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Parallel Query Processing Algorithms for Semi-structured Data [chapter]

Wenjun Sun, Kevin Lü
2002 Lecture Notes in Computer Science  
In this paper two types of parallel path-based query processing methods are introduced for improving the system performance.  ...  Query costs on semi-structured data could be very high due to the sequential processing of path matching in a graph shape data structure.  ...  Parallel Top-Down Query Processing Strategy (PTDQ) The top-down strategy is a natural way for evaluating a path expression.  ... 
doi:10.1007/3-540-47961-9_64 fatcat:nagg2psmzfev5djh7onnkgwa54

A Query Language for Workflow Instance Data [chapter]

Philipp Baumgärtel, Johannes Tenschert, Richard Lenz
2014 Advances in Intelligent Systems and Computing  
We present a heuristic algorithm for efficient query processing. Finally, we evaluate the performance of our query processing algorithm and compare it to SPARQL.  ...  For example, to optimize the clinical pathways of patients with stroke we need the time and associated costs of each step in the clinical pathway.  ...  This project is supported by the German Federal Ministry of Education and Research (BMBF), project grant No. 13EX1013B.  ... 
doi:10.1007/978-3-319-01863-8_9 fatcat:vzoyufl4t5fqlagdi3u4uekw4i

Parallelizing user-defined aggregations using symbolic execution

Veselin Raychev, Madanlal Musuvathi, Todd Mytkowicz
2015 Proceedings of the 25th Symposium on Operating Systems Principles - SOSP '15  
User-defined aggregations (UDAs) are integral to large-scale data-processing systems, such as MapReduce and Hadoop, because they let programmers express application-specific aggregation logic.  ...  Evaluation on both Amazon's Elastic cloud and a private 380-node Hadoop cluster housing terabytes of data demonstrates that SYMPLE reduces network communication up to several orders of magnitude and job  ...  As such, for these queries, SymPreds provide powerful expressiveness without exponential path blowups. All the queries we evaluate in this paper use a window of size one.  ... 
doi:10.1145/2815400.2815418 dblp:conf/sosp/RaychevMM15 fatcat:imldlqbetzdxzcdintyobcck4m

A Case for Stale Synchronous Distributed Model for Declarative Recursive Computation

2019 Theory and Practice of Logic Programming  
AbstractA large class of traditional graph and data mining algorithms can be concisely expressed in Datalog, and other Logic-based languages, once aggregates are allowed in recursion.  ...  Therefore, $\[{\cal P}\]$ reM can be assimilated into the data-parallel computation plans of different distributed systems, irrespective of whether these follow bulk synchronous parallel (BSP) or asynchronous  ...  A coordinator marks the completion of the overall evaluation process by individually tracking the termination of each of the worker's task.  ... 
doi:10.1017/s1471068419000358 fatcat:26z4xlqd6bfs7mmovnjvhioefa

Hardware based scalable path computation engine for multilayer traffic engineering in GMPLS networks

Sho Shimizu, Taku Kihara, Yutaka Arakawa, Naoaki Yamanaka, Kosuke Shiba
2008 2008 34th European Conference on Optical Communication  
A parallel data-flow hardware based path computation engine that makes multilayer traffic engineering more scalable is proposed.  ...  The engine achieves 100 times faster than conventional path computation scheme.  ...  In this paper, we propose a new path computation architecture that takes advantage of data-flwo type parallel processing of dynamically reconfigurable processors.  ... 
doi:10.1109/ecoc.2008.4729415 fatcat:unflyk7oijdepmohhy7nlsncqe

Aggressive Aggregation: a New Paradigm for Program Optimization [article]

Frederik Gossen, Marc Jasper, Alnis Murtovi, Bernhard Steffen
2019 arXiv   pre-print
parallel assignment that refers to an Expression DAG (ED) which realizes redundancy-free computation.  ...  ., on a partial evaluation-based decomposition of acyclic program fragments into a pair of computationally optimal structures: an Algebraic Decision Diagram (ADD) to capture conditional branching and a  ...  Here, we utilize our ED (Sec. 3.4) and therefore evaluate the sub-DAG of this ED whose root is the evaluated expression.  ... 
arXiv:1912.11281v1 fatcat:ykmqljfsbzhlvnbyvhfsm4vene

Interactive testing tool for parallel programs [chapter]

H. Krawczyk, B. Wiszniewski
1996 IFIP Advances in Information and Communication Technology  
The paper presents a model for structural testing of parallel software defmed as a graph consisting of interconnected node objects and a tool STEPS implementing it.  ...  The number of test cases required by STEPS is much lower than with the use of traditional flow-graph representations.  ...  At each entry of such a node incoming token causes the evaluation of the respective expressions (predicates).  ... 
doi:10.1007/978-0-387-34984-8_9 fatcat:twjwaa7gxnatnchf2atxgscouu

Apache VXQuery: A Scalable XQuery Implementation [article]

