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Using shared virtual memory for parallel join processing

Ambuj Shatdal, Jeffrey F. Naughton
1993 Proceedings of the 1993 ACM SIGMOD international conference on Management of data - SIGMOD '93  
The implementation of the algorithm requires few modifications to existing shared-nothing parallel database systems.  ...  in the presence of skew than previously proposed parallel join processing algorithms.  ...  Acknowledgment The idea of looking at shared virtual memory for join processing was originally suggested to us by David De-Witt, We also thank the numerous writers of the original Gamma simulator without  ... 
doi:10.1145/170035.170062 dblp:conf/sigmod/ShatdalN93 fatcat:hgx2arj35rabzfmkavbef535zi

Using shared virtual memory for parallel join processing

Ambuj Shatdal, Jeffrey F. Naughton
1993 SIGMOD record  
The implementation of the algorithm requires few modifications to existing shared-nothing parallel database systems.  ...  in the presence of skew than previously proposed parallel join processing algorithms.  ...  Acknowledgment The idea of looking at shared virtual memory for join processing was originally suggested to us by David De-Witt, We also thank the numerous writers of the original Gamma simulator without  ... 
doi:10.1145/170036.170062 fatcat:3mz7exov4jbjnlcq55mkoyct4i

Efficient outer join data skew handling in parallel DBMS

Yu Xu, Pekka Kostamaa
2009 Proceedings of the VLDB Endowment  
Although extensive research has been done on handling skewed processing for inner joins in PDBMS, there is no known research on data skew handling for parallel outer joins.  ...  Business intelligence tools used by enterprises frequently generate a large number of outer joins and require high performance from the underlying database systems.  ...  In principle, prior algorithms in the second category can be adapted to handle the outer join skew problem because they can handle skewed processing dynamically.  ... 
doi:10.14778/1687553.1687565 fatcat:g4q2bmafhjbzvlfrb2d2mqulxu

Parallel database systems

David J. DeWitt, Jim Gray
1990 SIGMOD record  
Parallel database machine architectures based on exotic hardware have evolved to a parallel database systems running atop a parallel dataflow software architecture based on conventional shared-nothing  ...  These new designs provide speedup and scaleup when processing relational database queries. This paper reviews the techniques used by such systems, and surveys current commercial and research systems.  ...  database reorganization, and algorithms for handling relations with highly skewed data distributions.  ... 
doi:10.1145/122058.122071 fatcat:4mjtunvs2bav5c27z2jjdeu4zy

Handling data skew in parallel joins in shared-nothing systems

Yu Xu, Pekka Kostamaa, Xin Zhou, Liang Chen
2008 Proceedings of the 2008 ACM SIGMOD international conference on Management of data - SIGMOD '08  
of data skew in a shared-nothing system.  ...  Shared nothing parallel database management systems [16] can scale up "horizontally" by adding more nodes. Most parallel algorithms, however, do not take into account data skew.  ...  Conventionally, in a shared nothing parallel system, there are two join geographies to evaluate R R.a=S.b 1 S.  ... 
doi:10.1145/1376616.1376720 dblp:conf/sigmod/XuKZC08 fatcat:npg2gpilk5cdpdi2jswh2aqxqa

Query Load Balancing in Parallel Database Systems [chapter]

Luc Bouganim
2017 Encyclopedia of Database Systems  
We consider the execution of multi-join queries in a hierarchical parallel system, i.e., a shared-nothing system whose nodes are shared-memory multiprocessors.  ...  In this paper, we propose a dynamic execution model that maximizes local load balancing within shared-memory nodes and minimizes the need for load sharing across nodes.  ...  Acknowledgments The authors wish to thank Benoit Dageville for many fruitful discussions on parallel execution model and Jean-Paul Chieze for helping us with the KSR1 at Inria.  ... 
doi:10.1007/978-1-4899-7993-3_1080-2 fatcat:5zr45zzzwzgcnfgwxgc4ahpdhi

Considering data skew factor in multi-way join query optimization for parallel execution

Kien A. Hua, Yo-Lung Lo, Honesty C. Young
1993 The VLDB journal  
A consensus on parallel architecture for very large database management has emerged. This architecture is based on a shared-nothing hardware organization.  ...  In this article we propose a dynamic load balancing technique for multi-way joins, and investigate the effect of load balancing on query optimization.  ...  Furthermore, in this article, we introduce data skew as a new factor for query optimization. We will show that load balancing is more difficult for a shared-nothing system with many PNs.  ... 
doi:10.1007/bf01228673 fatcat:wuo6quy7qnda7ljl2exovdr3sa

Skew handling in the DBS3 parallel database system [chapter]

Luc Bouganim, Daniela Florescu, Benoît Dageville
1996 Lecture Notes in Computer Science  
In this paper, we present a solution which reduces these limitations in DBS3, a shared-memory parallel database system.  ...  To address the problem of load balancing in the presence of data skew, we analyze three important factors that influence the behavior of our parallel execution model: skew factor, degree of parallelism  ...  Acknowledgments: The authors thank Patrick Valduriez for his assistance in the preparation of this paper and Michael Franklin for his careful reading. They also want to thank J.P. Chieze and A.  ... 
doi:10.1007/3-540-61695-0_9 fatcat:vr3s6ptrczbpbdpmpth3hmswnm

