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Hierarchy Level


Adjust the maximum size of the shared-buffer pool at the egress buffer partition for each queue.

During congestion or micro-burst scenarios, dedicated buffers can be exhausted, and queues start consuming from the shared buffer pool. The switch dynamically calculates the limit of buffers that each queue can consume from the shared buffer pool based on the dynamic threshold setting called alpha. The purpose of alpha, or buffer-dynamic-threshold, is to scale the current free resources to determine an instantaneous threshold.


You adjust the maximum size of the global shared-buffer pool by configuring the dynamic-threshold value at the [edit class-of-service shared-buffer egress buffer-partition] hierarchy level.

When you configure the buffer dynamic threshold at both the global and the scheduler (per-queue) level, the per-queue value takes precedence.


buffer-dynamic-threshold value

Threshold for maximum buffer share for a queue at the egress buffer partition.

Range: 0-10

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 22.3R1 for QFX5220 devices.