Configuring Queue Scheduling - Huawei Quidway S3500 Series Operation Manual

Operation Manual - QoS/ACL
Quidway S3500 Series Ethernet Switches
You should note that the packets redirected to CPU cannot be forwarded any longer.
Note:
The redirection configuration is valid only when the action taken by ACLs is permit.
For more information about the traffic-redirect command, see Command Manual.

2.4.6 Configuring Queue Scheduling

Each port on a switch supports eight output queues. The system put packets into the
output queues at a port based on packets' local-precedence. To prevent resource
contention of packets at the time of network congestion, queue scheduling mechanism
is adopted. So far, Strict Priority (SP) and Weighted Round Robin (WRR) WRR
scheduling algorithms are supported.
Different queue scheduling algorithms may apply on different queues at each port.
Three queue scheduling approaches are supported:
1) Apply SP scheduling on all the queues;
2) Apply WRR scheduling on all the queues. In this approach, output queues are
assigned into WRR group 1 and WRR group 2. In the WRR scheduling approach,
all the queues are assigned into WRR group 1 by default.
3) Combine SP and WRR by applying them on different queues at the same time. In
this approach, the groups are scheduled by priority strictly, and then the
scheduling is performed in each group by scheduling algorithms: Strict scheduling
is applied inside the SP scheduling group while polling is applied inside the WRR
scheduling group.
Note:
You must follow these rules to group eight outgoing queues at a port:
The queues in one group must have consecutive queue numbers. For example,
queue 3, 4 and 5 have consecutive queue numbers and thus can be grouped in one
queue scheduling group; whereas queue 3, 4 and 7 cannot be grouped in one
group.
You must group the queues with high priority in the SP group, the queues with
comparatively lower priority in the WRR1 group, and the queues with the lowest
priority in the WRR2 group. Ensure that the priorities of all the queues in SP are
higher than that of all the queues in WRR1, and the priorities of all the queues in
WRR1 are higher than that of all the queues in WRR2.
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Chapter 2 QoS Configuration