Eager Data Transfer Mechanism for Reducing Communication Latency in User-Level Network Protocols

TitleEager Data Transfer Mechanism for Reducing Communication Latency in User-Level Network Protocols
Publication TypeJournal Article
Year of Publication2008
AuthorsWon, C. - H., B. Lee, K. Park, and M. - J. Kim
JournalJournal of Information Processing Systems
Volume4
Issue4
Pagination133 - 144
Date Published12/2008
ISSN1976-913X
Abstract

Clusters have become a popular alternative for building high-performance parallel computing systems. Today's high-performance system area network (SAN) protocols such as VIA and IBA significantly reduce user-to-user communication latency by implementing protocol stacks outside of operating system kernel. However, emerging parallel applications require a significant improvement in communication latency. Since the time required for transferring data between host memory and network interface (NI) make up a large portion of overall communication latency, the reduction of data transfer time is crucial for achieving low-latency communication. In this paper, Eager Data Transfer (EDT) mechanism is proposed to reduce the time for data transfers between the host and network interface. The EDT employs cache coherence interface hardware to directly transfer data between the host and NI. An EDT-based network interface was modeled and simulated on the Linux-based, complete system simulation environment, Linux/SimOS. Our simulation results show that the EDT approach significantly reduces the data transfer time compared to DMA-based approaches. The EDTbased NI attains 17% to 38% reduction in user-to-user message time compared to the cache-coherent DMA-based NIs for a range of message sizes (64 bytes ~ 4 Kbytes) in a SAN environment.

DOI10.3745/JIPS.2008.4.4.133
Short TitleJournal of Information Processing Systems