Ethernet IQ2 PIC Schedulers

By default, each Ethernet IQ2 PIC is allocated a fixed number of the 1024 available schedulers for each port during PIC initialization. For example, the 8-port Gigabit Ethernet IQ2 PIC is allocated 128 schedulers for each port. This number cannot be changed after the PIC is operational and can limit the utilization of shapers among the ports. Each of the 1024 schedulers is mapped at the logical interface (unit) level, and each scheduler can support up to eight forwarding classes.

Three schedulers are reserved on each port. One is for control traffic, one is for port-level shaping, and the last is for unshaped logical interface traffic. These are allocated internally and automatically.

When you configure schedulers for a port on an Ethernet IQ2 PIC:

• The three reserved schedulers are added to the configured value.
• The configured value is adjusted upward to the nearest multiple of 4 (schedulers are allocated in multiples of 4).
• After all configured schedulers are allocated, any remaining unallocated schedulers are partitioned equally across the other ports.
• Any remaining schedulers that cannot be allocated meaningfully across the ports are allocated to the last port.

If the configured scheduler number is changed, the Ethernet IQ2 PIC will be restarted when the configuration is committed.

Note: If you deactivate and reactivate a port configured with a non-default number of schedulers then the whole Ethernet IQ2 PIC will restart.

To configure the number of schedulers assigned to a port on an Ethernet IQ2 PIC, include the schedulers statement for the Ethernet IQ2 PIC interface at the [edit interfaces interface-name] hierarchy level:

You can configure between 1 and 1024 schedulers on a port.

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