Comparison and Evaluation of Design Choices for Implementing the Virtual Interface Architecture (VIA)

The Virtual Interface Architecture (VIA) specification has been developed to standardize user-level network interfaces that provide low latency, high bandwidth communications. Few hardware and software implementations of VIA exist. Since the VIA specification is flexible, different choices exist for implementing various components of VIA such as doorbells, address translation methods, and completion queues. Although previous studies have evaluated the overall performance of different VIA implementations, there has not been a comparative study on the performance of VIA components. In this paper, we evaluate and compare the performance of different implementations of essential VIA components. We discuss the pros and cons of each design approach and describe the required support for implementing each of them. As a user application, we use the NAS Parallel Benchmarks to study the effect of caching the address translation tables on the NIC and to study completion queues. As a hardware platform we use the IBM Netfinity SP cluster running the NT 4.0 operating system and a Myrinet connected cluster of PCs running the Linux operating system.