HP 6125G HP 6125G & 6125G/XG Blade Switches ACL and QoS Configuration - Page 47

Figure 15 SP queuing Packets to be sent through this port Queue 7 Queue 6 Packet classification ...... Queue 1 Queue 0 High priority Sent packets Interface Queue Sending queue scheduling Low priority In Figure 15, SP queuing classifies eight queues on a port into eight classes, numbered 7 to 0 in descending priority order. SP queuing schedules the eight queues in the descending order of priority. SP queuing sends packets in the queue with the highest priority first. When the queue with the highest priority is empty, it sends packets in the queue with the second highest priority, and so on. You can assign mission-critical packets to the high priority queue to make sure that they are always served first, and assign common service packets to the low priority queues and transmitted when the high priority queues are empty. The disadvantage of SP queuing is that packets in the lower priority queues cannot be transmitted if packets exist in the higher priority queues. This may cause lower priority traffic to starve to death. WRR queuing WRR queuing schedules all the queues in turn to ensure every queue is served for a certain time, as shown in Figure 16. Figure 16 WRR queuing 41