Athanasios E. Papathanasiou


Computer Studies Building                          Office: (585) 275-4860
Department of Computer Science                     Home: (585) 424-7521
University of Rochester                            Fax: (585) 273-4556
PO Box 270226                                      Email: papathan@cs.rochester.edu
Rochester, NY 14627                                URL: http://www.cs.rochester.edu/u/papathan
                                                   Citizenship: Greek; Visa: F-1

Research Interests

Power-efficient system design, operating systems, storage and file system design, resource discovery, distributed systems

Education

University of Rochester, Rochester, NY
Advisor: Michael L. Scott
Dissertation: ``Energy-efficient Prefetching and Caching''
The dissertation focuses on the challenges, related to prefetching and caching in modern operating systems, that are raised by the necessity for energy efficiency in mobile computing platforms. One product of the dissertation is the design of a novel memory management system in the Linux operating system that takes into account the power saving and performance capabilities of the underlying storage devices (hard disks, wireless cards) and generates access patterns that lead to significantly increased energy savings with minimal or no performance loss. Two important features of the new memory management system are that energy savings scale as memory size increases and that it leads to significantly more energy savings than power saving policies implemented at the driver or device controller level. In addition, the dissertation explores strategies for reducing the power consumption of storage systems in data centers. The main idea involved the use of a limited number of mirrored low-power disks in place of each server-class disks in order to save power by taking advantage of the workload variation in modern server systems.

University of Crete - Heraklion, Greece
M.Sc. in Computer Science awarded July 1999. Advisor: Evangelos P. Markatos
M.Sc. Thesis: ``Effective Resource Discovery on the World Wide Web''
Designed and implemented two tools, USEwebNET and Paperfinder, that facilitate resource discovery on the world wide web. USEwebNET and Paperfinder build on the idea of Usenet News. They allow users to register their interests, in a way similar to subscribing to a Usenet newsgroup. In addition, by using the existing search engine and digital library infrastructure they provide only the newest online information related to the topics of interest.

University of Crete - Heraklion, Greece
B.Sc. in Computer Science awarded November 1997. Advisor: Evangelos P. Markatos
B.Sc. Thesis: ``Lightweight Transactions on Networks of Workstations''
Designed and implemented a reliable memory layer to support in-memory Database systems and PERSEAS: a user-level library of lightweight, atomic and reliable transactions.

Honors

Winner of USENIX'04 Best Paper Award (June 2004). Award from the Greek Mathematics Association for performance in the 1992 National Mathematics Competition (May 1992).

Experience


University of Rochester, Rochester, NY 		Sep 1999--present 
Description available under the Ph.D. dissertation desciption above.


IBM Austin Research Laboratory, Austin, TX 		May 2001--Aug 2001
Research Intern--System's Group, Advisor: Eric Van Hensbergen. Design and Implementation of KNITS: a switch-based connection hand-off mechanism. KNITS is a mechanism that allows nodes to hand-off active TCP connections by utilizing connection splicing at an edge-switch serving as a gateway to a cluster. It is primarily intended to be used as part of a content aware request distribution strategy. It allows multiple TCP hand-offs per active connection.


Microsoft Research, Redmond, WA 		May 2000--Jul 2000 
Research Intern--System's and Networking Group, Mentor: John Douceur. Designed a portion of the reliability control system of the FarSite file system. FarSite is a highly-scalable distributed serverless file system. One of its goals is to provide high availability and reliability guarantees through replication, while minimizing the total amount of storage space required by avoiding keeping several copies of identical files. The reliability control system controls the number of replicas required in order to provide the specified reliability and availability guarantees. Link: http://www.research.microsoft.com/sn/Farsite/


University of Rochester, Rochester, NY 		Sep 2000--present 
Teaching assistant for four semesters in undergraduate and graduate courses. Graded homework and projects, gave tutorials and lectures, and assisted students as necessary.

Institute of Computer Science - FORTH, Heraklion, Greece 		Oct 1997--Aug 1999 
Research assistant--Computer Architecture and VLSI Group. Advisor: Evangelos P. Markatos. Involved in the design and implementation of several research projects: (a) Wormhole IP over ATM: Implementation of all the software necessary to control and experiment with the prototypes of the wormhole IP over ATM routing filter (http://archvlsi.ics.forth.gr/wormholeIP/index.html), (b) Resource Discovery on the WWW (http://archvlsi.ics.forth.gr/OS/usewebnet.html), (c) Latency reduction for the WWW: involved in the development and maintenance of Palantir: a Visualization Tool for the World Wide Web (http://archvlsi.ics.forth.gr/OS/www.html).


