Quality of Service (QoS)

Figure 2.1 illustrates a cycle through the queues.

 

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Queue 3: weight=4, minimum percentage=80%

Queue 2: weight=3, minimum percentage=15%

Queue 1: weight=2, minimum percentage=3.3%

Queue 0: weight=1, minimum percentage=1.7%

Figure 2.1 Example of a QoS cycle using the default weights

If you change the percentages for the queues, the software changes the weights, which changes the number of visits a queue receives during a full queue cycle and also the number of packets sent from each queue during each visit. For example, if you change the percentages so that queue qosp3 receives a weight of 5, then the system processes five packets in that queue during each visit to the queue.

NOTE: The weighted fair queuing method is based on packet-level scheduling. As a result, a queue’s bandwidth percentage does not necessarily reflect the exact bandwidth share the queue receives. This is due to the effects of variable size packets.

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