 
Summary: LowContention Data Structures$
James Aspnesa,1, David Eisenstat2, Yitong Yinb,3,
a
Department of Computer Science, Yale University, New Haven, CT 06511, USA.
b
State Key Laboratory for Novel Software Technology, Nanjing University, Nanjing
210093, China.
Abstract
We consider the problem of minimizing contention in static (readonly) dic
tionary data structures, where contention is measured with respect to a fixed
query distribution by the maximum expected number of probes to any given
cell. The query distribution is known by the algorithm that constructs the
data structure but not by the algorithm that queries it. Assume that the
dictionary has n items. When all queries in the dictionary are equiproba
ble, and all queries not in the dictionary are equiprobable, we show how to
construct a data structure in O(n) space where queries require O(1) probes
and the contention is O(1/n). Asymptotically, all of these quantities are
optimal. For arbitrary query distributions, we construct a data structure
in O(n) space where each query requires O(log n/ log log n) probes and the
contention is O(log n/(n log log n)). The lack of knowledge of the query
