Edge-Core ECS4510-28P User Manual page 271

C U
OMMAND SAGE
◆ Strict priority requires all traffic in a higher priority queue to be
processed before lower priority queues are serviced.
WRR queuing specifies a relative weight for each queue. 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.
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.
A weight can be assigned to each of the weighted queues (and thereby
◆
to the corresponding traffic priorities). This weight sets the frequency
at which each queue is polled for service, and subsequently affects the
response time for software applications assigned a specific priority
value.
Service time is shared at the egress ports by defining scheduling
weights for WRR, or one of the queuing modes that use a combination
of strict and weighted queuing.
◆ The specified queue mode applies to all interfaces.
Protocols used to synchronize distributed switches use packets of 1588
◆
bytes to control the synchronization process. This switch therefore
assigns packets of this size to the highest priority queue to ensure
quick passage.
P
ARAMETERS
These parameters are displayed:
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, and servicing each queue in a
round-robin fashion. (This is the default setting.)
Strict and WRR – Uses strict priority on the high-priority queues
■
and WRR on the remaining queues.
Queue ID – The ID of the priority queue. (Range: 0-7)
◆
Strict Mode – If "Strict and WRR" mode is selected, then a
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combination of strict service is used for the high priority queues and
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| Class of Service
C 10
HAPTER
Layer 2 Queue Settings