The Time Warp Mechanism for Database Concurrency Control (original) (raw)

Performance of time warp protocols for transaction management in object-oriented systems

1994

It has been pointed out (e.g., by Richard Fujimoto) that protocols developed for the difficult problem of parallel and distributed simulation can also be adapted to other distributed applications. Indeed, in the mid 1980's David Jefferson adapted his Time Warp protocol to the problem of database concurrency control. In the present work, we consider our own variants of the Time Warp for database concurrency control, and perform a simulation study to compare their performance with other more traditional protocols. The performance results obtained for the Time Warp protocol are very encouraging. The initial motivation for developing and analyzing these variants of Time Warp was to find a high performance protocol suitable for a Query Driven

IJERT-Analysis of Effectiveness of Concurrency Control Techniques in Databases Ruchi Dagar

International Journal of Engineering Research and Technology (IJERT), 2012

https://www.ijert.org/analysis-of-effectiveness-of-concurrency-control-techniques-in-databases https://www.ijert.org/research/analysis-of-effectiveness-of-concurrency-control-techniques-in-databases-IJERTV1IS5487.pdf There is an ever-increasing demand for more complex transactions and higher throughputs in transaction processing systems leading to higher degrees of transaction concurrency. In this paper, we have analyzed different techniques of concurrency control in distributed databases and compared their performance. Ideas that are used in the design, development, and performance of concurrency control mechanisms have been summarized. The locking, time-stamp, optimistic-based mechanisms are included.

Implementation of transaction and concurrency control support in a temporal DBMS* 1

Information Systems, 1998

¾ Transactions and concurrency control are significant features in database systems, facilitating functions both at user and system level. However, the support of these features in a temporal DBMS has not yet received adequate research attention. In this paper, we describe the techniques developed in order to support transaction and concurrency control in a temporal DBMS that was implemented as an additional layer to a commercial DBMS. The proposed techniques make direct use of the transaction mechanisms of the DBMS. In addition, they overcome a number of limitations such as automatic commit points, lock release and log size increment, which are imposed by the underlying DBMS. Our measurements have shown that the overhead introduced by these techniques is negligible, less than 1% in all cases. The approach undertaken is of general interest, it can also be applied to non-temporal DBMS extensions.

A unified concurrency control algorithm for distributed database systems

Proceedings. Fourth International Conference on Data Engineering

We present a unified concurrency control algorithm for distributed database systems in which each transaction may choose its own concurrency control protocol. Specifically, we integrate Two-Phase Locking, Timestamp Ordering, and Precedence Agreement into one unified concurrency control scheme. We show the correctness of the new scheme and study the problem of selecting the best protocol for each transaction in order to optimize system performance.

Implementation of transaction and concurrency control support in a temporal DBMS

Information Systems, 1998

¾ Transactions and concurrency control are significant features in database systems, facilitating functions both at user and system level. However, the support of these features in a temporal DBMS has not yet received adequate research attention. In this paper, we describe the techniques developed in order to support transaction and concurrency control in a temporal DBMS that was implemented as an additional layer to a commercial DBMS. The proposed techniques make direct use of the transaction mechanisms of the DBMS. In addition, they overcome a number of limitations such as automatic commit points, lock release and log size increment, which are imposed by the underlying DBMS. Our measurements have shown that the overhead introduced by these techniques is negligible, less than 1% in all cases. The approach undertaken is of general interest, it can also be applied to non-temporal DBMS extensions.

A Distributed Architecture for Transactions Synchronization in Distributed Database Systems

International Journal

Various concurrency control algorithms have been proposed for use in distributed database systems. But, the number of algorithms available for the distributed concurrency control, come into one of three basic classes: locking algorithms, Timestamp algorithms and optimistic (or certification) algorithms. In this paper we are presenting a Distributed Transaction Processing Model and an approach for concurrency control in distributed database systems. The analysis of our approach is a decomposition of the concurrency control problem into two major sub-problems: read-write and write-write synchronization. We describe a series of synchronization techniques for solving each sub-problem and will show how to combine these techniques into algorithms for solving the entire concurrency control problem. Such algorithms are called "concurrency control methods". Our approach concentrates on the structure and correctness of concurrency control methods and also the performance of such methods up to some extent.

Concurrency Control in Distributed Object-Oriented Database Systems

A family of optimistic concurrency control protocols for real-time persistent systems with critical performance requirements and very tight deadlines is proposed. Under assumptions that almost all transactions are extremely short and read-only and the entire database resides in main memory (which are realistic for this type of applications), we propose distributed concurrency control protocols which exploit the virtual memory management for concurrency control. Virtual memory management is required anyway, so the additional overhead is extremely low, especially for most frequent read-only transactions. Two variations of the proposed protocol are described and compared with alternative approaches.

Transaction synchronisation in object bases

Journal of Computer and System Sciences, 1991

We propose a formal model of concurrency control in object bases. An object base is like a database except that information is represented in terms of \objects" that encapsulate both data and the procedures through which the data can be manipulated. The model generalises the classical model of database concurrency control: it allows for nested transactions (as opposed to at transactions) which may issue arbitrary operations (as opposed to just read and write operations). We establish an analogue to the classical serialisability theorem and use it to derive simple proofs of correctness of two concurrency control algorithms for object bases, namely Nested Two-Phase Locking (Moss' algorithm) and Nested Timestamp Ordering (Reed's algorithm).

A Review on Concurrency Control Techniques in Database Management Systems

Kafrelsheikh Journal of Information Sciences

Conflicts, deadlock and rolled-back transactions are being considered as the most recent challenges related to executing the transaction concurrently on different environments of Database Management Systems (DBMS). More precisely, in distributed database systems, to handle and avoid these challenges, there are different techniques and protocols are utilized. In this paper, we highlight some of these techniques which includes Two-Phase Commit (2PC) protocol and Three-Phase Commit (3PC) protocol) as well as and Deadlock-Free Cell lock (DFCL) algorithm. Moreover, the paper surveys all these protocols and demonstrate the pros and cons of each techniques. Afterwards, we proposed the solution of some important problems related to concurrency control techniques in DBMS