nanoProtean: scalable system software for a gigabit active router
D. Craig, Hwangnam Kim, R. Sivakumar, Vaduvur Bharghavan, Constantine D. Polychronopoulos · 2002
We introduce nanoProtean, a new router operating system and execution environment that reduces system overhead, making it possible to process the packets produced by gigabit networks. The ovearhead decreases as the offered load per packet increases due to the following features in nanoProtean (i) a completely preemptable operating system, (ii) efficient management of the system's job queue, and (iii) system support for fine-grain sharing of processing time amongst packets. These features are a result of a novel integration of efficient thread scheduling for multiprocessors and interrupt handling. Experimental analysis used to test our systems scalability uses a technique to emulate processing requests generated in real-time at 802.3z (gigabit) line speeds and greater. Our results demonstrate 2 Gbps routing; with MAE-East tables on two processors, and system overheads decreasing from 3.6 /spl mu/s per packet to 1.64 /spl mu/s per packet on one processor. By reducing the system overhead, we also demonstrate that nanoProtean enables active networking in a router supporting gigabit connections.