Abstract: A network device organizes packets into various queues, in which the packets await processing. Queue management logic tracks how long certain packet(s), such as a designated marker packet, remain in a queue. Based thereon, the logic produces a measure of delay for the queue, referred to herein as the “queue delay.” Based on a comparison of the current queue delay to one or more thresholds, various associated delay-based actions may be performed, such as tagging and/or dropping packets departing from the queue, or preventing addition enqueues to the queue. In an embodiment, a queue may be expired based on the queue delay, and all packets dropped. In other embodiments, when a packet is dropped prior to enqueue into an assigned queue, copies of some or all of the packets already within the queue at the time the packet was dropped may be forwarded to a visibility component for analysis.

Abstract: Techniques for more optimally balancing operations across a set of buffers, such as in buffering packets in a network device or in other contexts, are disclosed. The techniques make use of an ordered list of buffers from which the next available buffer is selected for each operation, as needed. The buffers are first prioritized based on the state(s) of the relevant buffers and/or other factors. The resulting ordered list is then processed using re-ordering logic. This re-ordering logic may, for example, randomly or pseudo-randomly trade the positions of various sets of buffers within the prioritized list. Among other effects, the re-ordering logic thus reduces buffer skew problems from delayed propagation of buffer state information and other issues. In an embodiment, the re-ordering logic is divided into multiple levels of processing, with each level separately passing through the list. Each level of processing may utilize differently configured re-ordering logic.