Non-blocking shared state in an intrusion-prevention system

A system includes a plurality of deep packet inspection engines for performing deep packet inspection on packets in a network. The deep packet inspection engines share at least some state. One of the deep packet inspection engines is assigned responsibility for writing data to the shared state. For one of the deep packet inspection engines to write data to the shared state, the deep packet inspection write provides a write request to the assigned writer deep packet inspection engine, which queues the request on a write queue. The writer deep packet inspection engine may queue multiple write requests from multiple deep packet inspection engines. The writer deep packet inspection engine dequeues the write requests and processes them serially, thereby avoiding the need to manage contention using locks.