Institute of Computer Science - FORTH, Heraklion, Greece 		Nov 1996--Sep 1997 
Undergraduate Trainee--Computer Architecture and VLSI Group. Advisor: Evangelos P. Markatos. Description available under the M.Sc. thesis desciption above.


Institute of Computer Science - FORTH, Heraklion, Greece 		Jun 1995--Oct 1996 
Undergraduate Trainee--Computer Architecture and VLSI Group. Advisor: Dimitrios N. Serpanos. Preparation and administration of the laboratory for a course on Microprocessor Systems. Administration of a Laboratory consisting of four Cyclone Evaluation Boards with Intel i960 microprocessors connected to Pentium PCs. Authored parts of the course handouts and created the course's assignments.


University of Crete, Heraklion, Greece 		Sep 1995--Jun 1999 
Teaching assistant for six semesters in undergraduate and graduate courses related to computer architecture, operating systems, parallel and distributed systems, processor design. Graded homework and projects, gave tutorials and lectures, and assisted students as necessary.

Activities

Served as a student member of the Graduate Admissions Committee of the Computer Science Dept. at the University of Rochester for four consecutive years. Organized systems group meetings for one year. Served as a volunteer at SOSP'03. Served as a scribe at SOSP'01 and WMCSA'03. Student member of ACM, IEEE and Usenix. Reviewed papers for IEEE TPDS, IEEE Computer, HPCA'03, ISCA'03, MobiSys'04, NPC'04, ICPADS'04, IPDPS'04, HotOs-VIII and other forums.

Publications

All publications are available at http://www.cs.rochester.edu/u/papathan/papers/.
Invited book chapters
  1. ``On Using Reliable Network RAM in Networks of Workstations'' by Sotiris Ioannidis, Athanasios E. Papathanasiou, Grigorios I. Magklis, Evangelos P. Markatos, Dionisios N. Pnevmatikatos, and Julia Sevaslidou. Cluster Computing pp. 109-121, Chapter 10, 2001, ISBN 1-59033-113-3, Nova Science Publishers, USA.

Journals
  1. ``Visualizing Traffic on the World Wide Web'' by Evangelos P. Markatos, Athanasios E. Papathanasiou and Nektarios Papadakakis. WebNet Journal: Internet Technologies, Applications and Issues, April-June 1999, Vol. 1, No. 2, pp. 57-65.
  2. ``On Using Reliable Network RAM in Networks of Workstations'' by Sotiris Ioannidis, Athanasios E. Papathanasiou, Grigorios I. Magklis, Evangelos P. Markatos, Dionisios N. Pnevmatikatos, and Julia Sevaslidou. Special Issue on High Performance Computing on Clusters Parallel and Distributed Computing Practices (PDCP) (Vol 2, No 2), Nova Science Publishers, USA, February 1999.

