## Time-Adaptive Algorithms for Synchronization (1994)

Venue: | SIAM J. Comput |

Citations: | 26 - 6 self |

### BibTeX

@INPROCEEDINGS{Alur94time-adaptivealgorithms,

author = {Rajeev Alur and Hagit Attiya and Gadi Taubenfeld},

title = {Time-Adaptive Algorithms for Synchronization},

booktitle = {SIAM J. Comput},

year = {1994},

pages = {800--809},

publisher = {ACM}

}

### Years of Citing Articles

### OpenURL

### Abstract

We consider concurrent systems in which there is an unknown upper bound on memory access time. Such a model is inherently different from asynchronous model where no such bound exists, and also from timing-based models where such a bound exists and is known a priori. The appeal of our model lies in the fact that while it abstracts from implementation details, it is a better approximation of real concurrent systems compared to the asynchronous model. Furthermore, it is stronger than the asynchronous model enabling us to design algorithms for problems that are unsolvable in the asynchronous model. Two basic synchronization problems, consensus and mutual exclusion, are investigated in a shared memory environment that supports atomic read/write registers. We show that \Theta(\Delta log \Delta log log \Delta ) is an upper and lower bound on the time complexity of consensus, where \Delta is the (unknown) upper bound on memory access time. For the mutual exclusion problem, we design an effic...

### Citations

1520 | Impossibility of distributed consensus with one faulty process - FISCHER, LYNCH, et al. - 1985 |

763 | Wait-Free Synchronization
- Herlihy
- 1991
(Show Context)
Citation Context ...time complexity of any algorithm, where fac \Gamma1 is the inverse of the factorial function. The algorithm that achieves this bound is fast in the absence of contention. Since consensus is universal =-=[He91]-=-, our results imply that atomic reads and writes are universal in the unknown-delay model. For the mutual exclusion problem, we have presented an algorithm in which, in the presence of contention, a p... |

550 | Reaching agreements in the presence of faults
- Pease, Shostak, et al.
- 1980
(Show Context)
Citation Context ...us model by investigating two basic synchronization problems, consensus and mutual exclusion. In the consensus problem, processes need to agree on a common output in the presence of possible failures =-=[PSL80]-=-. It has been proven that when even one process can fail, the consensus problem is not solvable in asynchronous systems [DDS87, FLP85, LA87]. In the known-delay model, there is an algorithm which tole... |

464 | Consensus in the presence of partial synchrony
- DWORK, LYNCH, et al.
- 1988
(Show Context)
Citation Context ...hat are unsolvable in the asynchronous model. The importance of a timing-based model with unknown bounds is also supported by an earlier work of Dwork et al. in the context of message-passing systems =-=[DLS88]-=-. We use a shared memory model where processes communicate with each other by reading and writing to shared registers. We assume that there is an upper bound, denoted by \Delta, on time required for a... |

302 |
Solution to a Problem in Concurrent Programming Control
- Dijkstra
- 1965
(Show Context)
Citation Context ...plexity by a factor of fac \Gamma1 (\Delta). The mutual exclusion problem is to design a protocol that guarantees mutually exclusive access to a critical section among a number of competing processes =-=[Dij65]-=-. A mutual exclusion algorithm satisfies the fast access property if in absence of contention a process needs to execute only a constant number of steps in order to enter or exit its critical section.... |

240 | On the minimal synchronism needed for distributed consensus - DOLEV, DWORK, et al. - 1987 |

233 | A Fast Mutual Exclusion Algorithm
- Lamport
- 1987
(Show Context)
Citation Context ...mutual exclusion algorithm satisfies the fast access property if in absence of contention a process needs to execute only a constant number of steps in order to enter or exit its critical section. In =-=[Lam87]-=-, Lamport presented a fast mutual exclusion algorithm that satisfies the fast access property. In the presence of contention, however small, the winning process in Lamport's algorithm may have to chec... |

158 | Memory Requirements for Agreement Among Unreliable Asynchronous Processes - Loui, Abu-Amara - 1987 |

133 | Fast randomized consensus using shared memory
- Aspnes, Herlihy
- 1990
(Show Context)
Citation Context ...hat each transition of the algorithm preserves OE. Thus OE is an invariant of the algorithm. The lemma follows immediately. 4 The idea of using preferences for consensus was used previously, e.g., in =-=[AH90]-=-. Shared registers: initially: out =?, y[] =?, x[; ] = 0. Local registers: initially: r i = 1, v i = in i . Constants: d r = r! for all r. 1 while out =? do 2 x[r i ; v i ] := 1; 3 if y[r i ] =? then ... |

54 | Adaptive solutions to the mutual exclusion problem - CHOY, SINGH - 1994 |

46 | Bounds on the time to reach agreement in the presence of timing uncertainty - DWORK, LYNCH, et al. - 1991 |

29 | Improving Fast Mutual Exclusion - Styer - 1992 |

24 | Timing-based Mutual Exclusion
- Lynch, Shavit
- 1992
(Show Context)
Citation Context ...ys b and trying , each of n bits, with one array of n 3-valued registers. Lynch and Shavit have proved that, when the timing bounds are not known, n is a lower bound on the number of shared registers =-=[LS92]-=-. (The model used therein for algorithm design is the known-delay model, but their lower bound proof continues to hold also for the unknown-delay model.) In contrast, the algorithms for mutual exclusi... |

22 | Early detection of message forwarding faults
- Herzberg, Kutten
(Show Context)
Citation Context ...of faulty processes (compared to the total number of processes) that can be tolerated. Our consensus algorithm is wait-free, that is, it can tolerate any number of crash failures. Herzberg and Kutten =-=[HK89]-=- have studied a message-passing model where a priori upper bound on message delivery time is known, but is much larger than the actual message delay; this encourages the use of the (unknown) message d... |

18 | scalable synchronization with minimal hardware support - Fast - 1993 |

16 | Fast Timing-based Algorithms
- Alur, Taubenfeld
- 1996
(Show Context)
Citation Context ...ensus problem is not solvable in asynchronous systems [DDS87, FLP85, LA87]. In the known-delay model, there is an algorithm which tolerates any number of failures and terminates within time O(\Delta) =-=[AT96]-=-. Our first result is a consensus algorithm that works in the unknown-delay model. The algorithm guarantees that, in every possible execution, processes never decide on conflicting values and the deci... |

13 | How to share an object: A fast timing-based solution - Alur, Taubenfeld - 1993 |

13 | Fast mutual exclusion, even with contention - Michael, Scott - 1993 |