Alcatel-Lucent 7950 Quality Of Service Manual page 505

child with a cir-weight equal to 0 is skipped in this pass.) Each child may consume bandwidth up to the
child's frame based within-cir offered load. The remaining available port bandwidth is then offered to the
next lower priority level until level 1 is reached.
The second pass is called the above-cir pass and consists of providing the remaining available port
bandwidth to each of the eight priority levels a second time. Again, each level takes the offered load and
distributes it to all child members that have a port-parent level equal to the current priority level. Each child
may consume bandwidth up to the remainder of the child's frame based offered load (some of the offered
load may have been serviced during the within-cir pass). The remaining available port bandwidth is then
offered to the next priority level until level 1 is again reached.
If the port scheduling policy is using the default orphan behavior (orphan-override has not been configured
on the policy), the system then takes any remaining port bandwidth and allocates it to the orphan queues and
scheduler on priority level 1. In a non-override orphan state, all orphans are attached to priority level 1 using
a weight of 0. The 0 weight value causes the system to allocate bandwidth equally to all orphans based on
each orphan queue or scheduler's ability to use the bandwidth. If the policy has an orphan-override
configured, the orphans are handled based on the override commands parameters in a similar fashion to
properly parented queues and schedulers.
The port scheduler priority level command rate keyword is used to optionally limit the total amount of
bandwidth that is allocated to a priority level (total for the within-cir and above-cir passes). The cir keyword
optionally limits the first pass bandwidth allocated to the priority level during the within-cir pass.
When executing the level command, at least one of the optional keywords, rate or cir, must be specified. If
neither keyword is included, the command will fail.
If a previous explicit value for rate or cir exists when the level command is executed, and either rate or cir is
omitted, the previous value for the parameter is overwritten by the default value and the previous value is
lost.
The configured priority level rate limits may be overridden at the egress port or channel using the egress-
scheduler-override level priority-level command. When a scheduler instance has an override defined for a
priority level, both the rate and cir values are overridden even when one of them is not explicitly expressed
in the override command. For instance, if the cir kilobits-per-second portion of the override is not expressed,
the scheduler instance defaults to not having a CIR rate limit for the priority level even when the port
scheduler policy has an explicit CIR limit defined.
Default
no level priority-level
Parameters
priority-level — Specifies to which priority level the level command pertains. Each of the eight levels is
represented by an integer value of 1 to 8, with 8 being the highest priority level.
Values
rate pir — Specifies the total bandwidth limits allocated to priority-level.
Values
cir cir — The cir specified limits the total bandwidth allocated in the within-cir distribution pass to priority-
level. When cir is not specified, all the available port or channel bandwidth may be allocated to the
specified priority level during the within-cir pass.
Values
7950 XRS Quality of Service Guide
1 — 8 (8 is the highest priority)
1 — 40000000 (Kilobits per second (1,000 bits per second))
1 — 40000000 (Kilobits per second (1,000 bits per second))
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