Repeating History Beyond ARIES

C. Mohan
IBM Almaden Research Center


In this talk, I describe first the background behind the development of the original ARIES recovery method, and its significant impact on the commercial world and the research community. Next, I provide a brief introduction to the various concurrency control and recovery methods in the ARIES family of algorithms. Subsequently, I discuss some of the recent developments affecting the transaction management area and what these mean for the future. In ARIES, the concept of repeating history turned out to be an important paradigm. As I examine where transaction management is headed in the world of the internet, I observe history repeating itself in the sense of requirements that used to be considered significant in the mainframe world (e.g., performance, availability and reliability) now becoming important requirements of the broader information technology community as well.


Dr. C. Mohan joined the Computer Science Department of the IBM Almaden Research Center as a Research Staff Member in 1981. In 1997, Mohan was named to IBM's highest technical position of an IBM Fellow for being recognized worldwide as a leading innovator in transaction management. He received the ACM SIGMOD Innovations Award in 1996 in recognition of his innovative contributions to the development and use of database systems. At VLDB99, he was honored with the 10 Year Best Paper Award for the impact of his work on the ARIES family of algorithms. In 1992, Mohan was elected a member of the IBM Academy of Technology. Since late 1996, Mohan has been leading the Dominotes project whose goal is to enhance Lotus Domino/Notes's scalability and fault tolerance by introducing transactional recovery in Domino R5. Earlier, Mohan led the Exotica project which was focused on advanced transaction management and on IBM's workflow product FlowMark, messaging product MQSeries and groupware product Lotus Notes. During 1998-99, he was on a sabbatical at INRIA, Rocquencourt (France). Mohan was a designer and an implementor of the R* distributed DBMS, the Starburst extensible DBMS and DB2. He is the primary inventor of the ARIES family of recovery and concurrency control methods, and the Presumed Abort commit protocol. He has lectured extensively, and authored numerous conference and journal papers on concurrency control, recovery, commit protocols, index management, query optimization, active databases, architectural support for transaction processing, parallelism, OODBMSs, client-server computing, remote-site backup, workflow, data sharing and distributed systems. He is a consultant for numerous IBM database, transaction processing and workflow product groups. His research ideas have been incorporated in the IBM products DB2/MVS, DB2 Common Server (DB2/NT, DB2/6000, ...), SQL/DS, IMS/ESA, MQSeries, S/390Parallel Sysplex Coupling Facility, Lotus Notes/Domino, VM Shared File System, AdStar Distributed Storage Manager (ADSM) and Workstation Data Save Facility (WDSF/VM), in the IBM prototypes R*, Starburst and QuickSilver, and in IBM's SNA LU6.2 and DRDA architectures.

Mohan is the recipient of several IBM awards: an IBM Corporate Award for database support for parallel sysplex; an IBM Outstanding Innovation Award (OIA) for his coinvention of the ARIES recovery method which is being used in several IBM products, in Transarc'sEncina Product Suite, and in the University of Wisconsin's Gamma and EXODUS DBMSs, and SHORE persistent object system; an OIA for his inventions (ARIES, ARIES/IM, Commit_LSN) and major contributions to performance, availability and concurrency in DB2/MVS V4; three OIAs for his algorithmic and hardware architectural coinventions for supporting the shared disks transaction environment in S/390 and DB2/MVS; an OIA for his coinvention of the Hybrid Join method which is implemented in DB2/MVS; an OIA for his coinvention of the Presumed Abort commit protocol which has been widely adopted in the industry and which is now part of the ISO-OSI, X/Open and DRDA distributed transaction processing standards; an IBM Research Division Award (RDA) for his work on transaction management in R*; an RDA for his contributions to WDSF/VM; 9th Plateau IBM Invention Achievement Award for his patenting activities (28 issued and 5 pending patents). Mohan was named a leading inventor of IBM for 1994 and 1995, and a Master Inventor in 1997.

Mohan was the Americas Program Chair for the 1996 International Conference on Very Large Data Bases, the Program Chair for the 1987 International Workshop on High Performance Transaction Systems and a Program Vice-Chair for the 1994 International Conference on Data Engineering. He has been on the program committees of the conferences SIGMOD, PODS, ICDE, ICDCS, VLDB, PDIS, HPTS, ADB and Compcon. He is an editor of the VLDB Journal and Distributed and Parallel Databases - An International Journal. He was an Associate Editor of IEEE's Data Engineering Bulletin. He has been a visiting scientist in Hahn-Meitner-Institut (Germany). Mohan received a PhD in Computer Science from the University of Texas at Austin in 1981 and a B.Tech. in Chemical Engineering from the Indian Institute of Technology, Madras in 1977.