Asynchronous Failure Detectors
Name
MIT-CSAIL-TR-2013-025.pdf
Size
545.7 KB
Format
Adobe PDF
Checksum (MD5)
6b653c262d9598d5997231260fcdc008
Download all files submitted through automated deposit
Author(s)
Cornejo, Alejandro
Lynch, Nancy A.
Sastry, Srikanth
Advisor(s)
Nancy Lynch
Date Issued
October 10, 2013
Series/Report no.
MIT-CSAIL-TR-2013-025
Abstract
Failure detectors -- oracles that provide information about process crashes -- are an important abstraction for crash tolerance in distributed systems. The generality of failure-detector theory, while providing great expressiveness, poses significant challenges in developing a robust hierarchy of failure detectors. We address some of these challenges by proposing (1) a variant of failure detectors called asynchronous failure detectors and (2) an associated modeling framework. Unlike the traditional failure-detector framework, our framework eschews real-time completely. We show that asynchronous failure detectors are sufficiently expressive to include several popular failure detectors including, but not limited to, the canonical Chandra-Toueg failure detectors, Sigma and other quorum failure detectors, Omega, anti-Omega, Omega^k, and Psi_k. Additionally, asynchronous failure detectors satisfy many desirable properties: they are self-implementable, guarantee that stronger asynchronous failure-detectors solve harder problems, and ensure that their outputs encode no information other than the set of crashed processes. We introduce the notion of a failure detector being representative for a problem to capture the idea that some problems encode the same information about process crashes as their weakest failure detectors do. We show that a large class of problems, called bounded problems, do not have representative failure detectors. Finally, we use the asynchronous failure-detector framework to show how sufficiently strong AFDs circumvent the impossibility of consensus in asynchronous systems.
Description
This report supersedes MIT-CSAIL-TR-2013-002.
Persistent DSpace Link
