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A Scalable Framework for Serializable XQuery [chapter]

Sebastian Bächle, Theo Härder
2010 Communications in Computer and Information Science  
This paper focuses on an aspect that is widely neglected in native XML database management systems: support for concurrent transactional access.  ...  All concepts shown were implemented in our research prototype resulting in a scalable framework for serializable XQuery.  ...  Unfortunately, knowledge about potential contention within a document is not sufficient to establish maximal permissive concurrency control.  ... 
doi:10.1007/978-3-642-14306-9_68 fatcat:3sf3bnjagzcbzeuk6v2yilx2au

Logical Concurrency Control from Sequential Proofs

Jyotirmoy Deshmukh, G. Ramalingam, Venkatesh-Prasad Ranganath, Kapil Vaswani, Michael Hicks
2011 Logical Methods in Computer Science  
We are interested in identifying and enforcing the isolation requirements of a concurrent program, i.e., concurrency control that ensures that the program meets its specification.  ...  ., a proof of correctness of the program in the absence of concurrent interleavings.  ...  In [20] , the key goal is to obtain a maximally concurrent program for a given cost.  ... 
doi:10.2168/lmcs-7(3:10)2011 fatcat:6o2zlx4rnvg2rg5nmjrdjs6yui

Logical Concurrency Control from Sequential Proofs [chapter]

Jyotirmoy Deshmukh, G. Ramalingam, Venkatesh-Prasad Ranganath, Kapil Vaswani
2010 Lecture Notes in Computer Science  
We are interested in identifying and enforcing the isolation requirements of a concurrent program, i.e., concurrency control that ensures that the program meets its specification.  ...  ., a proof of correctness of the program in the absence of concurrent interleavings.  ...  In [20] , the key goal is to obtain a maximally concurrent program for a given cost.  ... 
doi:10.1007/978-3-642-11957-6_13 fatcat:krusesmqobb5nnifhvbg6pvvay

Database Isolation By Scheduling

Kevin P. Gaffney, Robert K. Claus, Jignesh M. Patel
2021 Proceedings of the VLDB Endowment  
Our work builds on predicate locking, an isolation mechanism that enables this modularization by locking logical rather than physical items in a database.  ...  Predicate locking is rarely used as the core isolation mechanism because of its high theoretical complexity and perceived overhead.  ...  ACKNOWLEDGMENTS This work was supported in part by CRISP, one of six centers in JUMP, a Semiconductor Research Corporation (SRC) program, sponsored by MARCO and DARPA.  ... 
doi:10.14778/3461535.3461537 dblp:journals/pvldb/GaffneyCP21 fatcat:nngx4pmvxrendj3tkv2emfzvie

Multiversion concurrency control for large-scale service directories

W. Binder, I. Constantinescu, B. Faltings, S. Spycher
2005 Third European Conference on Web Services (ECOWS'05)  
In this paper we describe the implementation of multiversion concurrency control on the Generalized Search Tree (GiST), an index structure introduced by Hellerstein.  ...  However, the solutions that have been proposed to address concurrency control on the GiST do not meet the requirements of large-scale service directories.  ...  An alternative concurrency control mechanism for the GiST is discussed in [4] , which uses granular locking instead of predicate locking.  ... 
doi:10.1109/ecows.2005.18 dblp:conf/icws/BinderCFS05 fatcat:efyskv3nqbadfcnbf27lznbhvy

Transactional predication

Nathan G. Bronson, Jared Casper, Hassan Chafi, Kunle Olukotun
2010 Proceeding of the 29th ACM SIGACT-SIGOPS symposium on Principles of distributed computing - PODC '10  
Concurrent collection classes are widely used in multi-threaded programming, but they provide atomicity only for a fixed set of operations.  ...  We introduce transactional predication, a method for building transactional maps and sets on top of an underlying non-composable concurrent map.  ...  provides its own concurrency control.  ... 
doi:10.1145/1835698.1835703 dblp:conf/podc/BronsonCCO10 fatcat:3xuzjr767ven5c4j6nbvzdonle

An Optimal Predicate Locking Scheduler

Carlo Meghini, Costantino Thanos
1996 Journal of computer and system sciences (Print)  
The paper presents a predicate locking scheduler that maximizes concurrency by locking as many of the database entities as possible without compromising the correctness of execution of the database transactions  ...  The scheduling strategy that guarantees the maximal concurrency is first identified, then a predicate language allowing an efficient implementation of this strategy is given.  ...  A number of algorithms for concurrency control protocols have been proposed, implemented and used in commercial systems. The most common technique for concurrency control is locking.  ... 
doi:10.1006/jcss.1996.0080 fatcat:oa7ashxjo5emxer5plcclfvtea

Semantic Quality Attributes for Big-Step Modelling Languages [chapter]

Shahram Esmaeilsabzali, Nancy A. Day
2011 Lecture Notes in Computer Science  
In a BSML, a model's reaction to an environmental input is a sequence of small steps, each of which can consist of the execution of a set of transitions from multiple concurrent components.  ...  In this paper, we introduce three semantic quality attributes for the family of big-step modelling languages (BSMLs).  ...  For example, in the model in Fig. 1 , the scope of t 4 is Lock and the arena of t 8 is the root Or control state not shown in the figure.  ... 
doi:10.1007/978-3-642-19811-3_6 fatcat:nytmhlbrbnb5petxy4r3vsdsum

