Rectifying Orphan Components using Group-Failover in Distributed Real-time and Embedded Systems.∗

Abstract

Orphan requests are a significant problem for multi-tier dis-tributed systems since they adversely impact system cor-rectness by violating the exactly-once semantics of applica-tions and may waste resources. Orphan requests stem from the failure(s) of non-deterministic components involved in nested invocations of replicated components. Resolving this problem in the context of resource constrained, component-based, distributed real-time and embedded (DRE) systems that form end-to-end task chains is challenging because con-ventional transaction-based solutions cannot assure real-time properties of the DRE applications. To address these chal-lenges, this paper presents a group-failover protocol that comprises three key capabilities: real-time failure detection and client failover, timely mitigation of orphan requests, and two novel application state consistency strategies to ensure the correctness of DRE systems by maintaining the exactly-once semantics even during failures. Our solution is im-plemented in the context of the CIAO real-time CORBA Component Model middleware. Empirical evaluations of the group-failover protocol in both fault-free and failure recovery scenarios for DRE task chains of different sizes demonstrates a low overhead and predictable performance

Similar works

This paper was published in CiteSeerX.

Having an issue?

Is data on this page outdated, violates copyrights or anything else? Report the problem now and we will take corresponding actions after reviewing your request.