Harmonic block windows scheduling through harmonic windows scheduling

  • Authors:
  • Yi Sun;Tsunehiko Kameda

  • Affiliations:
  • School of Computing Science, Simon Fraser University, Burnaby, B.C., Canada;School of Computing Science, Simon Fraser University, Burnaby, B.C., Canada

  • Venue:
  • MIS'05 Proceedings of the 11th international conference on Advances in Multimedia Information Systems
  • Year:
  • 2005

Quantified Score

Hi-index 0.00

Visualization

Abstract

In Harmonic windows scheduling (HWS), a data file is divided into N pages and the pages are scheduled in c channels in such a way that each page i appears at least once in some channel in every window of size i. The optimal HWS problem aims to maximize N. Let κ be the largest integer satisfying Hκ ≤ c, where Hn is the nth harmonic number. Then κ is an upper bound on N, if the HWS framework is used. Thus an optimal HWS schedule wastes “bandwidth” at least c–Hκ. Harmonic block windows scheduling (HBWS) generalizes HWS by grouping b consecutive pages into a superpage. Let N be the total number of pages scheduled. The ratio N/b is directly proportional to the maximum initial waiting time in Media-on-Demand applications. We propose a method that starts with a HWS schedule and modifies it to generate a HBWS schedule that achieves a higher ratio N/b. For up to five channels, we demonstrate that we can always achieve N/b κ. We also prove that as we increase b, N/b approaches the theoretical upper bound.