Hybrid performance modeling and prediction of large-scale computing systems

Performance is a key feature of large-scale computing systems. However, the achieved performance when a certain program is executed is significantly lower than the maximal theoretical performance of the large-scale computing system. The model-based performance evaluation may be used to support the performance-oriented program development for large-scale computing systems. In this paper we present a hybrid approach for performance modeling and prediction of parallel and distributed computing systems, which combines mathematical modeling and discrete-event simulation. We use mathematical modeling to develop parameterized performance models for components of the system. Thereafter, we use discrete-event simulation to describe the structure of system and the interaction among its components. As a result, we obtain a high-level performance model, which combines the evaluation speed of mathematical models with the structure awareness and fidelity of the simulation model. We evaluate empirically our approach with a real-world material science program that comprises more than 15,000 lines of codePeer ReviewedPostprint (published version

A Study on the Parallelization of Terrain-Covering Ant Robots Simulations

Agent-based simulation is used as a tool for supporting (time-critical) decision making in differentiated contexts. Hence, techniques for speeding up the execution of agent-based models, such as Parallel Discrete Event Simulation (PDES), are of great relevance/benefit. On the other hand, parallelism entails that the final output provided by the simulator should closely match the one provided by a traditional sequential run. This is not obvious given that, for performance and efficiency reasons, parallel simulation engines do not allow the evaluation of global predicates on the simulation model evolution with arbitrary time-granularity along the simulation time-Axis. In this article we present a study on the effects of parallelization of agent-based simulations, focusing on complementary aspects such as performance and reliability of the provided simulation output. We target Terrain Covering Ant Robots (TCAR) simulations, which are useful in rescue scenarios to determine how many agents (i.e., robots) should be used to completely explore a certain terrain for possible victims within a given time. © 2014 Springer-Verlag Berlin Heidelberg

A performance analysis tool of discrete-events systems

The analysis of the logic correctness of the system and its performance evaluation are usually carried out using, respectively, the Petri nets formalism and the discrete-event simulation. Several tools exist for both. The Platform Independent Petri Net Editor (PIPE) is a free software tool developed in Java for the modelling, simulation and qualitative analysis of Petri nets. It has been designed with an open philosophy so that extensions can be easily incorporated. SIMAN is one of the first discrete-event simulation languages developed. It has extensively proven its power. This paper first presents a module for the PIPE software that allows the automatic generation of SIMAN code from a Petri net. Then, a tool is proposed to aid the performance analysis of manufacturing systems from its SIMAN model. These tools are designed as a support for students in the understanding of the simulation methodology

Performance modelling of applications in a smart environment

PhD ThesisIn today’s world, advanced computing technology has been widely used to improve our living conditions and facilitate people’s daily activities. Smart environment technology, including kinds of smart devices and intelligent systems, is now being researched to provide an advanced intelligent life, easy, comfortable environment. This thesis is aimed to investigate several related technologies corresponding to the design of a smart environment. Meanwhile, this thesis also explores different modelling approaches including formal methods and discrete event simulation. The core contents of the thesis include performance evaluation of scheduling policies and capacity planning strategies. The main contribution is in developing a modelling approach for smart hospital environments. This thesis also provides valuable experience in the formal modelling and the simulation of large scale systems. The chief findings are that the dynamic scheduling policy is proved to be the most efficient approach in the scheduling process; and a capacity scheme is also verified as the optimal scheme to obtain the high work efficiency under the condition of limited human resource. The main methods used for the performance modelling are Performance Evaluation Process Algebra (PEPA) and discrete event simulation. A great deal of modelling tasks was completed with these methods. For the analysis, we adopt both numerical analysis based on PEPA models and statistical measurements in the simulation

JMT – Performance Engineering Tools for System Modeling

We present the Java Modelling Tools (JMT) suite, an integrated framework of Java tools for performance evaluation of computer systems using queueing models. The suite offers a rich user interface that simplifies the definition of performance models by means of wizard dialogs and of a graphical design workspace. The performance evaluation features of JMT span a wide range of state-of-the-art methodologies including discrete-event simulation, mean value analysis of product-form networks, analytical identification of bottleneck resources in multiclass environments, and workload characterization with fuzzy clustering. The discrete-event simulator supports several advanced modeling features such as finite capacity regions, load-dependent service times, bursty processes, fork-and-join nodes, and implements spectral estimation for analysis of simulative results. The suite is open-source, released under the GNU general public license (GPL), and it is available for free download at http://jmt.sourceforge.net

Discrete Simulation of Distributed Systems - Performance Evaluation of a Notification Channel Federation

This paper presents how discrete simulation can be used for performance evaluation of distributed systems. With this methodology it is not needed to implement the system itself, only a model of proper specification is required. Simulation models for distributed systems can be easily adopted from other models which are already used in network simulations with good results. The tool that supports our measurements is a powerful telecom simulation platform, a simulations development environment that supports object-oriented programming. The model used for demonstration represents a notification channel federation including an arbitrary number of event suppliers and event consumers connected to a scalable network. Performance is evaluated for various configurations, and results are presented

A process algebra based simulation model of a Diagnostic Radiology Department

In the last years, it's possible to observe a growing interest in applying in the health care sector tools and methods, which have been successfully applied in other service and industry sectors and have helped to improve planning and efficient use of resources, while maintaining high quality of the delivered service or product. Discrete event simulation represents a powerful and proven tool, which enables the experimentation of several possible solutions at relatively low cost. This paper is focused on the modeling and analysis of a Diagnostic Radiology Department (DRD) in an important Southern Italy hospital and adopts a discrete-event simulation approach based on a process algebra dialect, called $. Some "scenario" results are then illustrated in order to derive basic performance indicators of the system, which could be useful to hospital decision-makers and constitute a starting point for a deeper cost-benefit evaluation

Simulation study of routing protocols in wireless sensor networks

Wireless sensor networks, a distributed network of sensor nodes perform critical tasks in many application areas such as target tracking in military applications, detection of catastrophic events, environment monitoring, health applications etc. The routing protocols developed for these distributed sensor networks need to be energy efficient and scalable. To create a better understanding of the performance of various routing protocols proposed it is very important to perform a detailed analysis of them. Network simulators enable us to study the performance and behavior of these protocols on various network topologies. Many Sensor Network frameworks were developed to explore both the networking issues and the distributed computing aspects of wireless sensor networks. The current work of simulation study of routing protocols is done on SensorSimulator, a discrete event simulation framework developed at Sensor Networks Research Laboratory, LSU and on a popular event driven network simulator ns2 developed at UC Berkeley. SensorSimulator is a discrete event simulation framework for sensor networks built over OMNeT++ (Objective Modular Network Test-bed in C++). This framework allows the user to debug and test software for distributed sensor networks. SensorSimulator allows developers and researchers in the area of Sensor Networks to investigate topological, phenomenological, networking, robustness and scaling issues, to explore arbitrary algorithms for distributed sensors, and to defeat those algorithms through simulated failure. The framework has modules for all the layers of a Sensor Network Protocol stack. This thesis is focused on the simulation and performance evaluation of various routing protocols on SensorSimulator and ns2. The performance of the simulator is validated with a comparative study of Directed Diffusion Routing Protocol on both ns2 and SensorSimulator. Then the simulations are done to evaluate the performance of Optimized Broadcast Protocols for Sensor Networks, Efficient Coordination Protocol for Wireless Sensor Networks on SensorSimulator. Also a performance study of Random Asynchronous Wakeup protocol for Sensor Networks is done on ns2