Priority-Queue - Cisco Catalyst 3120 Command Reference Manual

Chapter 2 Cisco Catalyst Blade Switch 3120 for HP Cisco IOS Commands

priority-queue

Use the priority-queue interface configuration command to enable the egress expedite queue on a port.
Use the no form of this command to return to the default setting.
Syntax Description
out
Defaults The egress expedite queue is disabled.
Command Modes
Interface configuration
Command History Release
12.2(40)EX
Usage Guidelines
When you configure the priority-queue out command, the shaped round robin (SRR) weight ratios are
affected because there is one fewer queue participating in SRR. This means that weight1 in the srr-queue
bandwidth shape or the srr-queue bandwidth shape interface configuration command is ignored (not
used in the ratio calculation). The expedite queue is a priority queue, and it is serviced until empty before
the other queues are serviced.
Follow these guidelines when the expedite queue is enabled or the egress queues are serviced based on
their SRR weights:
•
•
•
Examples
This example shows how to enable the egress expedite queue when the SRR weights are configured. The
egress expedite queue overrides the configured SRR weights.
Switch(config)# interface gigabitethernet1/0/2
Switch(config-if)# srr-queue bandwidth shape 25 0 0 0
Switch(config-if)# srr-queue bandwidth share 30 20 25 25
Switch(config-if)# priority-queue out
OL-12248-01
priority-queue out
no priority-queue out
Enable the egress expedite queue.
Modification
This command was introduced.
If the egress expedite queue is enabled, it overrides the SRR shaped and shared weights for queue 1.
If the egress expedite queue is disabled and the SRR shaped and shared weights are configured, the
shaped mode overrides the shared mode for queue 1, and SRR services this queue in shaped mode.
If the egress expedite queue is disabled and the SRR shaped weights are not configured, SRR
services the queue in shared mode.
Cisco Catalyst Blade Switch 3120 for HP Command Reference
priority-queue
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