Y. Breitbart and H. F. Korth. Replication and Consistency: Being Lazy Helps Sometimes. In Proc. of the 16th ACM Symposium on Principles of Database Systems, pp. 173-- 184, 1997.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....Optimizations. 1 Introduction The replicated data management in distributed databases is a classic problem with great practical importance. Distributed data warehouses and data marts contain a huge amount of replicated data distributed among a number of sites. Therefore, in recent developments [3, 4, 6, 10] of the area there is always a trade o# among system e#ciency, data availability, data freshness, and data consistency. Two replicated data management methods are available in the literature: eager and lazy. Eager replication management gives the data consistency and the highest data freshness. ....

Y. Breitbart and H. F. Korth, Replication and Consistency: Being lazy helps sometimes, Proceedings of the ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, Tucson, Arizona, 1997.

....all but one block contain exactly B nodes increases the blocknumber by at most 2. 1. INTRODUCTION Data replication allows better performance with increased availability of data. In static environments, data replication does not have to deal with maintaining consistency among multiple copies [1, 3, 6, 11, 13, 14]. Static environments dealing with large data sets arise frequently. They include environments in which updates happen at certain, chosen points in time and in bulk, and queries are not present at the time of updating. In this paper we show how to e ectively use data replication to improve ....

Y. Breitbart and H. Korth. Replication and consistency: being lazy helps sometimes. In Proc. of 16-th ACM Symp. on Principles of Database Systems, pages 173-184, 1997.

....intensive and is therefore impractical when clients can be unreachable for long periods of time e.g. if a mobile client powers down in order to save energy. In response, researchers have proposed replicating data among multiple clients and allowing them to operate on the replicas independently [1]. This allows quicker response time, reduces the possibility of deadlock, reduces the need for energy consuming communication with the server, and allows mobility resistant to network outages, with the downside of relaxing the ACID properties [3] To aid such functionality, the architecture must ....

Y. Breitbart and H. F. Korth. Replication and consistency: Being lazy helps sometimes. Proceedings of the ACM SIGMOD Principles of Database Systems, 1997.

....to effectively and concurrently run updates to these data, even during disconnections. For example, the schedule plan of a manager may need to be updated concurrently by his secretary in the office and himself being overseas. 2] 3] and [4] attempted to solve this problem on file systems, while [1] and [6] on database systems. However, rollback of the transactions frequently happens as conflicts may occur among them, resulting in heavy workload. In [5] a strategy is proposed to partition the data value to different sites for data items which are partitionable and in which transactions ....

Breitbar, Y. and Korth, H. F.: Replication and Consistency: Being Lazy Helps Sometimes, Proc. of 16th ACM SIGACTSIGMOD -SIGART Symposium on PODS, pp. 173--184 (1997).

....evaluator of di#erent strategies, a test for the capabilities of middle ware tools and a provider of basic Grid functionalities. Di#erent replication policies and protocols are supported that range from very stringent synchronous to rather relaxed asychnronous models in terms of data consistency [9, 10]. 2 Architecture The GDMP software consists of several modules that closely work together but are easily replaceable. In this section we describe the modules and the software architecture of GDMP. The core modules are Control Communication, Request Manager, Security, Database Manager and the ....

Yuri Breitbart and Henry Korth, Replication and Consistency: Being Lazy Helps Sometimes, Proc. 16 ACM Sigact/Sigmod Symposium on the Principles of Database Systems, Tucson, AZ, 1997.

....Optimizations. 1 Introduction The replicated data management in distributed databases is a classic problem with great practical importance. Distributed data warehouses and data marts contain a huge amount of replicated data distributed among a number of sites. Therefore, in recent developments [3, 4, 6, 10] of the area there is always a trade o among system eciency, data availability, data freshness, and data consistency. Two replicated data management methods are available in the literature: eager and lazy. Eager replication management gives the data consistency and the highest data freshness. ....

Y. Breitbart and H. F. Korth, Replication and Consistency: Being lazy helps sometimes, Proceedings of the ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, Tucson, Arizona, 1997.

....high throughput rather than a high performance system which just serves a single user per time. High throughput requires several factors to be considered and optimised. In the database community, replication research mostly deals with update synchronisation of synchronous or asynchronous replicas [1, 4, 6, 7, 15, 21]. Read or write transactions are normally rather small and hence a small transfer of data is done over the network. 20] proposes a performance model for telecommunication applications which have the previously stated features regarding transactions. The main assertion is that a fully replicated ....

Y. Breitbart, H. Korth. Replication and Consistency: Being Lazy Helps Sometimes, In Proc. 16 ACM Sigact/Sigmod Symposium on the Principles of Database Systems, Tucson 1997.

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Y. Breitbart and H. F. Korth. Replication and Consistency: Being Lazy Helps Sometimes. In Proc. of the 16th ACM Symposium on Principles of Database Systems, pp. 173-- 184, 1997.

.... the system should be expanded with an additional server have been described in [9, 50] Algorithms that dynamically determine near optimal placement of replicated resources within a network have been studied in [5, 51] Finally, algorithms for replica consistency maintenance have been described in [25, 45, 8]. However, in order to apply them to the Web these algorithms need to be extended with new performance metrics as well as take into account the hierarchical structure of the Internet. Study of such algorithms exceeds the scope of this paper. 5 Replica Selection The performance improvement ....

Y. Breitbart and H. F. Korth. Replication and consistency: Being lazy helps sometimes. In Proceeding of the 16th ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, 1997.

.... the system should be expanded with an additional server have been described in [9, 42] Algorithms that dynamically determine near optimal placement of replicated resources within a network have been studied in [5, 43] Finally, algorithms for replica consistency maintenance have been described in [24, 40, 8]. However, in order to apply them to the Web these algorithms need to be extended with new performance metrics as well as take into account the hierarchical structure of the Internet. Study of such algorithms exceeds the scope of this paper. 6 Performance Analysis In Section 1 we identified two ....

