Abstract: A packet processor or packet processing pipeline may implement programmatic selection of load balancing output for forwarding paths. Programmatic selection for load balancing among forwarding paths may be enabled or disabled at one or more stages. If programmatic selection is enabled when network packets are received, a programmatically identified path may be provided as the selected path of a load balancing scheme at a stage. Forwarding of the packet may then be performed according to the selected path.

Abstract: Techniques are disclosed regarding interfaces, each configured to output network packets. The techniques can include a memory storing a first multipath group associated with the interfaces and a routing table, containing a first route to the first multipath group. The techniques can also include congestion detection logic configured to determine that an interface of the first multipath group is congested. The techniques can additionally include congestion avoidance logic configured to, upon determining that the interface of the first multipath group is congested, generate a second route in the routing table to a second multipath group associated with the interfaces of the first multipath group, wherein the second route diverts a flow of network packets from the first multipath group to the second multipath group.

Abstract: Techniques are provided for allocating hardware resources for an equal-cost multi-path (ECMP) group based on information about the network architecture. A table in memory may include a plurality of entries. Each entry may include interface set and a number of interfaces. Each interface set may represent a list of interfaces for the network device for a given network connection. The network device may receive a list of interfaces for allocating resource for an EMCP group. The network device may select an entry from the table by identifying an interface set that includes all of the interfaces for the ECMP group. The network device may determine a size of the ECMP group using a number of interfaces for the identified interface set from the entry from the table and allocate hardware resources (e.g., memory) for the ECMP group based on the determined size of the ECMP group.

Abstract: Techniques are disclosed regarding interfaces, each configured to output network packets. The techniques can include a memory storing a first multipath group associated with the interfaces and a routing table, containing a first route to the first multipath group. The techniques can also include congestion detection logic configured to determine that an interface of the first multipath group is congested. The techniques can additionally include congestion avoidance logic configured to, upon determining that the interface of the first multipath group is congested, generate a second route in the routing table to a second multipath group associated with the interfaces of the first multipath group, wherein the second route diverts a flow of network packets from the first multipath group to the second multipath group.

Abstract: A packet processor or packet processing pipeline may implement forwarding table updates during live packet stream processing. Updates may be updates to add or remove entries from group of entries in a forwarding table or may be updates to defragment the available entries in a chain of entries maintained in a forwarding table. Reserved entries may be allocated for moving entries as part of updates so that migrations of the entries from one location to another may be performed atomically.