Other refereed publications
  1. ``Aggressive Prefetching: An Idea Whose Time Has Come'' by Athanasios E. Papathanasiou and Michael L. Scott. To appear in Proceedings of the Tenth Workshop on Hot Topics in Operating Systems (HotOS X), June 12-15, 2005, Eldorado Hotel, Santa Fe, NM.
  2. ``Competitive Prefetching for Data-Intensive Online Servers'' by Chuanpeng Li, Athanasios E. Papathanasiou and Kai Shen. Proceedings of the First Workshop on Operating System and Architectural Support for the on demand IT Infrastructure (OASIS'04), (Held along with ASPLOS-XI), October 9-13, 2004, Boston, MA, USA. An extended version appears as: Technical Report 840, Computer Science Department, University of Rochester, August 2004.
  3. ``Energy Efficient Prefetching and Caching'' by Athanasios E. Papathanasiou and Michael L. Scott. Proceedings of the USENIX 2004 Annual Technical Conference (USENIX'04), June 27-July 2, 2004, Boston Marriott Copley Place, Boston, MA, USA. Winner: USENIX'04 Best Paper Award.
  4. ``Energy Efficient Prefetching and Caching'' by Athanasios E. Papathanasiou and Michael L. Scott. Poster Paper at the $19^{th}$ ACM Symposium on Operating Systems Principles (SOSP'03), The Sagamore, Bolton Landing (Lake George), New York, October 19-22, 2003.
  5. ``Energy Efficiency through Burstiness'' by Athanasios E. Papathanasiou and Michael L. Scott. Proceedings of the $5^{th}$ IEEE Workshop on Mobile Computing Systems and Applications (WMCSA'03), October 9-10, 2003, Monterey, California, USA.
  6. ``KNITS: Switch-based Connection Hand-off'' by Athanasios E. Papathanasiou and Eric Van Hensbergen. Proceedings of the $21^{st}$ Annual Joint Conference of the IEEE Computer and Communications Societies (Infocom'02), New York, NY, USA, June 2002.
  7. ``Effective Resource Discovery on the World Wide Web'' by Evangelos P. Markatos, Christina Tziviskou and Athanasios E. Papathanasiou. Proceedings of WebNet'98-World Conference of the WWW, Internet, and Intranet, pp. 611-616, Vol. I, Orlando, Florida, USA, November 1998. Also appeared as work in progress report in the $2^{nd}$ USENIX Symposium on Internet Technologies & Systems (USITS'99) October 11-14, 1999 Boulder, Colorado, USA.
  8. ``PaperFinder: A Tool for Scalable Search of Digital Libraries'' by Athanasios E. Papathanasiou, Evangelos P. Markatos and Stavros A. Papadakis. Short paper in WebNet 98-World Conference of the WWW, Internet, and Intranet, Orlando, Florida, USA, November 1998. Also appeared as work in progress report in the $2^{nd}$ USENIX Symposium on Internet Technologies & Systems (USITS'99) October 11-14, 1999 Boulder, Colorado, USA.
  9. ``Palantir: A Visualization Tool for the World Wide Web'' by Nektarios Papadakis, Evangelos P. Markatos and Athanasios E. Papathanasiou. Proceedings of INET'98 (The Internet Summit), Geneva, Switzerland, July 1998.
  10. ``Lightweight Transactions on Networks of Workstations'' by Athanasios E. Papathanasiou and Evangelos P. Markatos. Proceedings of the $18^{th}$ International Conference on Distributed Computing Systems (ICDCS'98), Amsterdam, May 1998. An extended version appears as: Technical Report 209, ICS-FORTH, September 1997.
  11. ``On using Reliable Network RAM for Database Systems'' by Athanasios E. Papathanasiou and Evangelos P. Markatos. Poster Paper at the $16^{th}$ Symposium on Operating System Principles (SOSP'97), Saint Malo, France, October 1997.

Unrefereed or lightly refereed
  1. ``Power-efficient Server-class Performance from Arrays of Laptop Disks'' by Athanasios E. Papathanasiou and Michael L. Scott. Technical Report 837, Computer Science Department, University of Rochester, May 2004. Work in progress presentation at the USENIX 2004 Annual Technical Conference (USENIX'04), June 27-July 2, 2004, Boston Marriott Copley Place, Boston, MA, USA
  2. ``Mobile Computing at the Beach'' by Justin Mazzola Paluska, Angela Dalton, Prasad Boddupalli, Amit Saha, Athanasios E. Papathanasiou and Santashil Palchaudhuri. IEEE Pervasive Computing (Vol. 3, No. 1), January-March 2004, pp. 89-92.
  3. ``Increasing File System Burstiness for Energy Efficiency'' by Athanasios E. Papathanasiou and Michael L. Scott. Technical Report 792, Computer Science Department, University of Rochester, November 2002. Work in progress presentation at the 5th Symposium on Operating Systems Design and Implementation (OSDI'02), Boston, MA, December 2002.
  4. ``On the Power Consumption of Computing Systems'' by Athanasios E. Papathanasiou. Systems Area Paper, University of Rochester, May 2001.

References

Michael L. Scott, Professor
Computer Studies Building
Department of Computer Science
University of Rochester
160 Trustee Road
Rochester, NY, 14627-0226
Email: scott@cs.rochester.edu
Phone: (585) 275-7745
Fax: (585) 273-4556

Sandhya Dwarkadas, Associate Professor
Computer Studies Building
Department of Computer Science
University of Rochester
160 Trustee Road
Rochester, NY, 14627-0226
Email: sandhya@cs.rochester.edu
Phone: (585) 275-5647
Fax: (585) 273-4556

Kai Shen, Assistant Professor
Computer Studies Building
Department of Computer Science
University of Rochester
160 Trustee Road
Rochester, NY, 14627-0226
Email: kshen@cs.rochester.edu
Phone: (585) 275-5426
Fax: (585) 273-4556

Evangelos P. Markatos, Associate Professor
Head, W3C Office in Greece
Head, Advanced Computing Systems Research Group
Institute of Computer Science (ICS)
FORTH P.O.Box 1385
Heraklio, Crete, GR-711-10, GREECE
Email: markatos@ics.forth.gr
Phone: +30 (2810) 391655
Fax: +30 (2810) 391661

Eric Van Hensbergen, Advisory Software Engineer
IBM Austin Research Lab
11501 Burnet Road
Austin, TX 78758
Email: bergevan@us.ibm.com
Phone: (512) 838-0717
Fax: (512) 838 4036



Athanasios E. Papathanasiou 2004-11-21