Summary: The Buffer Tree:
A New Technique for Optimal I/OAlgorithms ?
Department of Computer Science, University of Aarhus, Denmark ???
Abstract. In this paper we develop a technique for transforming an in
ternal memory tree data structure into an external storage structure. We
show how the technique can be used to develop a searchtreelike struc
ture, a priorityqueue, a (onedimensional) rangetree and a segmenttree,
and give examples of how these structures can be used to develop effi
cient I/Oalgorithms. All our algorithms are either extremely simple or
straightforward generalizations of known internal memory algorithms ---
given the developed external data structures.
In the last few years, more and more attention has been given to Input/Output
(I/O) complexity of existing algorithms and to the development of new I/O
efficient algorithms. This is due to the fact that communication between fast in
ternal memory and slower external storage is the bottleneck in many largescale