Cfetool: A General Purpose Tool for Anomaly Detection in Periodic Data

Cfengine’s environment daemon “cfenv ” has a limited and fixed set of metrics it measures on a computer. The data is assumed to be periodic in nature and cfenvd reports any data points that fall too far out of the pattern it has learned from past measurements. This is used to detect “anomalies ” on computers. We introduce a new standalone tool, “cfetool”, that allows arbitrary periodic data to be stored and evaluated. The user interface is modeled after rrdtool, another widely used tool to store measured data. Because a standalone tool can be used not only for computer related data, we have extended the built-in mathematics to apply to yearly data as well. 1

Sorting on a Massively Parallel System Using a Library of Basic Primitives: Modeling and Experimental Results

We present a comparative study of implementations of the following sorting algorithms on the Parsytec SC320 reconfigurable, asynchronous, massively parallel MIMD machine: Bitonic Sort, Odd-Even Merge Sort, Odd-Even Merge Sort with guarded split&merge, Periodic Balanced Sort, Columnsort, and two variants of Samplesort. The experiments are performed on 2- up to 5-dimensional wrapped butterfly networks with 8 up to 160 processors. We make use of library functions that provide primitives for global variables and synchronization, and we show that it is possible to implement efficient and portable programs easily. We assume that the time for accessing a global variable is linear in the parameters s, d, and c, where s is the size of the variable, d the distance between the accessing processor and the processor holding the variable, and c the contention, i. e., the number of processors accessing the variable simultaneously. Therefore, to predict the performance, we model the runtime of this ac..

OCCAM-light -- A multiparadigm programming language for Transputer networks

Two different paradigms for parallel computers are currently used. In the first one, called parallel computer networks or networks for short, processors communicate by neighbour-toneighbour message passing via a network, typically working asynchronously. The second on

A Realistic Cost Model for the Communication Time in Parallel Programs

. In this paper we develop a model for communication time on parallel computers consisting of processors and a service network, i.e., a network performing services like broadcast, synchronization, and global variables. The implementation of the service network is done on a free configurable Transputer network. Our cost model describes the communication time of accesses to global variables and consists of a multi-linear function. The cost model includes the parameters packet size, send hot spot, and the number of processors accessing global variables. These parameters influence the communication time in a high degree and capture important parameters like contention. We implement a Bitonic Sort and a Connected Components algorithm (among others) and we show that our model is able to predict the communication time within a 10 % error if indirect service networks are used. The applications show that it is easy for a programmer to determine the parameter values for our model and that our ne..