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Queue mode – LevelOne GTL-2691 User Manual

Page 1157

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| Class of Service Commands

Priority Commands (Layer 2)

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show queue cos-map (1160)

queue mode

This command sets the scheduling mode used for processing each of the

class of service (CoS) priority queues. The options include strict priority,

Weighted Round-Robin (WRR), or a combination of strict and weighted

queuing. Use the no form to restore the default value.

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YNTAX

queue mode {strict | wrr | strict-wrr [queue-type-list]}
no queue mode

strict - Services the egress queues in sequential order, transmitting

all traffic in the higher priority queues before servicing lower priority

queues. This ensures that the highest priority packets are always

serviced first, ahead of all other traffic.
wrr - Weighted Round-Robin shares bandwidth at the egress ports

by using scheduling weights (based on the

queue weight

command), and servicing each queue in a round-robin fashion.
strict-wrr - Strict priority is used for the high-priority queues and

Weighted Round-Robin for the rest of the queues.
queue-type-list - Indicates if the queue is a normal or strict type.

(Options: 0 indicates a normal queue, 1 indicates a strict queue)

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WRR

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Interface Configuration (Ethernet, Port Channel)

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SAGE

The switch can be set to service the port queues based on strict

priority, WRR, or a combination of strict and weighted queueing.

Strict priority requires all traffic in a higher priority queue to be

processed before lower priority queues are serviced.

Weighted Round-Robin (WRR) uses a predefined relative weight for

each queue that determines the percentage of service time the switch

services each queue before moving on to the next queue. This prevents

the head-of-line blocking that can occur with strict priority queuing. Use

the

queue weight

command to assign weights for WRR queuing to the

eight priority queues.

If Strict and WRR mode is selected, a combination of strict service is

used for the high priority queues and weighted service for the

remaining queues. The queues assigned to use strict priority should be

specified using the Strict Mode field parameter.