Avaya P580 - Manual (Page 681)

Avaya P550R, P580, P880, and P882 Multiservice Switch User Guide, v5.3.1 -35
80-Series QoS
Queue-Servicing Algorithms
The following queue-servicing algorithms are available for egress
queues:
■
Weighted fair queueing (WFQ)
■
Strict Priority
■
Class-based queueing (CBQ)
■
Class-based weighted fair queueing (CBWFQ)
* Note: In earlier versions of the switch software, you could set
ingress queues to use the weighted fair queuing (WFQ)
and strict priority queue-servicing algorithms. In v5.3.1,
you can set only egress queues to use these queue-
servicing algorithms. To service ingress queues, use the
policing feature.
WFQ
How WFQ
Works
WFQ is the default queue-servicing algorithm. When a port is set to
use the WFQ algorithm, each queue:
■
Is assigned a weight increment. This value never changes.
■
Maintains an accumulated weight. After the switch services a
queue, its accumulated weight is reset to the value of its weight
increment, and the accumulated weight for the other queues is
increased by their respective weight increments.
The switch always services the queue that has the highest
accumulated weight. If two queues have the same accumulated
weight, the switch first services the queue that has the highest
priority (0 – 7).
Table 6-156 lists the default weight increment for each queue.
Table 6-156. Default Weight Increments
Queue Weight Increment
WFQ 0 1
WFQ 1 2
WFQ 2 4
1 of 2