SPRUGR9H November 2010 – April 2015 66AK2E05 , 66AK2H06 , 66AK2H12 , 66AK2H14 , 66AK2L06 , AM5K2E02 , AM5K2E04 , SM320C6678-HIREL , TMS320C6652 , TMS320C6654 , TMS320C6655 , TMS320C6657 , TMS320C6670 , TMS320C6671 , TMS320C6672 , TMS320C6674 , TMS320C6678
The basic building block of the QoS system is a QoS queue. Each queue represents a flow priority, flow rate, drop policy, and egress queue. (Different QoS algorithms may or may not make use of all these properties.) Queues with the same egress queue are grouped together into a queue cluster called a QoS cluster. A cluster can contain from one to nine QoS queues. Any of the 64 available QoS queues can be allocated into any given QoS cluster, although a queue may not belong to more than one cluster.
The QoS Queue Record format is shown in Table 4-57:
QoS Queue Offset | Field | |||
---|---|---|---|---|
Byte 3 | Byte 2 | Byte 1 | Byte 0 | |
0x00 | Iteration Credit | Egress Queue | ||
0x04 | Total Credit | |||
0x08 | Maximum Credit | |||
0x0C | Congestion Threshold | |||
0x10 | Packets Forwarded | |||
0x14 | Packets Dropped |
Table 4-58 shows the breakdown of each field:
Field | Byte Width | Notes |
---|---|---|
Egress Queue | 2 | The Queue number of the forwarding queue. |
Iteration Credit | 2 | The amount of forwarding byte credit that the queue receives every 25 µs. |
Total Credit | 4 | The total amount of forwarding byte credit the that queue is currently holding. |
Maximum Credit | 4 | The maximum amount of forwarding byte credit that the queue is allowed to hold at the end of the timer iteration. Any credit over the maximum limit is added to a global pool. |
Congestion Threshold | 4 | The size in bytes at which point the QoS queue is considered to be congested. |
Packets Forwarded | 4 | The number of packets forwarded to the Egress Queue. |
Packets Dropped | 4 | The number of packets dropped due to congestion. |