cient Locking for Shared Memory Database Systems 1
نویسندگان
چکیده
Signi cant performance advantages can be realized by implementing a database system on a shared memory multiprocessor. An e cient implementation of a lock manager is a prerequisite for e cient transaction processing in multiprocessor database systems. To this end, we advocate adopting an autonomous locking strategy. In autonomous locking, transactions acquire and release locks via operations on shared memory, in contrast to conventional locking where communication with a lock manager is involved. We demonstrate the superior performance and scalability of autonomous locking through benchmarks of a prototype lock manager implemented on a large scale shared memory multiprocessor. For instance, when contention is high (i.e., for hot lock operations), the performance of autonomous locking is nearly an order of magnitude better than conventional locking. The paper also addresses issues related to recovery (assuming independent node failures). 1 Partially supported by the National Science Foundation under grant IRI-9109210
منابع مشابه
Locking Protocols for Large - ScaleCache - Coherent Shared Memory
Signiicant performance advantages can be realized by implementing a database system on a cache-coherent shared memory multiprocessor. An eecient implementation of a lock manager is a prerequisite for eecient transaction processing in multiprocessor database systems. To this end, we examine two approaches to the implementation of locking in a cache-coherent shared memory multiprocessor database ...
متن کاملHighly Concurrent Locking in Shared Memory Database Systems
In parallel database systems, conflicts for accesses to objects are solved through object locking. In order to acquire and release locks, in the standard implementation of a lock manager small sections of the code may be executed only by a single thread. On massively parallel shared memory machines (SMM) the serialization of these critical sections leads to serious performance degradation. We e...
متن کاملLightweight Locking for Main Memory Database Systems
Locking is widely used as a concurrency control mechanism in database systems. As more OLTP databases are stored mostly or entirely in memory, transactional throughput is less and less limited by disk IO, and lock managers increasingly become performance bottlenecks. In this paper, we introduce very lightweight locking (VLL), an alternative approach to pessimistic concurrency control for main-m...
متن کاملEfficient Locking and Caching of Data in the Multisystem Shard Disks Transaction Environment
This paper describes a technique for use when multiple instances of a data base management system (DBMS), each with its own cache (buffer pool), can directly read and modify any data stored on a set of shared disks. Global locking and coherency control protocols are necessary in this context for assuring transaction consistency and for maintaining coherency of the data cached in the multiple ca...
متن کاملEvaluating Cache Coherence in the DSMIO System
There has been a significant amount of research on object-based database management systems (ODBMS). In contrast to traditional relational systems, ODBMS use the same data model for the clients and the server. Thus, parallel ODBMS typically adopt a data-shipping architecture, which allows data request processing to be performed at the clients. Although such a strategy can improve performance by...
متن کامل