Cisco WS-C3750-48PS-S Software Configuration Manual page 685

Chapter 32 Configuring QoS
Beginning in privileged EXEC mode, follow these steps to configure the memory allocation and to drop
thresholds for a queue-set. This procedure is optional.
Command
Step 1 configure terminal
Step 2 mls qos queue-set output qset-id
buffers allocation1 ... allocation4
Step 3 mls qos queue-set output qset-id
threshold queue-id drop-threshold1
drop-threshold2 reserved-threshold
maximum-threshold
Step 4
interface interface-id
Step 5
queue-set qset-id
78-16180-02
Purpose
Enter global configuration mode.
Allocate buffers to a queue-set.
By default, all allocation values are equally mapped among the four
queues (25, 25, 25, 25). Each queue has 1/4 of the buffer space.
• For qset-id, enter the ID of the queue-set. The range is 1 to 2. Each
port belongs to a queue-set, which defines all the characteristics of the
four egress queues per port.
For allocation1 ... allocation4, specify four percentages, one for each
•
queue in the queue-set. For allocation1, allocation3, and allocation4,
the range is 0 to 99. For allocation2, the range is 1 to 100 (including
the CPU buffer).
Allocate buffers according to the importance of the traffic; for example,
give a large percentage of the buffer to the queue with the highest-priority
traffic.
Configure the WTD thresholds, guarantee the availability of buffers, and
configure the maximum memory allocation for the queue-set (four egress
queues per port).
By default, the WTD thresholds for queues 1, 3, and 4 are set to 100
percent. The thresholds for queue 2 are set to 50 percent. The reserved
thresholds for queues 1, 3, and 4 are set to 50 percent. The reserved
threshold for queue 2 is set to 100 percent. The maximum thresholds for
all queues are set to 400 percent.
For qset-id, enter the ID of the queue-set specified in Step 2. The
•
range is 1 to 2.
For queue-id, enter the specific queue in the queue-set on which the
•
command is performed. The range is 1 to 4.
For drop-threshold1 drop-threshold2, specify the two WTD
•
thresholds expressed as a percentage of the queue's allocated
memory. The range is 1 to 400 percent.
For reserved-threshold, enter the amount of memory to be guaranteed
•
(reserved) for the queue expressed as a percentage of the allocated
memory. The range is 1 to 100 percent.
For maximum-threshold, enable a queue in the full condition to obtain
•
more buffers than are reserved for it. This is the maximum memory
the queue can have before the packets are dropped if the common pool
is not empty. The range is 1 to 400 percent.
Specify the port of the outbound traffic, and enter interface configuration
mode.
Map the port to a queue-set.
For qset-id, enter the ID of the queue-set specified in Step 2. The range is
1 to 2. The default is 1.
Catalyst 3750 Switch Software Configuration Guide
Configuring Standard QoS
32-61