Movement-based checkpointing and logging for recovery in mobile computing systems

Abstract

In this paper, we present an efficient failure recovery scheme for mobile applications based on movement-based checkpointing and logging. Current approaches take checkpoints periodically without regard to the mobility rate of the user. Our movement-based checkpointing scheme takes a checkpoint only after a threshold of mobility handoffs has been exceeded. The optimal threshold is governed by the failure rate, log arrival rate, and the mobility rate of the application and the mobile host. This allows the tuning of the checkpointing rate on a per application and per mobile host basis. We identify the optimal movement threshold which will minimize the recovery cost per failure as a function of the mobile node's mobility rate, failure rate and log arrival rate. We also calculate the recoverability, i.e., the probability that the recovery can be done by a specified recovery time, and discuss the applicability of the approach.