Heterogeneous and Mobile Recovery

93 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2000.Traditional checkpoint intervals typically cannot control maximum recovery time for log-based checkpointing protocols and may cause unnecessary checkpointing overhead. In this thesis, an adaptive checkpointing protocol is designed to accurately enforce the user-defined recovery time and to reduce excessive checkpoints. Instead of using fixed checkpoint intervals, the adaptive protocol creates checkpoints based on the status of current execution. A receiver-based message logging algorithm has been implemented and evaluated on both wired and wireless networks. The experimental results show that the adaptive protocol incurs low overhead, avoids unnecessary checkpointing, and reduces failure-free execution time.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

PREACHES - Portable Recovery and Checkpointing in Heterogeneous Systems

Checkpointing in a homogeneous environment, where both checkpointing and recovery are performed on the same type of machine and operating system, has been studied extensively. As heterogeneous distributed systems become pervasive, it is desirable to extend the capability of checkpointing to non-homogeneous environments. This paper describes a prototype, PREACHES, that achieves portable checkpointing of single process applications in heterogeneous systems using checkpoint propagation. The checkpoint propagation technique generates machine-dependent checkpoints for each different architecture in the heterogeneous environment. When failure occurs, the failed process can be restarted on a specified machine with the checkpoint that is appropriate for the architecture. An implementation of PREACHES on a heterogeneous network of workstations has been successfully developed based on TCP/IP communication. PREACHES also provides automatic and fast recovery for single process programs. 1 Introdu..

Message Logging in Mobile Computing

Dependable mobile computing is enhanced by independent recovery, low power consumption and no dependence on stable storage at the mobile host. Existing recovery protocols proposed for mobile environments typically create consistent global checkpoints that do not guarantee independent recovery and low power consumption. This paper demonstrates the advantages of message logging by describing a receiver based logging protocol. Checkpointing is utilized to limit log size and recovery latency. We compare the performance of our approach with that of existing mobile checkpointing and recovery algorithms in terms of failure free overhead and recovery time. We also describe a stable storage management scheme for mobile support stations. Garbage collection is achieved without direct participation of mobile hosts