A nested dual ascent procedure for the dynamic single file allocation problem

In this paper the authors consider the dynamic file allocation problem, where query and update costs vary from one time period to the next. They develop a mixed integer linear program to model this problem. The present model also incorporates startup costs which are incurred if a location maintains a file copy in a given time period, but did not maintain it the previous time period. The authors develop a branch-and-bound algorithm to solve this problem optimally. The present algorithm uses a new nested dual ascent procedure to solve the dual of the LP relaxation quickly and provide good feasible solutions. The computational results show that the proposed solution procedure outperforms MPSX by many orders of magnitude and is able to solve large problems in a reasonable amount of time.