Alcatel-Lucent 7950 Quality Of Service Manual page 438

Shared Queue QoS Commands
Parameters
percent — The percent of buffers from the total buffer pool space for the maximum amount of
rate
Syntax rate [percent] [cir percent]
no rate
Context config>qos>shared-queue>queue
Description
This command defines the administrative Peak Information Rate (PIR) and the administrative Com-
mitted Information Rate (CIR) parameters for the queue. The PIR defines the percentage that the
queue can transmit packets (for SAP ingress queues) or out an egress interface (for SAP egress
queues). Defining a PIR does not necessarily guarantee that the queue can transmit at the intended
rate. The actual rate sustained by the queue can be limited by oversubscription factors or available
egress bandwidth.
The CIR defines the percentage at which the system prioritizes the queue over other queues compet-
ing for the same bandwidth. For SAP ingress, the CIR also defines the rate that packets are considered
in-profile by the system. In-profile packets are preferentially queued by the system at egress and at
subsequent next hop nodes where the packet can traverse. To be properly handled as in- or out-of-pro-
file throughout the network, the packets must be marked accordingly for profiling at each hop.
The CIR can be used by the queue's parent commands cir-level and cir-weight parameters to define
the amount of bandwidth considered to be committed for the child queue during bandwidth allocation
by the parent scheduler.
The rate command can be executed at anytime, altering the PIR and CIR rates for all queues created
through the association of the SAP ingress or SAP egress QoS policy with the queue-id.
Parameters percent — Defines the percentage of the max rate allowed for the queue. When the rate command is
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Forwarding Class
Network-Control
High-1
Expedited
High-2
Low-1
Assured
Low-2
Best-Effort
buffers, expressed as a decimal integer. If 10 MB is the total buffers in the buffer pool, a value of
10 would limit the maximum queue size to 1MB (10%) of buffer space for the forwarding class
queue. If the total size is increased to 20MB, the existing value of 10 would automatically
increase the maximum size of the queue to 2MB.
Values
0 — 100
executed, a valid PIR setting must be explicitly defined. When the rate command has not been
Fowarding Class Label
nc
h1
ef
h2
l1
af
l2
be
7950 XRS Quality of Service Guide
Default MBS
25
25
50
50
25
50
50
50