Encyclopedia of Database Systems

2018 Edition
| Editors: Ling Liu, M. Tamer Özsu

Tuning Concurrency Control

  • Philippe BonnetEmail author
  • Dennis Shasha
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_77


Lock tuning


Database systems implement concurrency control to give users the illusion that each transaction executes correctly, in isolation from all others. The concurrency-control algorithm in predominant use is two-phase locking. Tuning concurrency control consists in improving the performance of concurrent operations by reducing the number, duration and scope of the conflicts due to locking.

Historical Background

In 1976, Jim Gray et al. identified the fundamental concurrency control trade-off between correctness and performance. They discussed different lock granularities and introduced the notion of degrees of consistency.


Database systems attempt to give users the illusion that each transaction executes in isolation from all others. The ANSI SQL standard, for example, makes this explicit with its concept of degrees of isolation. Full isolation or serializabilityis the guarantee that each transaction that completes will appear to execute one at a...

This is a preview of subscription content, log in to check access.

Recommended Reading

  1. 1.
    Bernstein P, Hadzilacos V, Goodman N. Concurrency control and recovery in database systems. Boston: Addison-Wesley; 1987.Google Scholar
  2. 2.
    Gray J, Reuter A. Transaction processing: concepts and techniques. San Francisco: Morgan Kaufmann; 1992.zbMATHGoogle Scholar
  3. 3.
    Shasha D, Bonnet P. Database tuning: principles, experiments and troubleshooting techniques. San Francisco: Morgan Kaufmann; 2002.Google Scholar
  4. 4.
    Weikum G, Vossen G. Transactional information systems: theory, algorithms, and the practice of concurrency control and recovery. San Francisco: Morgan Kaufmann; 2001.Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Computer ScienceIT University of CopenhagenCopenhagenDenmark
  2. 2.Department of Computer ScienceNew York UniversityNew YorkUSA

Section editors and affiliations

  • Dennis Shasha
    • 1
  1. 1.Dep. of Computer ScienceNew York Univ.New YorkUSA