209397194
Data Caching in Information Retrieval Systems.
52874049
Negotiating data access in federated database systems
A protocol is presented for negotiating access to data in a federated database. This protocol deals with several important aspects of data sharing in an environment where databases belonging to different organizations coexist and cooperate. It is based on the concept of quasicopies. These are cached values that are allowed to deviate from the central value in a controlled fashion. The degree of consistency of a quasicopy is established by the entity where the quasicopy is to reside. Two techniques are presented that can be used for numerical data and for copies that rely on version numbers. It is believed that these two ideas encompass many of the interesting cases in practice. However, it is also possible to fine tune the estimation of this function once the exact semantics of the data involved are known.<<ETX>>
41657422
Long-Term Caching Strategies for Very Large Distributed File Systems
5881433
An advisor for flexible working sets
The traditional model of virtual memory working sets does not account for programs that can adjust their working sets on demand. Examples of such programs are garbage-collected systems and databases with block cache buffers. We present a memory-use model of such systems, and propose a method that may be used by virtual memory managers to advise programs on how to adjust their working sets. Our method tries to minimize memory contention and ensure better overall system response time. We have implemented a memory “advice server” that runs as a non-privileged process under Berkeley Unix. User processes may ask this server for advice about working set sizes, so as to take maximum advantage of memory resources. Our implementation is quite simple, and has negligible overhead, and experimental results show that it results in sizable performance improvements.
16077675
Hybrid Multi-agent Systems: Integrating Swarming and BDI Agents
The individual agents that interact in a multi-agent system typically exist along a continuum ranging from heavyweight cognitive agents (often of the "BDI" type) to lightweight agents with limited individual processing (digital ants). Most systems use agents from a single position along this spectrum. We have successfully implemented several systems in which agents of very different degrees of internal sophistication interact with one another. Based on this experience, we identify several different ways in which agents of different kinds can be integrated in a single system, and offer observations and lessons from our experiences.
59895916
Concurrency Control and Recovery for Global Procedures in Federated Database Systems
42014672
Trade Press News - Announcement and Preface
29591299
Trade Press News