Configuring An Sp Queue; Configuration Procedure - H3C S5120-EI Series Operation Manual

The allocable bandwidth (allocable bandwidth = the total bandwidth – the sum of the minimum
guaranteed bandwidth for each queue) is divided and allocated to each queue based on queue
precedence.
For example, assume that the total bandwidth of an interface is 10 Mbps and there are five flows on the
interface, with the precedence being 0, 1, 2, 3, and 4 respectively and the minimum guaranteed
bandwidth being 128 kbps, 128 kbps, 128 kbps, 64 kbps, and 64 kbps respectively. Then,
The allocable bandwidth = 10 Mbps – (128 + 128 + 128 + 64 + 64) kbps = 9.5 Mbps
The total allocable bandwidth quota is the sum of all the (precedence value + 1)s, that is, 1 + 2 + 3
+ 4 + 5 = 15.
The bandwidth percentage assigned to each flow is (precedence value of the flow + 1)/total
allocable bandwidth quota. The bandwidth percentages for flows are 1/15, 2/15, 3/15, 4/15, and
5/15 respectively.
The bandwidth allocated to a queue = Minimum guaranteed bandwidth + bandwidth allocated to
the queue from the allocable bandwidth
Because WFQ can balance the delay and jitter of every flow when congestion occurs, it is effectively
applied in some special occasions. For example, WFQ is adopted in the assured forwarding (AF)
services of the Resource Reservation Protocol (RSVP). In Generic Traffic Shaping (GTS), WFQ is used
to schedule buffered packets.
4) SP+WRR queue scheduling algorithm
You can implement SP+WRR queue scheduling on a port by assigning some queues on the port to the
SP scheduling group and the others to the WRR scheduling group (that is, group 1). Packets in the SP
scheduling group are scheduled preferentially. When the SP scheduling group is empty, packets in the
WRR scheduling group are scheduled. Queues in the SP scheduling group are scheduled by SP.
Queues in the WRR scheduling group are scheduled by WRR.

Configuring an SP Queue

By default, WRR queue scheduling algorithm is adopted on all the ports. You can adopt SP queue
scheduling algorithm instead as required.

Configuration Procedure

Follow these steps to configure SP queues:
To do...
Enter system view
Enter port
Enter
view
port view
or port
Enter port
group
group
view
view
Configure SP queue
scheduling algorithm
Use the command...
system-view
interface interface-type
interface-number
port-group manual
port-group-name
qos sp
5-4
Remarks
—
Perform either of the two operations.
The configuration performed in Ethernet
interface view applies to the current port
only. The configuration performed in port
group view applies to all the ports in the
port group.
Required
By default, all the ports adopt the WRR
queue scheduling algorithm, with the
weight values assigned to queue 0 through
queue 7 being 1, 2, 3, 4, 5, 9, 13, and 15.