Brocade Converged Enhanced Ethernet Administrator's Guide v6.1.2_cee (53-1001258-01, June 2009)

116 Converged Enhanced Ethernet Administrator’s Guide
53-1001258-01
Scheduling
8
When you configure the QoS queue to use strict priority 4 (SP4), then traffic class 7 will use SP4,
traffic class 6 will use SP3, and so on down the list. You use the strict priority mappings to control
how the different traffic classes will be routed in the queue.
Figure 11 shows that extending the packet 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 11 Strict priority and Weighted Round Robin scheduler
Scheduling the QoS queue
Example of setting the traffic class packet scheduler for 4 Strict Priority Traffic Class and 4 DWRR Traffic Class with Traffic Class
0 getting 10% bandwidth, Traffic Class 1 getting 20% bandwidth, Traffic Class 2 getting 30% bandwidth, and Traffic Class 3
getting 40% 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)#exit
switch#
TABLE 20 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
Step Task Command
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