....M. McCahill. Uniform resource locators (URL) IETF Network Working Group, RFC 1738, 1994. 7] A. Bestavros. Demand based reource allocation to reduce traffic and balance load in distributed information systems. In Proceeding of the 7th IEEE Symposium on Parallel and Distributed Processing, 1995. [8] Y. Breitbart and H. F. Korth. Replication and consistency: Being lazy helps sometimes. In Proceeding of the 16th ACM SIGACT SIGMOD SIGART Symposium on Principles of Database Systems, 1997. 9] Y. Breitbart, R. Vingralek, and G. Weikum. Load control in scalable distributed file structures. ....

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Y. Breitbart and H. F. Korth. Replication and consistency: Being lazy helps sometimes. In Proceeding of the 16th ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, 1997.

....study for three recently introduced protocols that guarantee global serializability and transaction atomicity without resorting to the two phase commit protocol. The protocols analyzed in this paper include a global locking protocol [10] a pessimistic protocol based on a replication graph [5], and an optimistic protocol based on a replication graph [7] The results of the study show a wide range of practical applicability for the lazy replica update approach employed in these protocols. We show that under reasonable contention conditions and sufficiently high transaction rate, both ....

....update propagation can eliminate these deficiencies. Recently, much attention has been directed towards the lazy approach to replica update propagation. The lazy approach requires that installation of updates to replicas occur only after the update transaction has committed at the origination site [8, 10, 13, 16, 17, 5, 1]. Propagation is performed by independent subtransactions spawned only after the transaction at the origination site has committed. Clearly, the activities of these subtransactions must be managed carefully to ensure global consistency and transaction atomicity. In [8] the authors introduced the ....

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Y. Breitbart and H. F. Korth. Replication and consistency: Being lazy helps sometimes. In Proceedings of the Sixteenth ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, Tucson, Arizona, May 1997.

....to eliminate all requirements on data placement. The extension is a hybrid protocol that propagates as many updates as possible in a lazy fashion. Before discussing our specific contributions in more detail, we present the system model adopted in this paper and prior work from [CRR96, GHOS96, BK97, ABKW98] 1.1 System Model The model we adopt in this paper is very similar to one from [CRR96, BK97] For each data item, a particular site is chosen as its primary site. The copy of a data item at the primary site is called the primary copy and the other copies are referred to as secondary ....

....as many updates as possible in a lazy fashion. Before discussing our specific contributions in more detail, we present the system model adopted in this paper and prior work from [CRR96, GHOS96, BK97, ABKW98] 1. 1 System Model The model we adopt in this paper is very similar to one from [CRR96, BK97] For each data item, a particular site is chosen as its primary site. The copy of a data item at the primary site is called the primary copy and the other copies are referred to as secondary copies or replicas. Each transaction originates at a single site and is a sequence of read and write ....

[Article contains additional citation context not shown here]

Yuri Breitbart and Henry F. Korth. Replication and consistency: Being lazy helps sometimes. In Proceedings of the ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, Tucson, Arizona, 1997. 24

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Y. Breitbart and H. F. Korth. Replication and consistency: being lazy helps sometimes. In Proceedings of the Sixteenth ACM SIG-SIGMOD-SIGART Symposium on Principles of Database Systems, pages 173-184, May 1997.

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Y. Breitbart, H. Korth, "Replication and Consistency: Being Lazy Helps Sometimes," presented at 16th ACM SIGACT/SIGMOD Symposium on the Principles of Database Systems, Tucson, AZ, 1997.

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Breitbart, Y., Korth, H.F.: Replication and consistency: being lazy helps sometimes. In: Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of Database Systems, ACM Press (1997) 173--184

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Yuri Breitbart and Henry F. Korth. Replication and consistency: being lazy helps sometimes. In Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of Database Systems, pages 173-- 184. ACM Press, 1997.

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Yuri Breitbart and Henry F. Korth. Replication and consistency: being lazy helps sometimes. In Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of Database Systems, pages 173--184. ACM Press, 1997.

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Breitbart, Y., Korth, H.F.: Replication and consistency: being lazy helps sometimes. In: Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of Database Systems, ACM Press (1997) 173--184

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Yuri Breitbart and Henry F. Korth. Replication and consistency: being lazy helps sometimes. In Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of Database Systems, pages 173--184. ACM Press, 1997.

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Y. Breitbart and H. F. Korth. Replication and consistency: being lazy helps sometimes. In Proceedings of the Sixteenth ACM SIG-SIGMOD-SIGART Symposium on Principles of Database Systems, pages 173-184, May 1997.

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Y. Breitbart and H. F. Korth. Replication and consistency: being lazy helps sometimes. In Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems, pages 173--184. ACM Press, 1997.

No context found.

Breitbart, Y. and H. Korth. Replication and Consistency: Being Lazy Helps Sometimes. in 16th ACM Sigact/Sigmod Symposium on the Principles of Database Systems. 1997. Tucson, AZ.

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Breitbart, Y. and H. Korth. Replication and Consistency: Being Lazy Helps Sometimes. in 16th ACM Sigact/Sigmod Symposium on the Principles of Database Systems. 1997. Tucson, AZ.

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Yuri Breitbart, Henry Korth. Replication and Consistency: Being Lazy Helps Sometimes, 16th ACM SIGACT-SIGMODSIGART Symposium on Principles of Database Systems, Tucson, Arizona, May 12-14, 1997.

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Y. Breitbart and H. F. Korth, "Replication and Consistency: Being Lazy Helps Sometimes," in Proc. of the Symposium on Principles of Database Systems, Tucson, Arizona, May 1997.

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