DES-3226S Layer 2 Fast Ethernet Switch User’s Guide
QOS Commands
145
config scheduling
Purpose
Used to configure the traffic scheduling
mechanism for each COS queue.
Syntax
config scheduling <class_id> [max_packet
<value>/max_latency <value>]
Description
The switch contains 4 hardware priority
queues. Incoming packets must be mapped to
one of these four queues. This command is
used to specify the rotation by which these four
hardware priority queues are emptied.
The switch’s default (if the
config scheduling
command is not used, or if the
config
scheduling
command is entered with both
max_packet
and
max_latency
parameters
are set to
0
) is to empty the 4 hardware
priority queues in order
−
from the highest
priority queue (hardware queue 3) to the
lowest priority queue (hardware queue 0).
Each hardware queue will transmit all of the
packets in its buffer before allowing the next
lower priority queue to transmit its packets.
When the lowest hardware priority queue has
finished transmitting all of its packets, the
highest hardware priority queue can again
transmit any packets it may have received.
The
max_packets
parameter allows you to
specify the maximum number of packets a
given hardware priority queue can transmit
before allowing the next lowest hardware
priority queue to begin transmitting its