A Distributed System with a Centralized Organization

UNIX has been around now for almost 20 years. At the time UNIX began, most departments felt themselves well-endowed indeed if they owned a single PDP-11/45 with 256K memory and a 2.5M RK05 disk. Nowadays a laptop would be embarrassed to have only that. It is our hypothesis that UNIX is no longer the appropriate kind of operating system for the 1990s. In this paper, a new system, Amoeba, will be described, that we believe meets the requirements for distributed computing in the 1990s.

Computer, 1991

udging from the enormous amount of distributed-system research carried out over the past decade, information processing experts have come t o recognize the advantages these systems possess. These research activ-J ities have led to the availability of more than 50 network and distributed systems. However, most of these systems can only partially succeed in attaining the major goals of a distributed system, which include transparency, higher performance, higher reliability and availability, and higher scalability. Of course, attaining all these goals in the first attempt is impossible. Nonetheless, gradual improvements are possible by learning from existing systems and trying to overcome their limitations. The University of Tokyo's Galaxy research project attempts to design, implement, and use a distributed computing environment based on this idea. Design goals and novel aspects Analyzing why existing In designing Galaxy, our primary goal was to build a distributed operating system suitable for use in both local and widearea network workstations. T o achieve this goal, we eliminated the use of broadcast protocols in any of our mechanisms, avoided the use of global-locking o r time-stamp-ordering mechanisms while maintaining the consistency of replicated information, and decentral-distributed systems are limited, the Galaxy research project borrows many concepts and proposed facilities ized the management of all globally useful information. novel system features that helped us achieve this goal include O u r second major goal was to ensure high performance. Design decisions and and integrates them developing the Galaxy kernel from scratch, rather than modifying a n existing using multiple-level interprocess communication mechanisms to meet the with its own novel Unix kernel; design features.

ACM Computing Surveys, 1985

Distributed operating systems have many aspects in common with centralized ones, but they also differ in certain ways. This paper is intended as an introduction to distributed operating systems, and especially to current university research about them. After a discussion of what constitutes a distributed operating system and how it is distinguished from a computer network, various key design issues are discussed. Then several examples of current research projects are examined in some detail, namely, the Cambridge Distributed Computing System, Amoeba, V, and Eden.

Parallel Computing, 2002

Present operating systems are not built to support parallel computing--they do not provide services to manage parallelism, i.e., to globally manage parallel processes and computational resources. The cluster operating environments that are used to assist the execution of parallel applications do not provide support for both programming paradigms, message passing (MP) or distributed shared memory (DSM)--they are mainly offered as separate components implemented at the user level as library and independent server processes. Due to poor operating systems users must deal with clusters as a set of independent computers rather than to see this cluster as a single powerful computer. A single system image (SSI) of the cluster is not offered to users. There is a need for an operating system for clusters. We claim and demonstrate in this paper that it is possible to develop a cluster operating system that is able to efficiently manage parallelism; use cluster resources efficiently; support MP in the form of standard MP and PVM, and DSM; offer SSI; and make it easy to use. We show that to achieve these aims this operating system should inherit many features of a distributed operating system and provide new services which address the needs of parallel processes, cluster's resources, and application developers. In order to substantiate the claim the first version of a cluster operating system managing parallelism and offering SSI, called GENESIS, has been developed. Ó

IEEE Journal on Selected Areas in Communications, 2000

Ahstruct-This paper surveys some of the issues involved in building useful distributed systems involving PC's and hosts. Alternative communications techniques for micro-mainframe communication are compared. The point of view is presented that the PC user should be provided with a unified view of the heterogeneous distributed system to which he is connected. The proposed method is to formalize the notion of a service request and provide distributed services by function shipping service requests to remote nodes able to provide the service, e.g., personal computers will ship requests which they cannot satisfy locally to hosts on the network.

ACM SIGCOMM Computer Communication Review, 1987

The resource management system is designed to support location-transparent access to resources and to improve performance in a distributed internetwork environment. In this environment, access to one of several machines that have a given resource is determined by the effective bandwidth and reliability of internetwork communications, the ability to interact with the machines offering the resources, and the load on those machines. Using these criteria, the resources management system enables applications to determine and obtain access to the “best” copy of a resource. Should the resource become unavailable from one machine, the resource management system can dynamically direct the applications to another machine known to offer the same resource. This paper discusses some of the problems that motivated the design, an implementation for a UNIX workstation environment, and future directions for the resource management system .

A computer cluster is a group of linked computers, working together closely so that in many respects they form a single computer. The components of a cluster are commonly, but not always, connected to each other through fast local area networks. Clusters are usually deployed to improve performance and/or availability over that provided by a single computer, while typically being much more cost-effective than single computers of comparable speed or availability. The major objective in the cluster is utilizing a group of processing nodes so as to complete the assigned job in a minimum amount of time by working cooperatively. The main and vital strategy to achieve such objective is by transferring the extra loads from busy nodes to idle nodes. Network File System is a distributed file system protocol permit a client on a client computer to right of entry files over a network much like home storage is admittance. NFS, like many other protocols, builds on the Open Network Computing Remot...

Distributed File Systems (DFS), are systems used in both local network and wide area networks by using discs, storage areas and sources together. Nowadays, DFS makes possible operating big data, large-scale computings and transactions. The classifications are performed based on their working logics and architectures. These classifications were performed based on fault tolerance, replications, naming, synchronization and purpose of design. In this study, firstly the examinations on general design of DFSs were performed. Later, the results were discussed based on the advantages and disadvantages of Ceph and Hadoop and Network File Systems(NFS), commonly used in these days.

2000

We have implemented a software management tool-set which addresses the problems of compilation and distribution of software across multiple architectures in a mixed-vendor distributed environment. This package, which we call rtools, is made up of: a central database, a compilation tool, and a distribution tool. We describe the system in detail and look at possible implementations of rtools in other

Lecture Notes in Computer Science, 1994

Much computational power on state-of-the-art multicomputers like the Paragon is wasted with porting applications. Using networks of workstations is an attempt to withdraw this workload from multicomputer systems. Therefore an environment is needed which provides the programming interface of multicomputers on coupled workstations. The paper describes the design and implementation of the NXLib environment which allows to use Ethernet coupled workstations as a development platform for applications targeted for Intel Paragon systems.