Towards online schedulers based on Pre-Analysis Locking

  • Georg Lausen
  • Eljas Soisalon-Soininen
  • Peter Widmayer
Contributed Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 243)


Locking is one familiar mechanism for a database concurrency control to achieve safe transaction systems. Pre-Analysis Locking bases on an algorithm which analyses a set of transactions to determine the conflicting actions. Different to known locking policies, e.g. 2-Phase Locking, the position of lock operations depends only on the location of the conflicting actions within the transactions. Therefore, depending on the structure of the transactions, Pre-Analysis Locking allows for a higher potential degree of concurrency than 2-Phase Locking. Until now Pre-Analysis Locking requires the knowledge of the complete set of transactions to be executed in advance. In this paper, iterative Pre-Analysis Locking is proposed, which manages the case of previously unknown transactions. Further, dynamic Pre-Analysis Locking is introduced, which additionally is able to forget finished transactions and therefore is an appealing new approach to online scheduling. Safety of the policies is proven and the issue of deadlock freedom is discussed.


Concurrency Control Online Schedule Conflict Graph Transaction System Deadlock Freedom 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Bayer, R., Heller, H., Reiser, A. (1980), “Parallelism and recovery in database systems,” ACM Trans. Database Syst. 5, 139–156.Google Scholar
  2. Beeri, C., Bernstein, P.A., Goodman, N., Lai, M.Y., Shasha, D.E. (1983), “A concurrency control theory for nested transactions,” Proc. 2nd ACM SIGACT-SIGOPS Symp. on Principles of Distributed ComputingGoogle Scholar
  3. Eswaran, K.P., Gray, J.N., Lorie, R.A., and Traiger, I.L. (1976), “The notions of consistency and predicate locks in a database system,” Comm. Assoc. Comput. Mach. 19, 624–633.Google Scholar
  4. Kedem, Z., and Silberschatz, A. (1980), “Non-two phase locking protocols with shared and exclusive locks,” Proc. Int. Conf. Very Large Databases.Google Scholar
  5. Korth, H.F. (1983), “Locking primitives in a database system,” J. Assoc. Comput. Mach. bf 30, 55–79.Google Scholar
  6. Lausen, G., Soisalon-Soininen, E., and Widmayer, P. (1985), “Pre-Analysis Locking: a safe and deadlock free locking policy,” Proc. Int. Conf. Very Large Databases.Google Scholar
  7. Lausen, G., Soisalon-Soininen, E., and Widmayer, P. (1986), “Pre-Analysis Locking,” Information and Control to appear 1986.Google Scholar
  8. Lipski, W., and Papadimitriou, C.H. (1981), “A fast algorithm for testing for safety and detecting deadlocks in locked transaction systems,” Journal of Algorithms 2, 211–226.Google Scholar
  9. Ottmann, Th., Soisalon-Soininen, E., and Wood, D. (1984), “On the definition and computation of rectilinear convex hulls,” Information Sciences 33, 157–171.Google Scholar
  10. Papadimitriou, C.H. (1979), “Serializability of concurrent database updates,” J. Assoc. Comput. Mach. 26, 631–653.Google Scholar
  11. Papadimitriou, C.H. (1983), “Concurrency control by locking,” SIAM J. Comput. 12, 215–226.Google Scholar
  12. Schlageter, G. (1978), “Process synchronization in database systems,” ACM Trans. Database Syst. 3, 248–271.Google Scholar
  13. Silberschatz, A., and Kedem, Z. (1980), “Consistency in hierarchical database systems,” J. Assoc. Comput. Mach. 27), 72–80.Google Scholar
  14. Weikum, G. (1986), “A theoretical foundation of multilevel concurrency control,” ACM SIGACT-SIGMOD Symp. on Principles of Database Systems.Google Scholar
  15. Yannakakis, M. (1982), “A theory of safe locking policies,” J. Assoc. Comput. Mach. 29, 718–740.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • Georg Lausen
    • 1
  • Eljas Soisalon-Soininen
    • 2
  • Peter Widmayer
    • 3
  1. 1.Institut für Programm- und InformationssystemeTechnische Hochschule DarmstadtDarmstadtWest-Germany
  2. 2.Department of Computer ScienceUniversity of HelsinkiHelsinki 25Finland
  3. 3.Institut für Angewandte Informatik und Formale BeschreibungsverfahrenUniversität Karlsruhe (TH)KarlsruheWest-Germany

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