These advantages do not come for free. The challenge of this architecture (as of any clustered or distributed architecture) is to provide data coherency for the independent users of the system. The way to do that is to use locking. Oracle uses multiple level locking: row locks on transaction levels, instance locks within instances, and global locks among the instances. The latter are specific t...

Scalable architectures with non-uniform memory access time (NUMAs) have gained increased popularity in recent years. The increased scalability have increased the demand for scalable lock implementations, such as the queue-based locks of Mellor-Crummey and Scott (MCS lock), and of Craig, Landin and Hagersten (CLH lock). This paper demonstrates that the first-come first-served nature of queue-bas...

This paper identifies node affinity as an important property for scalable general-purpose locks. Nonuniform communication architectures (NUCAs), for example CCNUMAs built from a few large nodes or from chip multiprocessors (CMPs), have a lower penalty for reading data from a neighbor’s cache than from a remote cache. Lock implementations that encourages handing over locks to neighbors will impr...

The problem of model checking threads interacting purely via the standard synchronization primitives is key for many concurrent program analyses, particularly dataflow analysis. Unfortunately, it is undecidable even for the most commonly used synchronization primitive, i.e., mutex locks. Lock usage in concurrent programs can be characterized in terms of lock chains, where a sequence of mutex lo...

Operating system kernels typically ooer a xed and limited set of primitives and underlying mechanisms for use by application programs. However, the attainment of high performance for a variety of parallel applications may require the availability of additional primitives or of variants of existing primitives best suited for speciic applications. Furthermore, operating system mechanisms must als...

The scalability of multithreaded applications on current multicore systems is hampered by the performance of lock algorithms, due to the costs of access contention and cache misses. In this paper, we propose a new lock algorithm, Remote Core Locking (RCL), that aims to improve the performance of critical sections in legacy applications on multicore architectures. The idea of RCL is to replace l...

A Dynamic Pushdown Network (DPN) is a set of pushdown systems (PDSs) where each process can dynamically create new instances of PDSs. DPNs are a natural model of multi-threaded programs with (possibly recursive) procedure calls and thread creation. Extending DPNs with locks allows processes to synchronize with each other. Thus, DPNs with locks are a well adapted formalism to model multi-threade...

SAP ® Adaptive Server ® Enterprise is a high-performance relational database management system for mission-critical, data-intensive environments. It ensures highest operational efficiency and throughput on a broad range of platforms. Configuring locks in SAP ASE includes understanding locking and data consistency, the granularity of locks, types of locks, lock compatibility, and how isolation l...

Operating system kernels typically ooer a xed set of mechanisms and primitives. However, recent research shows that the attainment of high performance for a variety of parallel applications may require the availability of variants of existing primitives or additional low-level mechanisms best suited for speciic applications. One approach to addressing this need is to ooer an adaptable and exten...