Vassos Hadzilacos

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Concurrencey Control and Recovery in Database Systems. P.A. Bernstein. Copyright 1987, Addison-Wesley, Reading. Hardcover in fine condition. Binding is secure, cover and spine are clean with minimal Finally I can be normally changed, only by any transaction must. Ss2pl or not co is, an intentional abort. In such as a well follows the following rules and has(More)
We determine what information about failures is necessary and sufficient to solve Consensus in asynchronous distributed systems subject to crash failures. In Chandra and Toueg [1996], it is shown that <italic>W</italic>, a failure detector that provides surprisingly little information about which processes have crashed, is sufficient to solve Consensus in(More)
Group mutual exclusion is a natural problem, formulated by Joung in 1998, that generalises the classical mutual exclusion problem. In group mutual exclusion a process requests a &#8220;session&#8221; before entering its critical section; processes are allowed to be in the critical section simultaneously provided they have requested the same session. To rule(More)
Chandra and Toueg proposed a new approach to overcome the impossibility of reaching consensus in asynchronous message-passing systems subject to crash failures 6]. They augment the asynchronous message-passing system with a (possibly unreliable) failure detector. Informally , a failure detector provides some information about the processes that have crashed(More)
We determine the weakest failure detectors to solve several fundamental problems in distributed message-passing systems, for <i>all</i> environments -- i.e., regardless of the number and timing of crashes. The problems that we consider are: implementing an atomic register, solving consensus, solving quittable consensus (a variant of consensus in which(More)
Serializability is the traditionally accepted notion of correctness in most database systems. However, in a multidatabase system (MDBS) environment consisting of pre-existing and autonomous database systems, requiring schedules to be serializable could severely hurt performance. Besides, in a number of instances, the semantics of transactions can be(More)