Alcatel-Lucent 7450 Quality Of Service Manual page 459

As packets attempt to enter the egress queue, they are associated with the high, low, or exceed WRED
slope based on the packets' profile. If the packet is in-profile, the high slope is used. If the packet is
out-of-profile, the low slope is used, and, if the packet is exceed-profile, then exceed slope is used. This
mapping of packet profile to slope is enabled using the slope-usage default parameter. Each WRED
slope performs a probability discard based on the current weighted average pool depth.
When wred-queue is enabled for an egress queue group queue on FP2 or higher based hardware, the
queue pool hi-low-prio-only and hi-prio-only commands are ignored; traffic mapped to a slope which
is shutdown will use the MBS drop tail.
The configuration of wred-queue mode pool-per-queue is ignored on FP1 hardware. The resource
usage for the wred-queue pool-per-queue per forwarding plane can be seen in the tools dump
resource-usage card [slot-num] fp [fp-number] output under Dynamic Q2 Wred Pools.
The no form of the command restores the generic buffer pool behavior to the queue. The WRED pool
is removed from the system. The queue will be moved to either the default buffer pool or to a named
pool if defined and the pool exists. The queue then uses the default congestion control behavior.
Default no wred-queue
Parameters
slope-policy-name — Specifies an existing slope policy that is used to override the default WRED
mode {native | pool-per-queue} — The mode species whether the WRED per queue is using the
slope-usage {default | exceed-low} — This parameter specifies congestion control to be used.
queue
Syntax queue queue-id
no queue
Quality of Service Guide
slope policy.
native FP3 WRED capabilities or the FP2 and later hardware pool per queue.
Values native - use the hardware per queue WRED capabilities of the FP3
and requires slope-usage exceed-low.
pool-per-queue - each queue uses its own pool and the WRED
capabilities of the pool to provide WRED per queue. This is
supported on both FP2 and later hardware and requires slope-
usage default.
Default native
Values default - maps the in, out, and exceed profile traffic to the high,
low, and exceed WRED slopes respectively; this is only supported
for pool-per-queue mode.
exceed-low - maps the out and exceed profile traffic to the low
and exceed WRED slopes with the in profile traffic using the
MBS drop tail. This is only supported for native mode.
Default exceed-low
Queue Sharing and Redirection
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