR3	WRR3	WRR3	WRR3	SP1	SP3
1		WRR2	WRR2	WRR2	WRR2	WRR2	WRR2	WRR2	SP2
0		WRR1	WRR1	WRR1	WRR1	WRR1	WRR1	WRR1	SP1

Figure 12 shows that extending the frame scheduler to a hybrid SP+WRR system is fairly straightforward. All SP queues are considered strictly higher priority than WRR so they are serviced first. Once all SP queues are drained, then the normal WRR scheduling behavior is applied to the non-empty WRR queues.

FIGURE 12 Strict priority and Weighted Round Robin scheduler

Scheduling the QoS queue

Perform the following steps from Privileged EXEC mode specify the schedule to use. 1. Enter global configuration mode.

switch#configure terminal

2. Specify the schedule to use and the traffic class to bandwidth mapping.

switch(config)#qos queue scheduler strict-priority 4 dwrr 10 20 30 40

Example of setting the traffic class frame scheduler for 4 Strict Priority Traffic Class and 4 DWRR Traffic Class with Traffic Class 0 getting 10 percent bandwidth, Traffic Class 1 getting 20 percent bandwidth, Traffic Class 2 getting 30 percent bandwidth, and Traffic Class 3 getting 40 percent bandwidth.

switch:admin>cmsh switch>enable

switch#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

switch(config)#qos queue scheduler strict-priority 4 dwrr 10 20 30 40 switch(config)#end

3. Enter the copy command to save the running-config file to the startup-config file.

switch#copy running-config startup-config

104	Converged Enhanced Ethernet Administrator’s Guide
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