Locking performance in centralized databases
ACM Transactions on Database Systems (TODS)
Distributed Version Management for Read-Only Actions
IEEE Transactions on Software Engineering - Special issue on distributed systems
Concurrency control and recovery in database systems
Concurrency control and recovery in database systems
Concurrency control performance modeling: alternatives and implications
ACM Transactions on Database Systems (TODS)
High contention in a stock trading database: a case study
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
Modular synchronization in multiversion databases: version control and concurrency control
SIGMOD '89 Proceedings of the 1989 ACM SIGMOD international conference on Management of data
Concurrency control for high contention environments
ACM Transactions on Database Systems (TODS)
Parallel database systems: open problems and new issues
Distributed and Parallel Databases - Special issue: Research topics in distributed and parallel databases
On optimistic methods for concurrency control
ACM Transactions on Database Systems (TODS)
Multiversion concurrency control—theory and algorithms
ACM Transactions on Database Systems (TODS)
Parallelism and recovery in database systems
ACM Transactions on Database Systems (TODS)
Distributed database concurrency controls using before-values
SIGMOD '81 Proceedings of the 1981 ACM SIGMOD international conference on Management of data
The implementation of an integrated concurrency control and recovery scheme
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
Effective Optimistic Concurrency Control in Multiversion Object Bases
ISOOMS '94 Proceedings of the International Symposium on Object-Oriented Methodologies and Systems
On the Correctness of a Transaction Model for Mobile Computing
DEXA '98 Proceedings of the 9th International Conference on Database and Expert Systems Applications
A Transaction Model to Improve Data Availability in Mobile Computing
Distributed and Parallel Databases
A Multi-version Transaction Model to Improve Data Availability in Mobile Computing
On the Move to Meaningful Internet Systems, 2002 - DOA/CoopIS/ODBASE 2002 Confederated International Conferences DOA, CoopIS and ODBASE 2002
A transaction model and multiversion concurrency control for mobile database systems
Distributed and Parallel Databases
| Hi-index | 0.00 |
Multiversions of data are used in database systems to increase concurrency and to provide efficient recovery. Data versions improves the concurrency by allowing the concurrent execution of "non-conflicting" read-write lock requests on different versions of data in an arbitrary fashion. A transaction that accesses a data item version which is later diagnosed to lead to an incorrect execution, is aborted. This act is reminiscent of the validation phase in the optimistic concurrency control schemes. Various performance studies suggest that these schemes perform poorly in high data contention environments where the excessive transaction aborts result due to the failed validation. We propose an adaptable constrained two-version two-phase locking (C2V2PL) scheme in which these "non-conflicting" requests are allowed only in a constrained manner. C2V2PL schemes assumes that a lock request failing to satisfy the specific constraints will lead to an incorrect execution and hence, must be either rejected or blocked. This eliminates the need for a separate validation phase. When the contention for data among the concurrent transactions is high, the C2V2PL scheduler in aggressive state rejects such lock requests. The deadlock free nature of C2V2PL scheduler adapts to the low data contention environments by accepting the lock request that have failed the specific constraints but contrary to the assumption, will not lead to an incorrect execution. Thus improving the performance due to reduced transaction aborts in this conservative state.