Key Range Locking Strategies for Improved Concurrency

David B. Lomet
1993 Very Large Data Bases Conference  
However, records that satisfy the eeleclion predicate muat be locked even when they are nol present in the database to prevent their insertion.  ...  One way to cope with phantoms is through range locking, 4 limited form of predicate locking. We investigate lock modes for ranges and describe new lock modes lhal greatly increase concurrency.  ...  Subsequent interactions with Russ were very helpful in working out the concepts presented in this paper. Jim Gray provided comments and encouragement.  ... 
dblp:conf/vldb/Lomet93 fatcat:locgrkzpkbh2pj5sysqesxft6m

A parallel algorithm for global states enumeration in concurrent systems

Yen-Jung Chang, Vijay K. Garg
2015 Proceedings of the 20th ACM SIGPLAN Symposium on Principles and Practice of Parallel Programming - PPoPP 2015  
One of the verification methods is predicate detection, which predicts whether the user specified condition (predicate) could become true in any global states of the program.  ...  Verifying the correctness of the executions of a concurrent program is difficult because of its nondeterministic behavior.  ...  Acknowledgments This research is supported in part by National Science Foundation awards CNS-1346245 and CNS-1115808 and the Cullen Trust for Higher Education.  ... 
doi:10.1145/2688500.2688520 dblp:conf/ppopp/ChangG15 fatcat:kgozmzjtujhizfpt5cxyxr35dy

Hierarchical locking in B-tree indexes

Goetz Graefe
2007 Datenbanksysteme für Business, Technologie und Web  
Nonetheless, it increases concurrency among operations on individual keys and records beyond that enabled by traditional lock modes.  ...  In addition, a simplification of traditional key range locking is introduced that applies principled hierarchical locking to keys in B-tree leaves.  ...  Thus, locking key prefixes may be competitive with predicate locking and precision locking but without any need for predicate evaluation for concurrency control.  ... 
dblp:conf/btw/Graefe07 fatcat:gfxl7lswlfgjdddphzxxyf5fa4

Simplifying Linearizability Proofs with Reduction and Abstraction [chapter]

Tayfun Elmas, Shaz Qadeer, Ali Sezgin, Omer Subasi, Serdar Tasiran
2010 Lecture Notes in Computer Science  
We have implemented our method in the QED verifier and demonstrated its effectiveness and practicality on several highly-concurrent examples from the literature.  ...  If the concurrent program uses fine-grained concurrency and complex synchronization, constructing such a proof is difficult.  ...  S[x]==|{ i | 0<=i<N && M[i].elt==x What is noteworthy about the proof we outlined is that it handles two separate concerns in separate proof steps: 1) concurrency control using locking and the stt field  ... 
doi:10.1007/978-3-642-12002-2_25 fatcat:s3jagpofzvgqdhmmi4drnbury4

The Notions of Consistency and Predicate Locks in a Database System [chapter]

K.P. Eswaran, J.N. Gray, R.A. Lorie, I.L. Traiger
1989 Readings in Artificial Intelligence and Databases  
An implementation of predicate locks which satisfies the consistency condition is suggested.  ...  Then it is argued that a transaction needs to lock a logical rather than a physical subset of the database. These subsets may be specified by predicates.  ...  In [8] a field was chosen as the basic unit of locking. This choice gives maximal concurrency but presents many notational complexities.  ... 
doi:10.1016/b978-0-934613-53-8.50039-x fatcat:bmaejdphkndj7be6fm6qhn4ijy

The notions of consistency and predicate locks in a database system

K. P. Eswaran, J. N. Gray, R. A. Lorie, I. L. Traiger
1976 Communications of the ACM  
An implementation of predicate locks which satisfies the consistency condition is suggested.  ...  Then it is argued that a transaction needs to lock a logical rather than a physical subset of the database. These subsets may be specified by predicates.  ...  In [8] a field was chosen as the basic unit of locking. This choice gives maximal concurrency but presents many notational complexities.  ... 
doi:10.1145/360363.360369 fatcat:kminye4jcratzexidkqg5qqwpa

Coo: Rethink Data Anomalies In Databases [article]

Haixiang Li, Xiaoyan Li, Yuxing Chen, Yuean Zhu, Xiaoyong Du, Wei Lu, Chang Liu, Anqun Pan
2021 arXiv   pre-print
In addition, we use this framework to define new isolation levels and quantitatively describe the concurrency and rollback rate of mainstream concurrency control algorithms.  ...  Transaction processing technology has three important contents: data anomalies, isolation levels, and concurrent control algorithms.  ...  A good definition of isolation levels helps to maximize concurrent access control by using lowcost heuristic rules. • Simplicity.  ... 
arXiv:2109.06485v3 fatcat:l2v4teoggjfxvjfdtbm4emomty
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