Queue Sharing and Redirection
Quality of Service Guide 457
The packet-byte-offset command is meant to be an arbitrary mechanism that can be used to either add
downstream frame encapsulation or remove portions of packet headers.
When a packet-byte-offset value is applied to a queue instance, it adjusts the immediate packet size.
This means that the queue rates (i.e., operational PIR and CIR) and queue bucket updates use the
adjusted packet size. In addition, the queue statistics will also reflect the adjusted packet size.
Scheduler policy rates, which are data rates, will use the adjusted packet size.
The port scheduler max-rate and the priority level rates and weights, if a Weighted Scheduler Group
is used, are always on-the-wire rates and thus use the actual frame size. The same goes for the agg-rate-
limit on a SAP, a subscriber, or a Multi-Service Site (MSS) when the queue is port-parented.
When the user enables frame-based-accounting in a scheduler policy or queue-frame-based-
accounting with agg-rate-limit in a port scheduler policy, the queue rate will be capped to a user
configured on-the-wire rate, but the packet-byte-offset value is still in effect as explained above. This
command is ignored on FP1 hardware.
The no version of this command is used to remove per packet size modifications from the queue.
Parameters add bytes — The add keyword is mutually exclusive to the subtract keyword. Either add or
subtract must be specified. When add is defined, the corresponding bytes parameter
specifies the number of bytes that is added to the size of each packet associated with the queue
for scheduling and accounting purposes.
Values 0 to 32
subtract bytes — The subtract keyword is mutually exclusive to the add keyword. Either add or
subtract must be specified. When subtract is defined, the corresponding bytes parameter
specifies the number of bytes that is subtracted to the size of each packet associated with the
queue for scheduling and accounting purposes. The minimum resulting packet size used by
the system is 1 byte.
Values 0 to 64
wred-queue
Syntax wred-queue [policy slope-policy-name] [mode {native | pool-per-queue}] [slope-usage
{default | exceed-low}]
no wred-queue
Context config>qos>qgrps>egr>qgrp>queue
Description This command allows the configuration of WRED per queue with the following options:
• Native hardware WRED
This uses the hardware per queue WRED capabilities of the FP3 and is configured with the
native keyword.
• Pool per queue WRED
To Next Page
Loading...
