Algorithms for Data Migration

Speaker:	Dr. Yung-Chun Justin Wan
		Google Inc.

Title:		"Algorithms for Data Migration"

Date:		Monday, 20 March 2006

Time:		4:00pm - 5:00pm

Venue:		Lecture Theatre F
		(Leung Yat Sing Lecture Theatre, near lift nos. 25/26)
		HKUST

ABSTRACT:

This work is motivated by the problem of managing data on storage devices,
typically a set of disks. Such high demand storage servers are often used
as multimedia servers for handling high demand for data. As the system is
running, it needs to dynamically rearrange the placement of data items to
respond to changes in demand for different items. The problem of quickly
changing one storage configuration into another is known as the data
migration problem. In this talk I will present my work on the first
polynomial-time approximation algorithm for this problem and show a worst
case bound of 9.5 on the approximation factor achieved by the algorithm. I
will also present performance evaluations of the algorithm. In addition, I
will discuss a related problem of data migration where one wants to, given
a time limit on finishing the migration, find a schedule that results in a
good storage configuration which satisfies most demands,



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Biography:

Dr. Yung-Chun Justin Wan received his Ph.D. and M.Sc. degree in Computer
Science from the University of Maryland at College Park in 2005 and 2001,
respectively, and received his B.Sc. degree from the Chinese University of
Hong Kong. He is interested in designing algorithms with applications in
networks, and specifically algorithms for data transfer problems arising
in communication networks. He interned at Xerox PARC and Bell Labs, and is
now working at Google Inc., focusing on web-spam fighting.