Queueing And Scheduling On Egress Queues - Cisco Catalyst 2975 Software Configuration Manual

Chapter 33 Configuring QoS
Understanding QoS
SRR services the priority queue for its configured weight as specified by the bandwidth keyword in the
mls qos srr-queue input priority-queue queue-id bandwidth weight global configuration command.
Then, SRR shares the remaining bandwidth with both ingress queues and services them as specified by
the weights configured with the mls qos srr-queue input bandwidth weight1 weight2 global
configuration command.
You can combine the commands described in this section to prioritize traffic by placing packets with
particular DSCPs or CoSs into certain queues, by allocating a large queue size or by servicing the queue
more frequently, and by adjusting queue thresholds so that packets with lower priorities are dropped. For
configuration information, see the "Configuring Ingress Queue Characteristics" section on page 33-63.

Queueing and Scheduling on Egress Queues

Figure 33-8 shows the queueing and scheduling flowchart for egress ports.
If the expedite queue is enabled, SRR services it until it is empty before servicing the other three queues.
Note
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