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Overview
Overview
The SAP Egress policy defines the Service Level Agreement (SLA) for service packets as they
egress on the SAP. Egress SAP QoS policies allow the definition of queue parameters along with
remark policy. SAP egress policies and queues are supported for SAPs configured on access ports
and hybrid ports.
By default, the system allocates and associates "8" queues for use by each SAP created in the
system. The system predefines the FC to queue map. Each queue must have a CIR rate, PIR rate,
and a 'cir-level'. The pir-level of the queue is assigned by the system based on the cir-level
configured by the user. The CIR rate determines the amount of committed bandwidth to be made
available to this queue. The PIR rate forces a hard limit on the packets transmitted through the
queue. The hardware does not support a linear range of values for the rate parameters (both cir and
pir). The user can specify the computation method of rates to match the rates supported by the
hardware, through Adaptation-rules.
Each queue is also associated with a scheduler. The scheduler uses the queues cir and pir rate, cir-
level, pir-level and pir-weight to distribute the available bandwidth among the queues. When
multiple queues are in use, the level parameter determines the scheduling order of the queues.
Queues with higher value of level parameter are scheduled out first.
A queue-management policy can be associated with a queue to manage the buffer allocation for in-
profile and out-of profile packets. Note: Only a remark policy of type 'dot1p-only' or 'dot1p-lsp-
exp-shared' is available for use with SAP Egress policy.
The following table shows the default FC to queue map assigned by the system.
Table 38: FC to Queue Map
FC
NC
H1
EF
H2
L1
AF
L2
BE
NOTE: For more information on service egress scheduling, refer to the "QoS Schedulers" section.
Page 330
Queue Number
Queue #8
Queue #7
Queue #6
Queue #5
Queue #4
Queue #3
Queue #2
Queue #1
7210 SAS-X and 7210 SAS-R6 OS Quality of Service Guide
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