Ficus is a exible replication facility with optimistic concurrency control designed to span a wide range of scales and network environments. Support for partitioned operation is fundamental to the Ficus design but was not widely exercised in early Ficus use. This position paper reports recent experiences using Ficus in settings where some replicas are only occasionally connected to a network, a...

The interaction history of a document can be modelled as a tree of command objects. This model does not only support recovery (undo/redo), but is also suitable for cooperation between distributed users working on a common document. Various coupling modes can be supported. Switching between modes is supported by regarding different versions of a document as different branches of the history. Bra...

In this paper we present performance measurements in a cluster environment. First, we briefly explain our version of optimistic concurrency control and load balance. Then we compare performance and speed-up of a CORBAand an AspectC++-implementation of a distributed object server for pessimistic and optimistic concurrency control.

This extended abstract summarizes the state-of-the-art solution to the structuring problem for models that describe existing real world or envisioned processes. Special attention is devoted to models that allow for the true concurrency semantics. Given a model of a process, the structuring problem deals with answering the question of whether there exists another model that describes the process...

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 ...

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...

Concurrency control for Transactional Memory (TM) is investigated as a means for improving resource usage by adjusting dynamically the number of threads concurrently executing transactions. The proposed control system takes as feedback the measured Transaction Commit Rate to adjust the concurrency. Through an extensive evaluation, a new Concurrency Control Algorithm (CCA), called P-only Concurr...

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 ...

Many performance studies have shown that locking based protocols outperform other concurrency control protocols in most database configurations and workloads. However, in mobile environments there are many special characteristics, such as long network delay and the expensive wireless communication. Besides, transactions may be aborted due to forced termination when handoff occurs for the consid...