Engineering Commons^™

Chimera Ii : A Real-Time Unix-Compatible Multiprocessor Operating System For Sensor-Based Control Applications, David B. Stewart, Donald Schmitz, Pradeep K. Khosla

Pradeep K Khosla

Abstract: "This paper describes the CHIMERA II multiprocessing operating system, which has been developed to provide the flexibility, performance, and UNIX-compatible interface needed for fast development and implementation of parallel real-time control code. The operating system is intended for sensor-based control applications such as robotics, process control, and manufacturing. The features of CHIMERA II include support for multiple general purpose CPUs; support for multiple special purpose processors and I/O devices; a UNIX-like environment, which supports most standard C system and library calls; standardized interrupt and exception handlers; and a user interface which serves as a terminal interface to the executing …

What Is Rcu, Fundamentally?, Paul E. Mckenney, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Read-copy update (RCU) is a synchronization mechanism that was added to the Linux kernel in October of 2002. RCU achieves scalability improvements by allowing reads to occur concurrently with updates. In contrast with conventional locking primitives that ensure mutual exclusion among concurrent threads regardless of whether they be readers or updaters, or with reader-writer locks that allow concurrent reads but not in the presence of updates, RCU supports concurrency between a single updater and multiple readers. RCU ensures that reads are coherent by maintaining multiple versions of objects and ensuring that they are not freed up until all pre-existing read-side …

Content Aware Request Distribution For High Performance Web Service: A Performance Study, Robert M. Jones

Dissertations and Theses

The World Wide Web is becoming a basic infrastructure for a variety of services, and the increases in audience size and client network bandwidth create service demands that are outpacing server capacity. Web clusters are one solution to this need for high performance, highly available web server systems. We are interested in load distribution techniques, specifically Layer-7 algorithms that are content-aware. Layer-7 algorithms allow distribution control based on the specific content requested, which is advantageous for a system that offers highly heterogenous services. We examine the performance of the Client Aware Policy (CAP) on a Linux/Apache web cluster consisting of …

World Wide Graphics, Alysha Marie Timmons

Theses Digitization Project

The scope of this project describes World Wide Graphics (WWG) a software package that provides instructors with the tools needed to present a web-based presentation to a group of students while having the ability of enhancing the prepared HTML slide with userdrawn graphics and highlighting.

Spider: An Overview Of An Object-Oriented Distributed Computing System, Han-Sheng Yuh

Theses Digitization Project

The Spider Project is an object-oriented distributed system which provides a testbed for researchers in the Department of Computer Science, CSUSB, to conduct research on distributed systems.

A User-Level Process Package For Concurrent Computing, Ravi Konuru, Steve Otto, Jonathan Walpole, Robert Prouty, Jeremy Casas

Computer Science Faculty Publications and Presentations

A lightweight user-level process(ULP) package for parallel computing is described. Each ULP has its own register context, stack, data and heap space and communication with other ULPs is performed using locally synchronous, location transparent, message passing primitives. The aim of the package is to provide support for lightweight over-decomposition, optimized local communication and transparent dynamic migration. The package supports a subset of the Parallel Virtual Machine(PVM) interface[Sun90).

Porting Chorus To The Pa-Risc: Virtual Memory Manager, Jon Inouye, Marion Hakanson, Ravi Konuru, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This document describes the port ofthe Chorus virtual memory manager to the Hewlett-Packard Precision Architecture rusc (PA-RISC) workstation. The information contained in this paper will be of interest to people who:

• intend to port the Chorus virtual memory section. • intend to port a virtual memory design to the Hewlett-Packard PA-RISC.

The reader is strongly encouraged to read the following PA-Chorus documents before reading this document:

• Technical Report CSE-92-3, Porting Chorus to the PA-RISC: Project Overview

Porting The Chorus Supervisor And Related Low-Level Functions To The Pa-Risc, Ravi Konuru, Marion Hakanson, Jon Inouye, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This document is part of a series of reports describing the design decisions made in porting the Chorus Operating System to the Hewlett-Packard 9000 Series 800 workstation.

The Supervisor is the name given by Chorus to a collection of low-level functions that are machine dependent and have to be implemented when Chorus is ported from one machine to another. The Supervisor is responsible for interrupt, trap and exception handling, managing low-level thread initialization, context switch, kernel initialization, managing simple devices (timer and console) and offering a low-level debugger. This document describes the port of the Supervisor and related low-level functions. …