Lower bounds for external memory dictionaries

  • Authors:
  • Gerth Stolting Brodal;Rolf Fagerberg

  • Affiliations:
  • University of Aarhus, Ny Munkegade, DK-8000 Århus C, Denmark;University of Aarhus, Ny Munkegade, DK-8000 Århus C, Denmark

  • Venue:
  • SODA '03 Proceedings of the fourteenth annual ACM-SIAM symposium on Discrete algorithms
  • Year:
  • 2003

Quantified Score

Hi-index 0.00

Visualization

Abstract

We study trade-offs between the update time and the query time for comparison based external memory dictionaries. The main contributions of this paper are two lower bound trade offs between the I/O complexity of member queries and insertions: If N N/B I/Os, then (1) there exists a query requiring N/(M. ·~O(δ)) I/Os, and (2) there exists a query requiring Ω(logδlog2N ~ I/Os when δ is O(B/log3 N) and N is at least M2. For both lower bound we describe data structures which give matching upper bounds for a wide range of parameters, thereby showing the lower bounds to be tight within these ranges.