E. Preston Carman Jr. , Michael J. Carey Oracle Labs
2015 arXiv   pre-print
We describe the architecture of Apache VXQuery, its integration with Hyracks and Algebricks, and the XQuery optimization rules applied to the query plan to improve path expression efficiency and to enable  ...  An experimental evaluation using a real 500GB dataset with various selection, aggregation and join XML queries shows that Apache VXQuery performs well both in terms of scale-up and speed-up.  ...  Parallel Rewrite Rules After the path expression rewrite rules are applied, the plan is further optimized for parallel XQuery processing.  ... 
arXiv:1504.00331v1 fatcat:56dwi5tjbrczvn6blcupargzuy

Axiomatic-like performance analysis (ALPA)

S. Adari, R.A. Ammar
1993 Computers and Mathematics with Applications  
A given program can be mapped into these nodes and related axioms can be applied to the nodes to identify alternative flow paths in the program.  ...  A triplet of the form O{Q)q ( similar to that of Hoare's triplet [l]) is used to establish flow in program Q, with computing powers of 8 for input, and q for output.  ...  Assuming that the parallel paths in this program are perfectly parallel, we can evaluate this program by the direct application of node equations developed before.  ... 
doi:10.1016/0898-1221(93)90026-r fatcat:vojad6jwnff2voywwtlhihn5zu

Parallel performance evaluation through critical path analysis [chapter]

Benno J. Overeinder, Peter M. A. Sloot
1995 Lecture Notes in Computer Science  
In this paper we discuss the concept of space-time diagrams as a representation of the execution of an application, and then give a method, based on critical path analysis, for calculating nontrivial upper  ...  bounds on the potential parallelism, known as the average parallelism, a complement to the speedup and efficiency.  ...  Conclusions Critical path analysis is shown to be a very useful tool in performance evaluation of parallel systems.  ... 
doi:10.1007/bfb0046692 fatcat:eacvc73obvdtfdcpwbzi7obhyu

Page 60 of Journal of Research and Practice in Information Technology Vol. 27, Issue 2 [page]

1995 Journal of Research and Practice in Information Technology  
.: (1992c): Computation list evaluation and its applications, Parallel Processing Letters, 2:321-329.  ...  BRENT, R.P. (1974): The parallel evaluation of general expressions, J. ACM, 21:201-206. CHEN, L. (1992): Efficient deterministic parallel algorithms for integer sorting, Proceedings SCCI, 431-442.  ... 

Path Feasibility Analysis of BPEL Processes under Dead Path Elimination Semantics

Hongda WANG, Jianchun XING, Juelong LI, Qiliang YANG, Xuewei ZHANG, Deshuai HAN, Kai LI
2016 IEICE transactions on information and systems  
., dead path elimination (DPE) semantics, parallelism, etc.) of BPEL language have raised enormous problems to it, especially in path feasibility analysis of BPEL processes.  ...  Since BPEL processes support both parallelism and DPE semantics, existing techniques can't be directly applied to its path feasibility analysis.  ...  This work was partially supported by the National Natural Science Foundation of China under Grant NO. 61321491 and the Foundation of State Key Laboratory for Novel Software Technology under Grant NO.  ... 
doi:10.1587/transinf.2015edp7121 fatcat:w7k2z64vljedbjl3rloqg6bbkm

Workflow Patterns in Orc [chapter]

William R. Cook, Sourabh Patwardhan, Jayadev Misra
2006 Lecture Notes in Computer Science  
These patterns are useful for evaluating the capabilities of workflow systems and models.  ...  A key feature of the Orc implementations is that they are expressed as definitions that can be reused as needed.  ...  Overview of Orc An Orc program consists of a set of definitions and a goal expression which is to be evaluated.  ... 
doi:10.1007/11767954_6 fatcat:fowmdyrn7vdudginxsix7f5cyy

A survey of parallel execution strategies for transitive closure and logic programs

Filippo Cacace, Stefano Ceri, Maurice Houtsma
1993 Distributed and parallel databases  
to query processing.  ...  We observe that research on parallel execution of recursive queries is separated into two distinct subareas, one focused on the transitive closure of Relational Algebra expressions, the other one focused  ...  This research is partially supported by the LOGIDATA+ Project of the National Research Council of Italy.  ... 
doi:10.1007/bf01264013 fatcat:pe4vicsr3vctzoj437towrkdv4

Introduction to the Special Issue on the 18th International Symposium on Computer Architecture and High Performance Computing

Alberto F. De Souza, Rajkumar Buyya
2008 International journal of parallel programming  
In the fourth paper, The ParTriCluster Algorithm for Gene Expression Analysis, Araujo et al. present a parallel version of the Tricluster algorithm, which is used in bioinformatics for finding 3D clusters  ...  of genes, samples and timestamps; i.e., groups of genes that show similar cellular expression across many biological samples over similar time periods.  ... 
doi:10.1007/s10766-007-0065-y fatcat:ta7z4l4yyfcxjm4n5davlbk3oq
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