D-Link DGS-6600-48T Product Manual - Page 502

DGS-6604 m qos deficit-round-robin qos deficit-round-robin Use the qos command in interface configuration mode to enable the Deficit Round Robin (DRR)/Weighted Round Robin (WRR) packet scheduling mechanism. To restore the packet scheduling mechanism, use the default form of this command. qos {deficit-round-robin [COS-QUEUE quantum WEIGHT] |weight-round-robin [COS-QUEUE weight WEIGHT]} default qos Syntax Description deficit-round-robin deficit-round-robin in interface configuration mode to enable the Deficit Round Robin (DRR) packet scheduling mechanism weight-round-robin weight-round-robin in interface configuration mode to enable the weighted Round Robin (WRR) packet scheduling mechanism COS-QUEUE The transmit priority queue; valid value is from 0 to 7. quantum WEIGHT (Optional) Specifies the Deficit Round Robin (DRR) quantum weight from 0 to 255. The final quantum is 16Kbytes * WEIGHT. The number of zero stands for strict priority mode. weight WEIGHT (Optional) Specifies the WRR weight. The final weight is number of permitted scheduling packets.Tthe range is 0 ~ 15 and the number of zero stands for strict priority mode. Default Command Mode Usage Guideline Strict priority mode and DRR mode is disabled. quantum WEIGHT: 1 wrr-WEIGHT: 1 Interface configuration Only physical port interfaces are valid for this command. The port CoS queue can be either strict priority mode, deficit round robin (DRR)mode or Weight round robin (WRR) mode. The strict priority scheduler mode provides strict priority access to the egress port across the transmit priority queue from the highest priority index to the lowest. The purpose of the strict priority scheduler is to provide lower latency service to the higher CoS classes of traffic. DRR operates by serving a mount of backlogged credits into the transmit queue in round robin order. Initially, each queue sets its credit counter to a configurable quantum value. Every time a packet from a CoS queue is sent, the size of the packet is subtracted from the corresponding credit counter. When the credit counter drops below 0, the queue is no longer serviced until its credits are replenished. CLI Reference Guide 492