Aggregate Rate Limits For Directly Attached Queues - Alcatel-Lucent 7950 Quality Of Service Manual

Aggregate Rate Limits for Directly Attached Queues

When all queues for a SAP, multi-service site
(using the port-parent command), it is possible to configure an agg-rate-limit for the queues. This
is beneficial since the port scheduler does not provide a mechanism to enforce an aggregate SLA
for a service
the port scheduler when it is desirable to manage the congestion at the egress port based on class
priority instead of on a per service object basis.
The agg-rate-limit is not supported when one or more queues on the object are attached to an
intermediate service scheduler. In this event, it is expected that the intermediate scheduler
hierarchy will be used to enforce the aggregate SLA. Attaching an agg-rate-limit is mutually
exclusive to attaching an egress scheduler policy at the SAP
effect, a scheduler policy cannot be assigned. Once a scheduler policy is assigned on the egress
side of a SAP
Since the sap-egress policy defines a queue's parent association before the policy is associated
with a service SAP
define an intermediate scheduler parenting that does not exist. As stated above, queues in this state
are considered to be orphaned and automatically attached to port scheduler priority 1. Orphaned
queues are included in the aggregate rate limiting behavior on the SAP
within.
SAP Egress QoS Policy Queue Parenting
A sap-egress QoS policy queue may be associated with either a port parent or an intermediate
scheduler parent. The validity parent definition cannot be checked at the time it is provisioned
since the application of the QoS policy is not known until it is applied to an egress SAP
allowed to have port or intermediate parenting decided on a queue by queue basis, some queues
tied directly to the port scheduler priorities while other queues are attached to intermediate
schedulers.
Network Queue QoS Policy Queue Parenting
A network-queue policy only supports direct port parent priority association. Intermediate
schedulers are not supported on network ports.
7950 XRS Quality of Service Guide
and the agg-rate-limit provides this ability. Queues may be provisioned directly on
or
, an agg-rate-limit cannot be assigned.
or
, it is possible for the policy to either not define a port-parent association or
or
QoS Scheduler Policies
instance are attached directly to the port scheduler
or
. Once an aggregate rate limit is in
or
instance they are created
or
. It is
or
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