D-Link DGS-6600-48T Product Manual - Page 503

DGS-6604 m Examples qos deficit-round-robin All queues are serviced until their credit counter is zero or negative and a packet is transmitted completely. As this condition happens, the credits are replenished. When the credits are replenished, as a quantum of credits are added to each CoS queue credit counter. The quantum for each CoS queue may different based on the user configuration. To set a CoS in strict priority mode, any higher priority CoS must be in strict priority mode. For example, to set CoS 5 in strict priority mode, CoS 6 and 7 have to be in strict priority mode. WRR operates by transmitting permitted packets into the transmit queue in round robin order. Initially, each queue sets its weight to a configurable weighting. Every time a packet from a higher priority CoS queue is sent, the number of the packet is subtracted from the corresponding weight. When the credit counter reaches zero, the queue is no longer serviced until its weight is replenished. After this repeats for each queue, the next lower priority CoS queue is serviced in turn. All queues are serviced until their weight is zero and a packet is transmitted completely. As this condition happens, the weights are replenished. When the weights are replenished, weight is added to each CoS queue credit counter. The weight for each CoS queue may different based on the user configuration. In the following example, deficit round robin is configured on eth 3.1. For this case, quantum for queue 0 is set to 32 Kbytes; quantum for queue 1 is set to 32 Kbytes; quantum for queue 2 is set to 64 Kbytes; quantum for queue 3 is set to 64 Kbytes; quantum for queue 4 is set to 128 Kbytes; quantum for queue 5 is set to 128 Kbytes; quantum for queue 6 is set to 32 Kbytes; and quantum for queue 7 remains as 0. Switch(config)# interface eth3.1 Switch(config-if)# qos deficit-round-robin 0 quantum 2 Switch(config-if)# qos deficit-round-robin 1 quantum 2 Switch(config-if)# qos deficit-round-robin 2 quantum 4 Switch(config-if)# qos deficit-round-robin 3 quantum 4 Switch(config-if)# qos deficit-round-robin 4 quantum 8 Switch(config-if)# qos deficit-round-robin 5 quantum 8 Switch(config-if)# qos deficit-round-robin 6 quantum 2 Switch(config-if)# qos deficit-round-robin 7 quantum 0 CLI Reference Guide 493