Hierarchical scheduling system with layer bypass including updating scheduling information of a scheduling layer for each item whether or not it bypasses the scheduling layer

Abstract

In one embodiment, a hierarchical scheduling system including multiple scheduling layers with layer bypass is used to schedule items (e.g., corresponding to packets). This scheduling of items performed in one embodiment includes: propagating first items through the hierarchical scheduling system and updating scheduling information in each of the plurality of scheduling layers based on said propagated first items as said propagated first items propagate through the plurality of scheduling layers, and bypassing one or more scheduling layers of the plurality of scheduling layers for scheduling bypassing items and updating scheduling information in each of said bypassed one or more scheduling layers based on said bypassing items. In one embodiment, this method is performed by a particular machine. In one embodiment, the operations of propagating first items through the hierarchical scheduling system and bypassing one or more scheduling layers are done in parallel.