Saturday, April 20, 2013

Yoav Raz - From Amazon Wiki

Copied from

Yoav Raz

Yoav Raz (Hebrew: יואב רז‎, born 1947, Haifa, Israel) is a computer scientist. He has worked primarily in the area of Information technology, and conducted research mainly in Data management (Databases in particular). He was Chief Scientist at EMC Corporation (1994–2003).
Yoav Raz is the inventor of Commitment ordering[1][2][3][4][5] (Commit ordering; CO; in 1990), a new class of interoperable concurrency control (Serializability) techniques. The CO techniques have solved[6] a years old practical fundamental open problem in concurrency control of database management systems: The Global serializability problem.[7] With the proliferation of Multi-core processors Raz's generic local CO algorithm has also been increasingly utilized in Concurrent programming, Transactional memory, and especially in Software transactional memory (STM) for achieving serializability optimistically.[8][9]
He is also the inventor of other widely cited[10] patents[11] and the author of academic articles.[12] Since 1986 he has mainly resided in the USA.
Yoav Raz received his academic degrees, B.Sc. (1969), M.Sc. (1973), and D.Sc. (1979), from the Technion – Israel Institute of Technology in Haifa.[13] He studied for his B.Sc while serving in the Atuda (academic reserve program of the Israel Defense Forces) after graduating the Leo Baeck high-school[14] in Haifa (1965), and before his military service (1970–1975).




Work history

Dr. Raz is Senior partner at Raz consulting[15] (since 2003).
Previously he was Chief Scientist at EMC Corporation (Computer data storage and related technologies; reporting to Moshe Yanai; nine years), and this after holding the position of Software architect at Digital Equipment Corporation (DEC; Transaction processing - Technology, Architecture, and Standards Group, and a representative at ANSI and ISO/OSI; six years). Before this he was Co-founder and Managing director at Sitav Ltd. (an information technology consultancy, systems developer, and software companies representative in Israel; ten years).
He also held academic positions (with partial overlap): Visiting Associate Professor at the University of California, San Diego (UCSD; total of three years), and before this Senior lecturer at the Technion – Israel Institute of Technology (seven years).


Major published results with practical applications:


Commitment ordering

also called Commit ordering (CO)
See also Transactional locking in Software transactional memory
In 1990, while at Digital Equipment Corporation (DEC), Yoav Raz discovered Commitment ordering [1][2] (Commit ordering; CO), a Serializability implying database schedule property, and invented[4][5] related effective interoperable concurrency control techniques for guaranteeing Serializability, Distributed serializability, and Global serializability[6] (the CO schedule property has been discovered independently of an equivalent property, Dynamic atomicity, which has been defined for Abstract data types without generic algorithms, and its equivalent to CO version can be traced to 1988[16]).
Yoav Raz is also the developer of the underlying Theory of Commitment ordering[3] (now a substantial part of serializability theory), which explains CO's properties and mechanisms' correctness. CO (including its special case SS2PL) is potentially (and probably) the major general concurrency control (serializability) method for the emerging Cloud computing.


General theory of multi-version concurrency control

See Multi-version CO (MVCO) in Commitment ordering
and Making Snapshot Isolation Serializable in Snapshot isolation
Raz also developed a new, revised General theory of multi-version concurrency control, which is a natural generalization of the common single-version concurrency control theory. This theory has allowed to define Multi-version CO (MVCO) for the first time, to make single-version CO (the common CO) a special case of (the generalizing) MVCO. It also allows a unified handling of both single and multi-version database objects, and the transparent inter-operation among their respective concurrency control methods. The new element in the theory is the way conflicts are defined.[17]
The new theory has been utilized (without CO) also for analyzing and enhancing the popular multi-version based Snapshot Isolation (SI) concurrency control method to make it serializable. It is referenced in related publications, e.g., (Cahill et al. 2008),[18] and explicitly outlined in a presentation in (Fekete 2009)[19] which summarizes years of research on making SI serializable.


The dynamic two-phase commit protocol

Yoav Raz coined the name Dynamic Two-Phase Commitment Protocol (D2PC) and proved the protocol's time optimality[20] (fastest commit possible of each distributed transaction's participant by dynamically letting the commit coordinator to be chosen optimally at the location of collision of racing protocol messages (votes) over the transaction's communication tree). He took part (in 1992-3, as the US (ANSI) head of delegation, with all the major computer companies participating) in the standardization process of D2PC by the ISO-IEC/JTC1/OSI-DTP&CCR groups in a project on commitment optimizations (commit optimizations) for their respective standards (the original underlying communication standards for the de-facto standard X/Open DTP and the origins of its model).


Preparatory operations for B-tree concurrency control

Yoav Raz [with his graduate student] coined the term Preparatory Operations for the concurrency control of B-trees (a common database indexing method; specifically: the B+-tree (B+ tree) variant), demonstrated these operations within a concurrency control protocol, and showed its performance advantage over previously known protocols.[21]



Yoav Raz is co-developer of ERROL- an Entity Relationship Role Oriented Language,[22] developed and implemented together with his graduate students at Technion and UCSD. The essence of ERROL is based on the M.Sc. project of Victor M. Markowitz. ERROL is a declarative database language over the Entity-Relationship Model (ERM) that mimics Natural language constructs (specifically, the English language, however other natural languages can be used as well). ERROL's expressions look like, and usually are identical to Natural language sentences. ERROL's semantics and processing are defined by an underlying Reshaped relational algebra[23] (RRA) with relational operators that bear analogies to major Natural language constructs. RRA has been developed by Victor Markowitz in conjunction with the development of ERROL and later has been reformulated by Yoav Raz.[24] Being close to natural languages, ERROL allows a relatively convenient for humans formulation of complex database queries, and can be a foundation for convenient to use data management languages.
Yoav Raz and his students Victor M. Markowitz and Reuven Cohen won for ERROL the 1984 Computer Science Award by ILA – The Israeli Information Technology Association.




