Filters








3,052 Hits in 2.2 sec

Locking Timestamps versus Locking Objects

Marcos K. Aguilera, Tudor David, Rachid Guerraoui, Junxiong Wang
2018 Proceedings of the 2018 ACM Symposium on Principles of Distributed Computing - PODC '18  
The key idea behind MVTL is simple: lock individual time points instead of locking objects or versions.  ...  We present multiversion timestamp locking (MVTL), a new genre of multiversion concurrency control algorithms for serializable transactions.  ...  MVTL is based on a simple idea: use locks as in lock-based algorithms, but lock individual timestamps of objects, rather than entire objects at a time.  ... 
doi:10.1145/3212734.3212742 fatcat:kyo7binpgbcwjmryoikesgvm2a

Pulsating STM – The in-memory Optimistic Concurrency Control Technique for Multi Core Systems

2019 International Journal of Engineering and Advanced Technology  
The technique is lock free and is based upon timestamping. Threads involved in the proposed approach possess the transactional properties of atomicity, concurrency and isolation.  ...  Being lock free, the algorithm is better than the existing lock-based techniques.  ...  This paper has done detailed study of the various STM tradeoffs like optimistic concurrency control versus pessimistic concurrency control; undo logging versus write buffering and object based versus cache  ... 
doi:10.35940/ijeat.a9525.109119 fatcat:nhmqgac2brd6td3swao2oo4woq

The Performance of Concurrency Control Algorithms for Database Management Systems

Michael J. Carey, Michael Stonebraker
1984 Very Large Data Bases Conference  
The basic algorithms studied include four locking algorithms. two timestamp algorithms. and one optimistic algorithm.  ...  We show that. in general, locking algorithms provide the best performance.  ...  The objective of this experiment was to observe the effects of random versus sequential object access patterns on algorithm performance.  ... 
dblp:conf/vldb/CareyS84 fatcat:xa7urfvz6jdnxgin5olhlcrgn4

Measured Performance of Time Interval Concurrency Control Techniques

Jerre D. Noe, David B. Wagner
1987 Very Large Data Bases Conference  
This paper reports on an implementation of Bayer's Time Interval concurrency control method and compares it to the performance of a conventional timestamp method.  ...  For each object version on which T has a commit lock, all read locks on all previous versions of the object must already have been deleted.  ...  Fixed Timestamps versus Dynamic Time Intervals In a fixed timestamp method (hereafter referred to simply as TS) timestamps are chosen for transactions when they begin.  ... 
dblp:conf/vldb/NoeW87 fatcat:revebs5fbredtgxqfckqo2pyiy

Composable, nestable, pessimistic atomic statements

Zachary Anderson, David Gay
2011 Proceedings of the 2011 ACM international conference on Object oriented programming systems languages and applications - OOPSLA '11  
Similar to systems using locks, our implementation requires programmers to annotate the types of objects with the shelters that protect them, and indicate the sections of code to be executed atomically  ...  Unlike previous lock-based pessimistic approaches, our mechanism does not require a whole-program analysis that computes a global lock order.  ...  respect to the locking runs versus the number of threads used.  ... 
doi:10.1145/2048066.2048132 dblp:conf/oopsla/AndersonG11 fatcat:44sslc7m6valvflam4derzkthu

Concurrency versus availability: atomicity mechanisms for replicated data

Maurice Herlihy
1987 ACM Transactions on Computer Systems  
A replicated object is a typed data object that is stored redundantly at multiple locations to enhance availability.  ...  All the information used by the consensus-locking protocol (such as commit timestamps and locks) can be reconstructed from this schedule.  ...  a totally ordered set of timestamps.  ... 
doi:10.1145/24068.27643 fatcat:ayrptvmbcja7xirxv3lnuyleo4

Apologizing versus asking permission: optimistic concurrency control for abstract data types

M. Herlihy
1990 ACM Transactions on Database Systems  
These techniques are also modular: they can be applied selectively on a per-object (or even per-operation) basis in conjunction with standard pessimistic techniques such as two-phase locking, permitting  ...  Unlike many methods that classify operations only as Reads or Writes, these techniques systematically exploit type-specific properties of objects to validate more interleavings.  ...  As each transaction commits, it is issued a logical timestamp [ 281. Each object must ensure that transactions are serializable in commit timestamp order.  ... 
doi:10.1145/77643.77647 fatcat:esgrws2w5vayfnv6g44vmpq4fi

Multi-Version-Pulsating STM: A Multi-Version Optimistic Concurrency Control Scheme for Highly Parallel in-Memory Workload in a Multi Core Environment

2019 International Journal of Engineering and Advanced Technology  
Being lock free and employing lazy timestamp calculations, this approach is better than other existing concurrency control approaches.  ...  This paper presents a multi-version optimistic concurrency control algorithm based on timestamping. This algorithm is lock free and is tested on 64 simulated CPU cores on a multi core simulator.  ...  As it is a lock-free approach it is undoubtedly better than many lock based STM algorithms in literature.  ... 
doi:10.35940/ijeat.a9526.109119 fatcat:wpo7dpljdndopnf7e3t7wqqrsy

