Minimizing protocol processing in multimedia servers - implementation and evaluation of network level framing

P. Halvorsen1, T. Plagemann1, V. Goebel1
1Department of Informatics, University of Oslo, Oslo, Norway

Tóm tắt

Data servers for multimedia applications like news-on-demand represent a severe bottleneck, because a potentially very high number of users concurrently retrieve data with high data rates. In the Intermediate Storage Node Concept (INSTANCE) project, we develop a new architecture for media-on-demand servers that maximizes the number of concurrent clients a single server can support. Traditional bottlenecks, like copy operations, multiple copies of the same data element in main memory, and checksum calculation in communication protocols are avoided by applying three orthogonal techniques: network level framing (NLF), zero-copy-one-copy memory architecture, and integrated error management. In this paper, we describe how to minimize the transport level protocol processing using NLF. In particular, we look at how NLF is implemented, and we present performance measurements indicating a large performance gain. The protocol execution is minimized to about 450 cycles per packet regardless of packet size, i.e., a reduction of about 87% compared to 1 KB packets and more using larger packets. Consequently, the total server-side processing overhead is decreased by at least 50%.

Từ khóa

#Protocols #Intelligent networks #Network servers #Communication system operations and management #Application software #Error correction #Memory management #Memory architecture #Operating systems #Central Processing Unit

Tài liệu tham khảo

halvorsen, 2001, Improving I/O Performance of Multimedia Servers 10.1002/spe.4380230205 10.1145/166237.166262 10.1109/90.556340 10.1147/rd.422.0219 mckusick, 1996, The Design and Implementation of the 4 4 BSD Operating System ousterhout, 1990, Why Aren't Operating Systems Getting Faster As Fast As Hardware?, Proc 1990 Summer USENIX Technical Conf, 247 pai, 1999, IO-Lite: A Unified I/O Buffering and Caching System, Proc Third Usenix Symp Operating Systems Design and Implementation (OSDI'99), 15 10.1007/3-540-63875-X_50 plagemann, 2000, Operating System Support for Multimedia Systems, The Computer Communications Journal, 23, 267, 10.1016/S0140-3664(99)00180-2 braden, 1988, Computing the Internet checksum beauduy, 1999, Protocols Aboard Network Interface Cards, Proceedings of the IASTED International Conference on Parallel and Distributed Computing and Systems 10.1145/99508.99553 10.1109/35.29545 10.1109/RTTAS.2000.852466 10.1109/65.224054 10.1109/49.215015 halvorsen, 2000, Network Level Framing in INSTANCE, Proceedings of the 6th International Workshop on Multimedia Information Systems 2000 (MIS 2000), 82 2001, 3Com Gigabit Etherlink Server Network Interface Card (3C985B-SX) - Product Details 10.1007/3-540-40002-8_4 shivam, 2001, EMP: Zero-copy OS-bypass NIC-driven Gigabit Ethernet Message Passing, Proceedings of the Conference on Supercomputing (SC2001), 10.1145/582034.582091 10.1109/JSAC.1985.1146219 10.1145/347059.347561 stevens, 1998, UNIX Network Programming Networking APIs Sockets and XTI Volume 1 wright, 1995, TCP/IP Illustrated Volume 2 The Implementation wolman, 1994, Latency Analysis of TCP on an ATM Network, Proceedings of the 1994 USENIX Winter Technical Conference, 167