  1. ^ a b Yoav Raz (1992): "The Principle of Commitment Ordering, or Guaranteeing Serializability in a Heterogeneous Environment of Multiple Autonomous Resource Managers Using Atomic Commitment" (PDF), Proc. of the Eighteenth Int. Conf. on Very Large Data Bases (VLDB), pp. 292-312, Morgan Kaufmann, Vancouver, Canada, August 1992. (also DEC-TR 841 (PDF), Digital Equipment Corporation, November 1990)
  2. ^ a b Yoav Raz (1994): "Serializability by Commitment Ordering", Information Processing Letters, Volume 51, Number 5, pp. 257-264, September 1994. (Received August 1991)
  3. ^ a b Yoav Raz (2009): Theory of Commitment Ordering - Summary GoogleSites - Site of Yoav Raz. Retrieved 1 Feb, 2011.
  4. ^ a b Yoav Raz (1990): On the Significance of Commitment Ordering - Call for patenting, Memorandum, Digital Equipment Corporation, November 1990.
  5. ^ a b Yoav Raz (1991): US patents 5,504,899 (ECO) 5,504,900 (CO) 5,701,480 (MVCO)
  6. ^ a b Philip A. Bernstein, Eric Newcomer (2009): Principles of Transaction Processing, 2nd Edition, Morgan Kaufmann (Elsevier), June 2009, ISBN 978-1-55860-623-4  (pages 145, 360)
  7. ^ Abraham Silberschatz, Michael Stonebraker, and Jeffrey Ullman (1991): "Database Systems: Achievements and Opportunities", Communications of the ACM, Vol. 34, No. 10, pp. 110-120, October 1991 (page 120)
  8. ^ Hany E. Ramadan, Indrajit Roy, Maurice Herlihy, Emmett Witchel (2009): "Committing conflicting transactions in an STM" (PDF) Proceedings of the 14th ACM SIGPLAN symposium on Principles and practice of parallel programming (PPoPP '09), ISBN 978-1-60558-397-6
  9. ^ Lingli Zhang, Vinod K.Grover, Michael M. Magruder, David Detlefs, John Joseph Duffy, Goetz Graefe (2006): Software transaction commit order and conflict management United States Patent 7711678, Granted 05/04/2010.
  10. ^ Yoav Raz - Google scholar See citations; Retrieved 13 November, 2011.
  11. ^ Yoav Raz: Patents at
  12. ^ Yoav Raz: Partial list of publications from the DBLP Bibliography Server
  13. ^ Yoav Raz at the Mathematics Genealogy Project.
  14. ^ Leo Baeck Education Center - History Retrieved 24 February 2011.
  15. ^ Site of Raz Consulting Retrieved 5 March 2011.
  16. ^ Alan Fekete, Nancy Lynch, Michael Merritt, William Weihl (1988): Commutativity-based locking for nested transactions (PDF) MIT, LCS lab, Technical report MIT/LCS/TM-370, August 1988, page 43.
  17. ^ Yoav Raz (1993): "Commitment Ordering Based Distributed Concurrency Control for Bridging Single and Multi Version Resources." Proceedings of the Third IEEE International Workshop on Research Issues on Data Engineering: Interoperability in Multidatabase Systems (RIDE-IMS), Vienna, Austria, pp. 189-198, April 1993. (also DEC-TR 853 (PDF), Digital Equipment Corporation, July 1992)
  18. ^ Michael J. Cahill, Uwe Röhm, Alan D. Fekete (2008) "Serializable isolation for snapshot databases", Proceedings of the 2008 ACM SIGMOD international conference on Management of data, June 10–12, 2008, Vancouver, Canada, pp. 729-738, ISBN 978-1-60558-102-6 (SIGMOD 2008 best paper award)
  19. ^ Alan Fekete (2009), "Snapshot Isolation and Serializable Execution", Presentation, 2009, The university of Sydney (Australia). Retrieved 16 September 2009 (Page 4)
  20. ^ Yoav Raz (1995): "The Dynamic Two Phase Commitment (D2PC) protocol ",Database Theory — ICDT '95, Georg Gottlob, Moshe Y. Vardi (Eds.): Proceedings of the 5th International Conference on Database Theory, Prague, Czech Republic, January 11–13, 1995, Lecture Notes in Computer Science, Volume 893/1995, pp. 162-176, Springer, ISBN 978-3-540-58907-5  (Also DEC-TR 871 (PDF), Digital Equipment Corporation, 1993)
  21. ^ Yehudit Mond, Yoav Raz (1985): "Concurrency Control in B+-trees Databases Using Preparatory Operations" (PDF), Proc. of the Eleventh Int. Conf. on Very Large Data Bases (VLDB), pp. 331-334, Morgan Kaufmann, Stockholm, Sweden, August 1985.
  22. ^ Victor M. Markowitz, Yoav Raz (1983): "ERROL - An Entity Relationship Role Oriented Query Language", In Entity Relationship Approach to Software Engineering (ER 1983), October 5–9, Anaheim, California. Davis, G.C. et al. (eds.), pp. 329–345, North- Holland.
  23. ^ Victor M. Markowitz, Yoav Raz (1984): "An entity-relationship algebra and its semantic description capabilities", Journal of Systems and Software, Volume 4, Issues 2-3, pp. 147-162, Elsevier Science Inc., July 1984.
  24. ^ Yoav Raz (1986): A Precise Definition of RRA - a Reshaped Relational Algebra which Follows Natural Language Constructs (pdf), Technical Report TR #405, Computer Science Dept., Technion, Israel, March 1986.

External links

No comments: