On Conspiracies and Hyperfairness in Distributed Computing

We study the phenomenon of conspiracies, a certain class of livelocks, in distributed computations. This elementary phenomenon occurs in systems with shared variables, shared actions as well as in message-passing systems. We propose a new and simple characterization via a new notion of hyperfairness, which postulates the absence of conspiracies. We argue that hyperfairness is a useful tool for understanding some impossibility results, in particular results involving crash-tolerance. As a main result, we show that a large subclass of hyperfairness can be implemented through partial synchrony and randomization.

[1]  Nissim Francez,et al.  Fairness and hyperfairness in multi-party interactions , 2005, Distributed Computing.

[2]  K. Mani Chandy,et al.  Parallel program design - a foundation , 1988 .

[3]  Hagen Völzer.  On Randomization Versus Synchronization in Distributed Systems , 2004, ICALP.

[4]  Nissim Francez,et al.  On equivalence-completions of fairness assumptions , 2005, Formal Aspects of Computing.

[5]  Michael Ben-Or,et al.  Another advantage of free choice (Extended Abstract): Completely asynchronous agreement protocols , 1983, PODC '83.

[6]  Amir Pnueli,et al.  The Glory of the Past , 1985, Logic of Programs.

[7]  Amir Pnueli,et al.  On the extremely fair treatment of probabilistic algorithms , 1983, STOC.

[8]  Maurice Herlihy,et al.  Wait-free synchronization , 1991, TOPL.

[9]  Hagen Völzer.  A constructive proof for FLP , 2004, Inf. Process. Lett..

[10]  Robin Milner,et al.  On Observing Nondeterminism and Concurrency , 1980, ICALP.

[11]  Yat-Sang Kwong.  On the Absence of Livelocks in Parallel Programs , 1979, Semantics of Concurrent Computation.

[12]  Yuh-Jzer Joung,et al.  Two decentralized algorithms for strong interaction fairness for systems with unbounded speed variability , 2000, Theor. Comput. Sci..

[13]  Grzegorz Rozenberg.  Advances in Petri Nets 1987 , 1986, Lecture Notes in Computer Science.

[14]  Eike Best,et al.  Fairness and Conspiracies , 1984, Inf. Process. Lett..

[15]  Jerzy Tiuryn,et al.  Logics of Programs , 1991, Handbook of Theoretical Computer Science, Volume B: Formal Models and Sematics.

[16]  Leslie Lamport,et al.  Time, clocks, and the ordering of events in a distributed system , 1978, CACM.

[17]  G. Kahn,et al.  Semantics of Concurrent Computation , 1979, Lecture Notes in Computer Science.

[18]  Yuh-Jzer Joung,et al.  On Fairness Notions in Distributed Systems: II. Equivalence-Completions and Their Hierarchies , 2001, Inf. Comput..

[19]  Edsger W. Dijkstra,et al.  Hierarchical ordering of sequential processes , 1971, Acta Informatica.

[20]  Nancy A. Lynch,et al.  Consensus in the presence of partial synchrony , 1988, JACM.

[21]  Michael Ben-Or,et al.  Another advantage of free choice (Extended Abstract): Completely asynchronous agreement protocols , 1983, PODC '83.

[22]  Nancy A. Lynch,et al.  Impossibility of distributed consensus with one faulty process , 1985, JACM.

[23]  Sam Toueg,et al.  Unreliable failure detectors for reliable distributed systems , 1996, JACM.

[24]  Leslie Lamport,et al.  Fairness and hyperfairness , 2000, Distributed Computing.