Foster Parent Behavior For Orphaned Queues And Schedulers - Alcatel-Lucent 7950 Quality Of Service Manual

Egress Port-Based Schedulers

Foster Parent Behavior for Orphaned Queues and Schedulers

All queues and schedulers on a port that has a port-based scheduler policy configured will be
subject to bandwidth allocation through the port-based schedulers. All queues and schedulers that
are not configured with a scheduler parent are considered to be orphaned when port-based
scheduling is in effect. This includes access and network queue schedulers at the SAP, multi-
service site, and port level.
By default, orphaned queues and schedulers are allocated bandwidth after all queues and
schedulers in the parented hierarchy have had bandwidth allocated "within-cir" and "above-cir".
In essence, an orphaned scheduler or queue can be considered as being foster parented by the port
scheduler. Orphaned queues and schedulers have an inherent port scheduler association as shown
below:
•
•
•
•
The above-CIR weight = 0 value is only used for orphaned queues and schedulers on port
scheduler enabled egress ports. The system interprets weight=0 as priority level 0 and will only
distribute bandwidth to level 0 once all other properly parented queues and schedulers have
received bandwidth. Orphaned queues and schedulers all have equal priority to the remaining port
bandwidth.
The default orphan behavior can be overridden for each port scheduler policy by using the orphan
override command. The orphan override command accepts the same parameters as the port parent
command. When the orphan override command is executed, all orphan queues and schedulers are
treated in a similar fashion as other properly parented queues and schedulers based on the override
parenting parameters.
It is expected that an orphan condition is not the desired state for a queue or scheduler and is the
result of a temporary configuration change or configuration error.
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Within-CIR priority = 1
Within-CIR weight = 0
Above-CIR priority = 1
Above-CIR weight = 0
7950 XRS Quality of Service Guide