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Seokil Song - One of the best experts on this subject based on the ideXlab platform.
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Dynamic partition lock method to reduce Transaction Abort rates of cloud database
Cluster Computing, 2015Co-Authors: T. Kim, Seokil SongAbstract:Generally, existing cloud data management systems (CDMSs) support partition tolerance in mandatory and sacrifice consistency according to the CAP theory. Partition tolerance means that the database can be split over multiple servers to guarantee consistency or availability, even though the network is partitioned. This property is mandatory in CDMSs which consist of multiple servers. On the contrary, consistency of database is not strongly required in applications of CDMSs such as online shopping, search engine and so on. However, recently emerging applications such as online gaming, collaborative editing, and social networking require strong consistency, which requires that there be only one copy of each data item, and that only serializable access be permitted. Several approaches have been proposed to support consistency in CDMSs. These can be classified into three groups. In the first group of approaches, Transactions are processed over multiple records in only one node. In the second group, limited wider Transaction support is given to allow Transactions to run in multiple nodes with some constraints. In the third group, Transaction services are unbundled from the kernel of database management systems. In this paper, we propose a Transaction processing method for CDMSs in which snapshot isolation (SI) techniques are applied to the unbundling Transaction approach to increase its Transaction throughput. The partition locking used by the unbundling Transaction approach is static, and therefore, the number of partitions does not change, even when the number of records or the access frequency increases. This feature of the approach may increase the number of failed Transactions when a SI technique is applied to the approach. We propose a dynamic partitioning lock method to solve these problems. Our proposed method monitors the number of Transactions that access each partition and the number of records in each partition. Then, it splits any partition that is accessed more times than a particular threshold and maintains the split information using a KD-tree. The results of simulations conducted using our proposed dynamic partitioning lock methods show that less Transaction Aborts occur with our proposed method than with conventional methods.
Chun Chen - One of the best experts on this subject based on the ideXlab platform.
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reducing Transaction Abort rate of epidemic algorithm in replicated databases
International Conference on Computational Science, 2005Co-Authors: Huaizhong Lin, Zengwei Zheng, Chun ChenAbstract:Easy to deploy, robust, and highly resilient to failures, epidemic algorithms are a potentially effective mechanism for propagating information in large peer-to-peer systems deployed on Internet or ad hoc networks. In the paper, we explore the epidemic algorithms used for Transaction processing in replicated databases that reside in weakly connected environments. We concentrate on the Transaction commit voting process of the epidemic algorithms and suggest a new voting method, which takes an optimistic approach in conflict reconciliation. The optimistic voting protocol decreases Abort rate and improves average response time of Transactions.
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International Conference on Computational Science (1) - Reducing Transaction Abort rate of epidemic algorithm in replicated databases
Lecture Notes in Computer Science, 2005Co-Authors: Huaizhong Lin, Zengwei Zheng, Chun ChenAbstract:Easy to deploy, robust, and highly resilient to failures, epidemic algorithms are a potentially effective mechanism for propagating information in large peer-to-peer systems deployed on Internet or ad hoc networks. In the paper, we explore the epidemic algorithms used for Transaction processing in replicated databases that reside in weakly connected environments. We concentrate on the Transaction commit voting process of the epidemic algorithms and suggest a new voting method, which takes an optimistic approach in conflict reconciliation. The optimistic voting protocol decreases Abort rate and improves average response time of Transactions.
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ICCSA (4) - Transaction reordering for epidemic quorum in replicated databases
Computational Science and Its Applications – ICCSA 2005, 2005Co-Authors: Huaizhong Lin, Zengwei Zheng, Chun ChenAbstract:Epidemic model gives an efficient approach to Transaction processing of replication systems in weakly connected environments. The approach has the advantages of high adaptation, support for low-bandwidth network, committing updates in an entirely decentralized control fashion, and so on. Optimistic voting protocol of epidemic model, which introduces condition and order vote in the voting process of Transactions, takes an optimistic approach in conflict reconciliation. Though it brings down Transaction Abort rate dramatically when compared to other implementing protocols, optimistic voting protocol also rollbacks Transactions unnecessarily. In this paper, Transaction reordering technique is proposed in optimistic voting protocol to reduce the probability of Transaction Aborts. The protocol ensures one-copy serializability and does not lead to any deadlock situation. Experimental results suggest that the Transaction reordering technique decreases Abort rate and improves average response time of Transactions markedly.
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Optimistic voting for managing replicated data
Journal of Computer Science and Technology, 2002Co-Authors: Huaizhong Lin, Chun ChenAbstract:An epidemic model gives an efficient approach for Transaction processing of replication systems in weakly connected environments. The approach has the advantages of high adaptation, support for low-bandwidth network, and committing updates in an entirely decentralized control fashion. But the previous implementing protocols, like ROWA protocol, quorum protocol, and voting protocol, have a common shortcoming that they are pessimistic in conflict reconciliation, therefore bring high Transaction Abort rate and reduce system performance dramatically when the workload scales up. In this paper, an optimistic voting protocol, which introduces condition vote and order vote in the voting process of Transactions, is proposed. The condition vote and order vote postpone the final decision on conflicting Transactions and avoid Transaction Aborts that are incurred by read-write and write-write conflicts. Experimental results indicate that the optimistic voting protocol decreases Abort rate and improves average response time of Transactions markedly when compared to other protocols.
