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Relaxed balance through standard rotations

  • Kim S. Larsen
  • Eljas Soisalon-Soininen
  • Peter Widmayer
Session 11B: Invited Lecture
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1272)

Abstract

We consider binary search trees, where rebalancing transformations need not be connected with updates but may be delayed. For standard AVL tree rebalancing, we prove that even though the rebalancing operations are uncoupled from updates, their total number is bounded by O(Mlog(M + N)), where M is the number of updates to an AVL tree of initial size N. Hence, relaxed balancing of AVL trees comes at no extra cost asymptotically. Furthermore, our scheme differs from most other relaxed balancing schemes in an important aspect: No rebalancing transformation can be done in the wrong direction, i.e., no performed rotation can make the tree less balanced. Moreover, each performed rotation indeed corresponds to a real imbalance situation in the tree.

Our results are important in designing efficient concurrency control strategies for main-memory databases. Main-memory search structures have gained new applications in large embedded systems, such as switching systems for mobile telephones.

Keywords

Search Tree Height Difference Active Node Mobile Telephone Switching System 
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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Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Kim S. Larsen
    • 1
  • Eljas Soisalon-Soininen
    • 2
  • Peter Widmayer
    • 3
  1. 1.Department of Mathematics and Computer ScienceOdense UniversityOdense MDenmark
  2. 2.Laboratory of Information Processing ScienceHelsinki University of TechnologyEspooFinland
  3. 3.Institut für Theoretische InformatikETH ZentrumZurichSwitzerland

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