Exploiting NIC architectural support for enhancing IP-based protocols on high-performance networks

摘要

While a number of user-level protocols have been developed to reduce the gap between the performance capabilities of the physical network and the performance actually available, their compatibility issues with the existing sockets-based applications and IP-based infrastructure has been an area of major concern. To address these compatibility issues while maintaining a high performance, a number of researchers have been looking at alternative approaches to optimize the existing traditional protocol stacks. Broadly, previous research has broken up the overheads in the traditional protocol stack into four related aspects, namely: (ⅰ) compute requirements and contention, (ⅱ) memory contention, (ⅲ) I/O bus contention and (ⅳ) system resources' idle time. While previous research dealing with some of these aspects exists, to the best of our knowledge, there is no work which deals with all these issues in an integrated manner while maintaining backward compatibility with existing applications and infrastructure. In this paper, we address each of these issues, propose solutions for minimizing these overheads by exploiting the emerging architectural features provided by modern Network Interface Cards (NICs) and demonstrate the capabilities of these solutions using an implementation based on UDP/IP over Myrinet. Our experimental results show that with our implementation of UDP, termed as E-UDP, can achieve up to 94% of the theoretical maximum bandwidth. We also present a mathematical performance model which allows us to study the scalability of our approach for different system architectures and network speeds.