Software is pervasive in our daily lives. Unfortunately, software bugs can severely affect the dependability and security of software systems. Among all types of software bugs, the concurrency bug is one of the most troublesome and important. Concurrency bugs widely exist in concurrent programs. They are difficult to detect and diagnose because of their unique non-determinism. In the real world...

Concurrency control schemes for object-oriented database systems (OODBSs) used in the area of performance-critical applications should increase the degree of concurrency and decrease locking overhead in order to offer maximum performance. However, most commercially available OODBSs use conventional concurrency control schemes that never exploit the rich semantics of object-oriented data model, ...

Concurrency control is the activity of synchronizing database operations by concurrently executing transactions on a shared database. We examine the problem of concurrency control when the database supports multiple versions of the data. Multiversion concurrency control is used in order to improve the level of achievable concurrency. The goal is to produce an execution that has the same effect ...

Increasing significance and popularity of XML is the main reason why many commercial object-relational database management systems (ORDBMSs) developed XML storage and processing functionality. Additionally, there are new types of specialized database systems known as ’native’ XML database systems. As we know, concurrency control is one of the most important mechanisms in DBMSs. Unfortunately, c...

Increasing significance and popularity of XML is the main reason why many commercial object-relational database management systems (ORDBMS’s) developed XML storage and processing functionality. Additionally, there are new types of specialized database systems known as ’native’ XML database systems. As we know, concurrency control is one of the most important mechanisms in DBMS’s. Unfortunately,...

The concurrency is classified into two types: structured concurrency and nonstructured concurrency. After showing that the nonstructured concurrency cannot be represented by the conventional notations in the Petri net language, a method to represent such concurrency by the language is proposed. The proposed method allows us to utilize the existing approaches for analyzing properties of a nonstr...

The importance of concurrency (i.e., multiple overlapping sexual partnerships) in driving HIV epidemics has been hotly debated in the past 20 years. Some have hypothesized that concurrency is an extremely important driver of HIV epidemics and may explain the high prevalence of HIV in the general population of many sub-Saharan African countries. Notably, proponents of this hypothesis acknowledge...

The granularity of concurrency control has a big impact on the performance of transactional systems. Concurrency control granularity and data granularity (data size) are usually the same. The e ect of this coupling is that if a coarse granularity is used, the overhead of data access (number of disk accesses) is reduced, but also the degree of concurrency. On the other hand, if a ne granularity ...

Java’s direct support for concurrency has enticed many programmers to tackle concurrent programming using this new language. The use of concurrency adds a new dimension of complexity to application development and introduces its own unique set of problems. We look at concurrency in the context of the latest version of the Java language and libraries, and employ proven design-patterns and coding...

This paper describes the integration of concurrency control in Balloon, an object-oriented language that separates the concepts of type and class as well of subtyping and subclassing. Types are interface speciications enriched with concurrency control annotations. Classes are used to implement the operational functionality of types as well as concurrency control mechanisms. Types, classes and c...