College of Computer Science Colloquium

Regular Meeting Time:

Wednesdays, 3pm -4pm, 107 Cullinane. Refreshments at 4pm. Colloquia are not scheduled for every Wednesday.

Organizer:

Betty Salzberg
College of Computer Science, Northeastern University
360 Huntington Avenue #161CN,
Boston, MA 02115
Internet: salzberg@ccs.neu.edu
Phone: (617) 373-2229 / Fax: (617) 373-5121

[College of Computer Science | Northeastern University]


Next Colloquium:

Title: Revisiting Commit Processing in Distributed Database Systems

Speaker: Jayant Haritsa
Supercomputer Education and Research Centre
and
Department of Computer Science and Automation
Indian Institute of Science
Bangalore, INDIA

Time and Place: FRIDAY May 2 at 2pm in 107CN
Northeastern University
(Note unusual day and time)

Abstract:

A significant body of literature is available on distributed transaction commit protocols. Surprisingly, however, the relative merits of these protocols have not been studied with respect to their quantitative impact on transaction processing performance. In this talk, using a detailed simulation model of a distributed database system, we will profile the transaction throughput performance of a representative set of commit protocols. A new commit protocol, OPT, that allows transactions to ``optimistically'' borrow uncommitted data in a controlled manner is also proposed and evaluated. The new protocol is easy to implement and incorporate in current systems, and can coexist with most other optimizations proposed earlier. For example, OPT can be combined with current industry standard protocols such as Presumed Commit and Presumed Abort.

The experimental results show that distributed commit processing can have considerably more influence than distributed processing on the throughput performance and that the choice of commit protocol clearly affects the magnitude of this influence. Among the protocols evaluated, the new optimistic commit protocol provides the best transaction throughput performance for a variety of workloads and system configurations. In fact, OPT's peak throughput is often close to the upper bound on achievable performance. Even more interestingly, a three-phase (i.e., non-blocking) version of OPT provides better peak throughput performance than all of the standard two-phase (i.e., blocking) protocols evaluated in our study.

(This is joint work with Ramesh Gupta and Krithi Ramamritham.)

Jayant Haritsa is an Assistant Professor in the Supercomputer Education & Research Centre and in the Department of Computer Science & Automation at the Indian Institute of Science, Bangalore. He received the B.S. degree in Electronics and Communications Engineering from the Indian Institute of Technology (Madras) in 1985. He received the M.S. and Ph.D. degrees in Computer Science from the University of Wisconsin (Madison) in 1987 and 1991, respectively. From 1991 to 1993, he was a Post-Doctoral Fellow with the Systems Research Center at the University of Maryland (College Park). During 1988 and 1990, he spent summers at the Microelectronics and Computer Technology Consortium in Austin, Texas, and at the IBM T.J. Watson Research Center in New York, respectively. His research interests are in database systems and real-time systems. He is a member of IEEE and ACM.

Host: Betty Salzberg


Schedule of Forthcoming Colloquia:

No further Colloquia currently planned for Spring 1997.


Some previous Colloquia:

September, 1995: Joe Stoy, Oxford: The semantics of pH

Oct 18, 1995: Butler Lampson, Microsoft : How to build a highly available system without a toolkit

Nov 1, 1995: Henry Prakken, Free U. Amsterdam: Defeasible argumentation and case-based reasoning in Law

Nov 15, 1995: Jens Palsberg, NU and MIT: Type Inference for objects

February 14, 1996: Azer Bestavros, BU: Server-Initiated Replication and Prefetching in WWW Distributed Information Systems

February 21, 1996: Dennis Shasha, NYU: The Cube Forest

February 26, 1996: Isaac Saias, Los Alamos: Randomized Optimal Scheduling by Replacement

March 6, 1996: Dennis Miller, NU: Sound Synthesis using Csound

April 10, 1996: Barbara Liskov, MIT: Safe sharing with Thor

April 24: David Sonnenschein, NU : The Anatomy of Music: A Multimedia Approach to Music Cognition

May 8: Vassilis Tsotras, Polytechnic Univ: Access Methods for Temporal Databases

October 30, 1996: Alan Fekete, Sydney University, Formal Methods and Transaction Management

November 13, 1996: Mark Crovella, Boston University, Network Traffic Self-Similarity and the World Wide Web

November 20, 1996, Arnie Rosenthal, The MITRE Corporation, Data Administration for Large-Scale Systems

November 22, 1996, John Reif, Duke University, Models for Molecular Parallelism

December 4, 1966, Prof. Chris Dellarocas, Sloan School of Management, "Towards a Design Handbook for Integrating Software Components"

Dec 9, 1996: Prof. Carolyn Talcott, Stanford University, "Reasoning about Functions with Effects"

Dec 11, 1996: Prof. Elke Rundenstein, WPI, "MultiMedia Data Exploration in MMVIS: A Visual Query Paradigm for Temporal Trend Discovery"

Jan 15, 1997: Prof. Krithi Ramamrithan, U Mass Amhearst, "Database Issues in Real-time applications"

March 5, 1997: Prof. Jim Kurose, U. Mass Amherst, multi-media and high-performance networking protocols

April 14, 1997: Dr. Liuba Shrira
MIT Lab for Computer Science
Cache Structure for Large-Scale Object
Storage Systems

April 23, 1997:Jack Orenstein
Novera Software, Inc.
A High-Performance, Transparent, Object-Oriented Interface to Relational Databases

Dr. Pravin Bhagwat
IBM, Thomas J. Watson Research Ctr.
Wireless and Mobile Network Architecture Group
Mobile Networking: Mobile IP and beyond