|
FAST '04 — Abstract
Pp. 201-212 of the Proceedings
Circus: Opportunistic Block Reordering for Scalable Content Servers
Stergios V. Anastasiadis, Rajiv G. Wickremesinghe, and Jeffrey S. Chase, Duke University
Abstract
Whole-file transfer is a basic primitive for Internet content dissemination. Content servers are increasingly limited by disk arm movement given the rapid growth in disk density, disk transfer rates, server network bandwidth, and content size. Individual file transfers are sequential, but the block access sequence on a content server is effectively random when many slow clients access large files concurrently. Although larger blocks can help improve disk throughput, buffering requirements increase linearly with block size.
This paper explores a novel block reordering technique that can reduce server disk traffic significantly when large content files are shared. The idea is to transfer blocks to each client in any order that is convenient for the server. The server sends blocks to each client opportunistically in order to maximize the advantage from the disk reads it issues to serve other clients accessing the same file. We first illustrate the motivation and potential impact of opportunistic block reordering using a simple analytical model. Then we describe a file transfer system using a simple block reordering algorithm, called Circus. Experimental results with the Circus prototype show that it can improve server throughput by a factor of two or more in workloads with strong file access locality.
- View the full text of this paper in HTML and
PDF.
Until March 2005, you will need your USENIX membership identification in order to access the full papers. The Proceedings are published as a collective work, © 2004 by the USENIX Association. All Rights Reserved. Rights to individual papers remain with the author or the author's employer. Permission is granted for the noncommercial reproduction of the complete work for educational or research purposes. USENIX acknowledges all trademarks within this paper.
- If you need the latest Adobe Acrobat Reader, you can download it from Adobe's site.
|
Need help? Use our Contacts page.
