buffer-rate (Schedulers)
Syntax
buffer-rate (percent percent | rate);
Hierarchy Level
[edit class-of-service schedulers scheduler-name]
Description
Configure the base rate for buffer size calculation. The buffer rate is the target rate of a VOQ, which is the intended egress queue rate during typical congestion. The target rate is an import parameter for VOQs, as the ratio of the drain rate to the target rate determines how much buffer adjustment happens at ingress.
The VOQ target rate is equal to the lesser of the buffer rate and the calculated shaping rate. If you don't define the buffer rate, then the VOQ target rate is equal to the scheduler transmit rate. If you also don't define the scheduler transmit rate, then the VOQ target rate is equal to the calculated shaping rate.
For platforms that support VOQs each ingress Packet Forwarding Engine (PFE) provides up to eight virtual output queues for a single egress port. The egress PFE distributes the bandwidth to each ingress virtual output queue; therefore they receive equal treatment regardless of their presented load. The drain rate of a queue is the rate at which a queue is draining. The egress Packet Forwarding Engine divides its bandwidth for each output queue equally across the ingress PFEs. So, the drain rate of each ingress PFE = drain rate of the output queue/number of ingress PFEs.
Options
percent percentage |
Buffer rate as a percentage of the total buffer.
|
rate |
Buffer rate as an absolute value. |
Required Privilege Level
interface—To view this statement in the configuration.
interface-control—To add this statement to the configuration.
Release Information
Statement introduced in Junos OS Evolved Release 24.4R1.