AT-GS950/16PS Switch Web Interface User’s Guide

The problem with this method is that some low priority packets might never be transmitted from the switch because the algorithm might never have time to process the packets waiting in the lower priority queues.

Weighted Round Robin Priority Scheduling

The weighted round robin (WRR) scheduling method functions as its name implies. The port transmits a set number of packets from each queue, in a round robin fashion, so that each has a chance to transmit traffic.Normally, the higher the queue’s priority the more packets are transmitted in as the algorithm cycles through the queues in turn. This method guarantees that every queue receives some attention from the port for transmitting packets.

Table 5 shows the WRR settings for the number of packets transmitted from each queue. These values are permanent and you cannot be change these values.

Table 5. Example of Weighted Round Robin Priority

Port Egress Queue

Maximum Number of

Packets

 

 

 

 

 

Q3

8

 

 

Q2

4

 

 

Q1

2

 

 

Q0

1

 

 

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Allied Telesis AT-GS950/16PS, AT-S112 manual Weighted Round Robin Priority Scheduling, Port Egress Queue Maximum Number