In one embodiment of a network device, multiple packet sources contend for access to a packet processing pipeline. The packet processing pipeline tracks the usage of lookup resources by each of the multiple packet sources. When a packet source is detected to be using more than an acceptable allocation of the lookup resources, access to the packet processing pipeline for that source is limited or curtailed to bring that source back within an acceptable allocation of resources. This backpressure mechanism can be used to control sources that, although within a bandwidth limit, are submitting a packet type mix that is consuming unfair percentages of lookup resources in an oversubscribed system. Other embodiments are described and claimed.