xStack DGS-3612G Layer 3 Gigabit Ethernet Managed Switch CLI Manual
DGS-3612G:4#show bandwidth_control 1-10
Command: show bandwidth_control 1-10
Bandwidth Control Table
Port RX Rate (64Kbit/sec) TX_Rate (64Kbit/sec)
---- ------------------------ ----------------------
1 no_limit 10
2 no_limit 10
3 no_limit 10
4 no_limit 10
5 no_limit 10
6 no_limit 10
7 no_limit 10
8 no_limit 10
9 no_limit 10
10 no_limit 10
DGS-3612G:4#
config scheduling
Purpose
Used to configure the traffic scheduling mechanism for each COS queue.
Syntax
config scheduling <class_id 0-6> {max_packet <value 0-15>}
Description
The Switch contains seven hardware priority queues. Incoming packets must
be mapped to one of these seven queues. This command is used to specify
the rotation by which these eight 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 the
max_packet
set to 0) is to
empty the hardware priority queues in order
−
from the highest priority queue
(hardware queue 6) 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 users 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 packets. A value
between 0 and 15 can be specified. For example, if a value of 3 is specified,
then the highest hardware priority queue (queue 6) will be allowed to transmit
three packets
−
then the next lowest hardware priority queue (number 5) will
be allowed to transmit three packets, and so on, until all of the queues have
transmitted three packets. The process will then repeat.
Entering a
0
into the
<value 0-15>
field of the
max_packet
parameter allows
for the creation of a
Combination Queue
for the forwarding of packets. This
Combination Queue
allows for a combination of strict and weight-fair
(weighted round-robin
“
WRR
”
) scheduling. Priority classes that have a
0
in
the
max_packet
field will forward packets with strict priority scheduling. The
remaining classes, that do not have a
0
in their
max_packet
field, will follow a
weighted round-robin (
WRR
) method of forwarding packets — as long as the
priority classes with a
0
in their
max_packet
field are empty. When a packet
arrives in a priority class with a
0
in its
max_packet
field, this class will
automatically begin forwarding packets until it is empty. Once a priority class
with a
0
in its
max_packet
field is empty, the remaining priority classes will
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