Skew-Aware Join Optimization for Array Databases

Jennie Duggan, Olga Papaemmanouil, Leilani Battle, Michael Stonebraker
2015 Proceedings of the 2015 ACM SIGMOD International Conference on Management of Data - SIGMOD '15  
This further complicates the planning of array joins. In this paper, we introduce a join optimization framework that is skew-aware for distributed joins. This optimization consists of two phases.  ...  Although some of it can be processed in a relational database, much of it is better suited to array-based engines. As such, it is important to optimize the query processing of these systems.  ...  ACKNOWLEDGMENTS We thank the anonymous reviewers for their helpful feedback. This research was funded by the Intel Science and Technology Center for Big Data and by NSF IIS 1253196.  ... 
doi:10.1145/2723372.2723709 dblp:conf/sigmod/DugganPBS15 fatcat:ez3jrfqbcjfqvhn6boq2vnycya

Compiled Plans for In-Memory Path-Counting Queries [chapter]

Brandon Myers, Jeremy Hyrkas, Daniel Halperin, Bill Howe
2015 Lecture Notes in Computer Science  
We compile Datalog queries into main-memory pipelined hash-join plans in C++, and show that the resulting programs easily outperform PostgreSQL on real graphs with different degrees of skew.  ...  Grappa is a good target for building a parallel query system as its shared memory programming model and communication mechanisms provide productivity and performance when building communication-intensive  ...  Query execution code for Grappa is simple, being symmetric in structure to sequential C++.  ... 
doi:10.1007/978-3-319-13960-9_3 fatcat:irr2plv7rrgyba6pehlaqyuqhe

Model and procedure for performance and availability-wise parallel warehouses

Pedro Furtado
2009 Distributed and parallel databases  
In such a scenario, care must be taken for handling processing heterogeneity and availability, so we study and propose efficient solutions for this.  ...  Consider data warehouses as large data repositories queried for analysis and data mining in a variety of application contexts.  ...  For the actual experiments we used a DWPA [7] parallel database middleware prototype developed in our research lab and targeted at share-nothing environments.  ... 
doi:10.1007/s10619-009-7038-7 fatcat:xibt4s7ernfffdsfaiavsntc6m

Processing multi-join query in parallel systems

Kian-Lee Tan, Hongjun Lu
1992 Proceedings of the 1992 ACM/SIGAPP Symposium on Applied computing technological challenges of the 1990's - SAC '92  
In parallel systems, a number of joins from one or more queries ean be exeeuted either seriatly or in parallel.  ...  However, data skew may result in load imbalance among processors executing the same join and some clusters may be overloaded with time-consuming joins.  ...  Each relation is horizontally partitioned across the disks in the system. In [1] , it is shown that SD system performs as well as a shared nothing (SN) system.  ... 
doi:10.1145/143559.143653 dblp:conf/sac/TanL92 fatcat:wu5ldbg2njcmxbgvdlomjq2kde

An Optimal Skew-insensitive Join and Multi-join Algorithm for Distributed Architectures [chapter]

Mostafa Bamha
2005 Lecture Notes in Computer Science  
The development of scalable parallel database systems requires the design of efficient algorithms for the join operation which is the most frequent and expensive operation in relational database systems  ...  Its tradeoff between balancing overhead and speedup is analyzed using the BSP cost model which predicts a negligible join product skew and a linear speed-up.  ...  The algorithm Osfa join is proved to have an optimal complexity even in the presence of highly skewed data. Its predictably low join product skew makes it suitable for multi-join operations.  ... 
doi:10.1007/11546924_60 fatcat:xl6ra7f5xzco5igz6iqw273hoe

Data placement in shared-nothing parallel database systems

Manish Mehta, David J. DeWitt
1997 The VLDB journal  
Data placement in shared-nothing database systems has been studied extensively in the past and various placement algorithms have been proposed.  ...  This paper presents the first comprehensive simulation study of data placement issues in a shared-nothing system.  ...  The authors would like to thank Kurt Brown for helpful comments on an earlier draft of this paper.  ... 
doi:10.1007/s007780050033 fatcat:i43qujdovzec7psshfrjrocory

F1 query

Bart Samwel, Himani Apte, Felix Weigel, David Wilhite, Jiacheng Yang, Jun Xu, Jiexing Li, Zhan Yuan, Craig Chasseur, Qiang Zeng, Ian Rae, John Cieslewicz (+24 others)
2018 Proceedings of the VLDB Endowment  
Evolved out of F1, the distributed database originally built to manage Google's advertising data, F1 Query has been in production for multiple years at Google and serves the querying needs of a large number  ...  of users and systems.  ...  Finally, thank you to to the F1 SRE team for amazing F1 Query production support and help in scaling the service to 1000s of users.  ... 
doi:10.14778/3229863.3229871 fatcat:ttatl6drrrg4tex2ol6grsaqqa
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