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Mariposa: a wide-area distributed database system

Bans on millions of commonly owned rifles, shotguns and handguns bans on tens of millions of standard magazines bans on private transfers, even between family members import bans a federal database to track firearms and their owners in other words, the national registration of every single gun owner in the country. It was only a few weeks ago when they were marketing their anti-gun agenda as a way of protecting schoolchildren from harm. That charade ended at the State of the Union, when the president himself exposed their fraudulent intentions. It’s not. | The VLDB Journal 1 Springer-Verlag 1996 The VLDB Journal 1996 5 48-63 Mariposa a wide-area distributed database system Michael Stonebraker Paul M. Aoki Witold Litwin1 Avi Pfeffer2 Adam Sah Jeff Sidell Carl Staelin3 Andrew Yu4 Department of Electrical Engineering and Computer Sciences University of California Berkeley CA 94720-1776 USA Edited by Henry F. Korth and Amit Sheth. Received November 1994 Revised June 1995 Accepted September 14 1995 Abstract. The requirements of wide-area distributed database systems differ dramatically from those of local-area network systems. In a wide-area network WAN configuration individual sites usually report to different system administrators have different access and charging algorithms install site-specific data type extensions and have different constraints on servicing remote requests. Typical of the last point are production transaction environments which are fully engaged during normal business hours and cannot take on additional load. Finally there may be many sites participating in a WAN distributed DBMS. In this world a single program performing global query optimization using a cost-based optimizer will not work well. Cost-based optimization does not respond well to sitespecific type extension access constraints charging algorithms and time-of-day constraints. Furthermore traditional cost-based distributed optimizers do not scale well to a large number of possible processing sites. Since traditional distributed DBMSs have all used cost-based optimizers they are not appropriate in a WAN environment and a new architecture is required. We have proposed and implemented an economic paradigm as the solution to these issues in a new distributed DBMS called Mariposa. In this paper we present the architecture and implementation of Mariposa and discuss early feedback on its operating characteristics. Key words Databases - Distributed systems - Economic site - Autonomy - Wide-area network - Name service 1 Present address Universite