Amortization results for chromatic search trees, with an application to priority queues

  • Joan Boyar
  • Rolf Fagerberg
  • Kim S. Larsen
Invited Presentation
Part of the Lecture Notes in Computer Science book series (LNCS, volume 955)


The intention in designing data structures with relaxed balance, such as chromatic search trees, is to facilitate fast updating on shared-memory asynchronous parallel architectures. To obtain this, the updating and rebalancing have been uncoupled, so extensive locking in connection with updates is avoided.

In this paper, we prove that only an amortized constant amount of rebalancing is necessary after an update in a chromatic search tree. We also prove that the amount of rebalancing done at any particular level decreases exponentially, going from the leaves towards the root. These results imply that, in principle, a linear number of processes can access the tree simultaneously.

We have included one interesting application of chromatic trees. Based on these trees, a priority queue with possibilities for a greater degree of parallelism than in previous proposals can be implemented.


Search Tree Priority Queue Binary Search Tree Weighted Height Chromatic Tree 
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 1995

Authors and Affiliations

  • Joan Boyar
    • 1
  • Rolf Fagerberg
    • 1
  • Kim S. Larsen
    • 1
  1. 1.Odense UniversityDenmark

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