Approaches to improving performance of STREAMS-based protocol stacks

STREAMS kernel mechanisms are being used to implement networking protocols in a number of operating systems, like UNIX, Windows, and pSOS. STREAMS provides a number of desirable features for modular protocol stack implementation by defining a high degree of standardization for implementing protocol layer modules and for message transfer between the modules. But this strict layered and modular approach prevents flexibility in implementing techniques that can result in high performance. The original STREAMS-based stacks have shown very poor protocol performance. A number of improved techniques for implementing STREAMS-based protocol stacks have been suggested in the literature in the past few years. These techniques have resulted in high-performance STREAMS-based stacks that match the performance of BSD UNIX-based stacks. This article makes a study of these new approaches and discusses the performance gains achieved by them. These approaches can be used for implementing high-performance protocol stacks in the STREAMS kernel, over both uniprocessor and multiprocessor systems.