Hendrik Decker - One of the best experts on this subject based on the ideXlab platform.
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reducing Transaction Abort rates with prioritized atomic multicast protocols
European Conference on Parallel Processing, 2008Co-Authors: Emili Miedes, Francesc D Munozescoi, Hendrik DeckerAbstract:Priority atomic multicast is a total-order multicast message delivery service that enables applications to prioritize the sequence by which messages are delivered, while regular total order properties remain invariant. Priority-based message delivery can serve to reduce the Abortion rate of Transactions. In this study, we compare three classical total order protocols against their corresponding prioritized versions, in the framework of a replication middleware. To this end, we use a test application that broadcasts prioritized messages by these protocols, and measure the effect of the priorization. We show that, under certain conditions, the use of prioritized protocols yields lower Abort rates than the corresponding non-prioritized protocols.
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Euro-Par - Reducing Transaction Abort Rates with Prioritized Atomic Multicast Protocols
Lecture Notes in Computer Science, 2008Co-Authors: Emili Miedes, Francesc D. Muñoz-escoí, Hendrik DeckerAbstract:Priority atomic multicast is a total-order multicast message delivery service that enables applications to prioritize the sequence by which messages are delivered, while regular total order properties remain invariant. Priority-based message delivery can serve to reduce the Abortion rate of Transactions. In this study, we compare three classical total order protocols against their corresponding prioritized versions, in the framework of a replication middleware. To this end, we use a test application that broadcasts prioritized messages by these protocols, and measure the effect of the priorization. We show that, under certain conditions, the use of prioritized protocols yields lower Abort rates than the corresponding non-prioritized protocols.
Emili Miedes - One of the best experts on this subject based on the ideXlab platform.
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Improving the benefits of multicast prioritization algorithms
The Journal of Supercomputing, 2014Co-Authors: Emili Miedes, Francesc D. Muñoz-escoíAbstract:Prioritized atomic multicast consists in delivering messages in total order while ensuring that the priorities of the messages are considered; i.e., messages with higher priorities are delivered first. That service can be used in multiple applications. An example is the usage of prioritization algorithms for reducing the Transaction Abort rates in applications that use a replicated database system. To this end, Transaction messages get priorities according to their probability of violating the existing integrity constraints. This paper evaluates how that Abort reduction may be improved varying the message sending rate and the bounds set on the length of the priority reordering queue being used by those multicast algorithms.
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OTM Conferences (1) - On the Cost of Prioritized Atomic Multicast Protocols
On the Move to Meaningful Internet Systems: OTM 2009, 2009Co-Authors: Emili Miedes, Francesc D. Muñoz-escoíAbstract:A prioritized atomic multicast protocol allows an application to tag messages with a priority that expresses their urgency and tries to deliver first those with a higher priority. For instance, such a service can be used in a database replication context, to reduce the Transaction Abort rate when integrity constraints are used. We present a study of the three most important and well-known classes of atomic multicast protocols in which we evaluate the cost imposed by the prioritization mechanisms, in terms of additional latency overhead, computational cost and memory use. This study reveals that the behavior of the protocols depends on the particular properties of the setting (number of nodes, message sending rates, etc.) and that the extra work done by a prioritized protocol does not introduce any additional latency overhead in most of the evaluated settings. This study is also a performance comparison of these classes of total order protocols and can be used by system designers to choose the proper prioritized protocol for a given deployment.
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reducing Transaction Abort rates with prioritized atomic multicast protocols
European Conference on Parallel Processing, 2008Co-Authors: Emili Miedes, Francesc D Munozescoi, Hendrik DeckerAbstract:Priority atomic multicast is a total-order multicast message delivery service that enables applications to prioritize the sequence by which messages are delivered, while regular total order properties remain invariant. Priority-based message delivery can serve to reduce the Abortion rate of Transactions. In this study, we compare three classical total order protocols against their corresponding prioritized versions, in the framework of a replication middleware. To this end, we use a test application that broadcasts prioritized messages by these protocols, and measure the effect of the priorization. We show that, under certain conditions, the use of prioritized protocols yields lower Abort rates than the corresponding non-prioritized protocols.
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Euro-Par - Reducing Transaction Abort Rates with Prioritized Atomic Multicast Protocols
Lecture Notes in Computer Science, 2008Co-Authors: Emili Miedes, Francesc D. Muñoz-escoí, Hendrik DeckerAbstract:Priority atomic multicast is a total-order multicast message delivery service that enables applications to prioritize the sequence by which messages are delivered, while regular total order properties remain invariant. Priority-based message delivery can serve to reduce the Abortion rate of Transactions. In this study, we compare three classical total order protocols against their corresponding prioritized versions, in the framework of a replication middleware. To this end, we use a test application that broadcasts prioritized messages by these protocols, and measure the effect of the priorization. We show that, under certain conditions, the use of prioritized protocols yields lower Abort rates than the corresponding non-prioritized protocols.
Songseokil - One of the best experts on this subject based on the ideXlab platform.
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Dynamic partition lock method to reduce Transaction Abort rates of cloud database
Cluster Computing, 2015Co-Authors: Kimtaehwan, SongseokilAbstract:Generally, existing cloud data management systems (CDMSs) support partition tolerance in mandatory and sacrifice consistency according to the CAP theory. Partition tolerance means that the database...