WTTM 2012, the fourth workshop on the theory of transactional memory

Vincent Gramoli, Alessia Milani
2012 ACM SIGACT News  
The objective of WTTM was to discuss new theoretical challenges and recent achievements in the area of transactional computing. The workshop took place on July 19, 2012, in Madeira, Portugal.  ...  To investigate different directions in the design space (lazy versus eager conflict detection, multiversion versus single version etc), they consider the following transactional memories: JVSTM [9] ,  ...  This technique exploits the object semantics to synchronize concurrent accesses to the object.  ... 
doi:10.1145/2421119.2421141 fatcat:ki2pxs4enrggfkpsj2jys76prm

A Lock-Free O(1) Event Pool and Its Application to Share-Everything PDES Platforms

Romolo Marotta, Mauro Ianni, Alessandro Pellegrini, Francesco Quaglia
2016 2016 IEEE/ACM 20th International Symposium on Distributed Simulation and Real Time Applications (DS-RT)  
In this article we present a lock-free event pool which also provides amortized O(1) time complexity for both insertions and extractions.  ...  This model is based on loose coupling between simulation objects and threads, lasting (as an extreme) no more than the lifetime of individual events.  ...  object.  ... 
doi:10.1109/ds-rt.2016.33 dblp:conf/dsrt/MarottaI0Q16 fatcat:ezm24oppjrdhfkn6rdb2lbf7x4

Distributed optimistic concurrency control methods for high-performance transaction processing

A. Thomasian
1998 IEEE Transactions on Knowledge and Data Engineering  
We present a distributed OCC method followed by locking, such that locking is an integral part of distributed validation and two-phase commit.  ...  We also describe several interesting variants of the proposed OCC method, including methods for handling access variance, i.e., when rerunning a transaction results in accesses to a different set of objects  ...  It should be emphasized that access locks obviate the need for maintaining object timestamps and can also be used with the optimistic die policy.  ... 
doi:10.1109/69.667102 fatcat:nb7yoajp2jehzc5cm62a6bngpa

Fast and lock-free concurrent priority queues for multi-thread systems

Håkan Sundell, Philippas Tsigas
2005 Journal of Parallel and Distributed Computing  
The experimental results clearly show that our lock-free implementation outperforms the other lock-based implementations in practical scenarios for 3 threads and more, both on fully concurrent as well  ...  We present an efficient and practical lock-free implementation of a concurrent priority queue that is suitable for both fully concurrent (large multi-processor) systems as well as pre-emptive (multi-process  ...  To ensure consistency of a shared data object in a concurrent environment, the most common method is to use mutual exclusion, i.e. some form of locking.  ... 
doi:10.1016/j.jpdc.2004.12.005 fatcat:ksg3hmjdonffzgo6aw5jto27ky

Integrated concurrency control and recovery mechanisms: design and performance evaluation

Rakesh Agrawal, David J. Dewitt
1985 ACM Transactions on Database Systems  
Basic Timestamp Ordering Versus Locking For centralized database systems, the basic timestamp ordering algorithm is very similar to locking in its behavior but has the disadvantage of inducing a larger  ...  A read request for an object by a transaction is accepted only if no other transaction with a larger timestamp has written that object.  ... 
doi:10.1145/4879.4958 fatcat:xwzympk4ofhurespdlui53pkga

Analysis of locking behavior in three real database systems

Vigyan Singhal, Alan Jay Smith
1997 The VLDB journal  
This study considers topics such as frequency of locking and unlocking, deadlock and blocking, duration of locks, types of locks, correlations between applications of lock types, two-phase versus non-two-phase  ...  locking, when locks are held and released, etc.  ...  Timestamps In two of the traces, bank and transport, all trace entries are tagged with a timestamp.  ... 
doi:10.1007/s007780050032 fatcat:q427fifez5g55obiltvzgvtvoe

Consistent Replication in Distributed Multi-Tier Architectures

Thomas Repantis, Arun Iyengar, Vana Kalogeraki, Isabelle Rouvellou
2011 Proceedings of the 7th International Conference on Collaborative Computing: Networking, Applications and Worksharing  
Lock-based approaches [16] use a lock manager to achieve this goal. Timestamp-based approaches [16] utilize the generation of an agreed timestamp ordering between the replicas.  ...  The taxonomy presented includes eager replication (strong consistency) versus lazy replication (weak consistency), as well as group replication, in which all replicas accept writes versus master replication  ... 
doi:10.4108/icst.collaboratecom.2011.247116 dblp:conf/colcom/RepantisIKR11 fatcat:mb5taoz4kfcuvgubqpims7yfee
« Previous Showing results 1 — 15 out of 3,052 results