Anne Koziolek

Karlsruhe Institute of Technology | KIT · KASTEL – Institute of Information Security and Dependability

Data streaming applications are an important class of data-intensive systems and performance is an essential quality of such systems. Current component-based performance prediction approaches are not sufficient for modeling and predicting the performance of those systems, because the models require elaborate manual engineering to approximate the be...

Microservice architectures that use Message-oriented Middleware (MOM) have recently seen considerable evolution regarding extensibility, re-usability and maintainability. Of particular interest are systems that are distributed and deployed with mixed-technologies. On the one hand, such MOM-based microservice systems improve flexibility through thei...

With the increasing demand for customized systems and rapidly evolving technology, software engineering faces many challenges. A particular challenge is the development and maintenance of systems that are highly variable both in space (concurrent variations of the system at one point in time) and time (sequential variations of the system, due to it...

We present a new neural network architecture, called NaturalNet, which uses a simplified biological neuron model and consists of a set of nonlinear ordinary differential equations. We model the membrane potential of each neuron by integrating the in-flowing currents, but we do not consider ion channels, nor individual spikes. To keep the membrane p...

Software Architecture Documentation often consists of different artifacts. On the one hand, there is informal textual documentation. On the other hand, there are formal models of the system. Finding related information in multiple artifacts with different level of formality is often not easy. Therefore, trace links between these can help to underst...

The interest of girls in computing drops early during primary and secondary education, with minimal recovery in later education stages. In combination with the growing shortage of qualified computer science personnel, this is becoming a major issue, and also a target of numerous studies that examine measures, interventions, and strategies to boost...

Short development times of software became crucial to stay competitive. However, the quality should not suffer from the faster development processes, which is why increasingly more automation is gaining ground in this context. If models are involved in the development process and used for performance prediction, there are delays due to emerging inc...

Classifying requirements is crucial for automatically handling natural language requirements. The performance of existing automatic classification approaches diminishes when applied to unseen projects because requirements usually vary in wording and style. The main problem is poor generalization. We propose NoRBERT that fine-tunes BERT, a language...

Model-based performance prediction in agile software development promises to evaluate design alternatives and to reduce the cost of performance tests. To minimize the differences between a real software and its performance model, parametric dependencies are introduced. They express how the performance model parameters (such as loop iteration count,...

Data streaming applications are an important class of data-intensive systems. Performance is an essential quality of such systems. It is, for example, expressed by the delay of analysis results or the utilization of system resources. Architecture-level decisions such as the configuration of sources, sinks and operations, their deployment or the cho...

Quality-driven design decisions are often addressed by using architectural tactics that are re-usable solution options for certain quality concerns. Creating traceability links for these tactics is useful but costly. Automating the creation of these links can help reduce costs but is challenging as simple structural analyses only yield limited resu...

Architecture-based Performance Prediction (AbPP) allows evaluation of the performance of systems and to answer what-if questions without measurements for all alternatives. A difficulty when creating models is that Performance Model Parameters (PMPs, such as resource demands, loop iteration numbers and branch probabilities) depend on various influen...

Organizing professional conferences online has never been more timely. Responding to the new challenges raised by COVID-19, the organizers of the ACM/SPEC International Conference on Performance Engineering 2020 had to address the question: How should we organize these conferences online? This article summarizes their successful answer.

This article introduces a conceptual reference framework – the Models and Data (MODA) framework – to support a data-centric and model-driven approach for the integration of heterogeneous models and their respective data for the entire life-cycle of socio-technical systems. A pre-print version is available at https://hal.inria.fr/hal-02612087

Architecture-based Performance Prediction (AbPP) allows evaluation of the performance of systems and to answer what-if questions without measurements for all alternatives. A difficulty when creating models is that Performance Model Parameters (PMPs, such as resource demands, loop iteration numbers and branch probabilities) depend on various influen...

This book constitutes the refereed proceedings of the tracks and workshops which complemented the 14th European Conference on Software Architecture, ECSA 2020, held in L'Aquila, Italy*, in September 2020. The 30 full papers and 9 short papers presented in this volume were carefully reviewed and selected from 72 submissions. Papers presented were a...

Effectively managing variability in space and time is among the main challenges of developing and maintaining large-scale yet long-living software-intensive systems. Over the last decades, two large research fields, Software Configuration Management (SCM) and Software Product Line Engineering (SPLE), have focused on version management and the syste...

In modern software development processes, existing software components are increasingly used to implement functionality instead of developing it from scratch. Reuse of individual components or even more complex subsystems leads to more cost-efficient development and higher quality of software. Subsystems often offer a variety of features whose use...

In contrast to other engineering disciplines, software engineering lacks an understanding of the impact of design decisions on system quality properties as well as common standards and community case studies for comparing and evaluating research methods and results. In this paper, we address these shortcomings by offering infrastructure for modelin...

Battery systems can reduce the peak electrical consumption through proper charging and discharging strategies. To this end, consumers often rely on historic consumption data to select a cost-efficient battery system. However, historic data is an imperfect mapping of the real consumption, because of a coarse sampling rate or measurement inaccuracies...

One of the most common usage scenarios for Cloud-IoT applications is Sensing-as-a-Service, which focuses on the processing of sensor data in order to make it available for other applications. Auto-scaling is a popular runtime management technique for cloud applications to cope with a varying resource demand by provisioning resources in an autonomou...

Model-based approaches in Software Performance Engineering (SPE) are used in early design phases to evaluate performance. Most current model-based prediction approaches work quite well for single-core CPUs but are not suitable or precise enough for multicore environments. This is because they only consider a single metric (i.e., the CPU speed) as a...

The amount of data to be processed by experiments in high energy physics (HEP) will increase tremendously in the coming years. To cope with this increasing load, most efficient usage of the resources is mandatory. Furthermore, the computing resources for user jobs in HEP will be increasingly distributed and heterogeneous, resulting in more difficul...

Even after years of systematic support to achieve equal opportunity of women, the number of women in informatics education and research in Germany is still too low. In this paper, we describe the equal opportunity concept that we developed for a coordinated research effort proposal. We first explore and describe the situation of women in computing...

The development of software-intensive systems, such as automotive systems, is becoming more and more complex. To cope with this complexity, the developers use several modelling formalisms and languages to describe the same system from different viewpoints at multiple levels of abstraction. The used heterogeneous models can share common semantics an...

Applying model-based performance prediction requires that an up-to-date Performance Model (PM) is available throughout the development process. Creating such a model manually is an expensive process that is unsuitable for agile software development aiming to produce rapid releases in short cycles. Existing approaches automate the extraction of a PM...

Infrastructure as a Service (IaaS) Cloud services allow users to deploy distributed applications in a virtualized environment without having to customize their applications to a specific Platform as a Service (PaaS) stack. It is common practice to host multiple Virtual Machines (VMs) on the same server to save resources. Traditionally, IaaS data ce...

Infrastructure as a Service (IaaS) Cloud services allow users to deploy distributed applications in a virtualized environment without having to customize their applications to a specific Platform as a Service (PaaS) stack. It is common practice to host multiple Virtual Machines (VMs) on the same server to save resources. Traditionally, IaaS data ce...

The quality of modern industrial plants depends on the quality of the hardware used, as well as software. While the impact on quality is comparably well understood by making decisions about the choice of hardware components, this is less true for the decisions on software components. The quality of the resulting software system is strongly influenc...

In early design phases and during software evolution, design-time energy efficiency analyses enable software architects to reason on the effect of design decisions on energy efficiency. Energy efficiency analyses rely on accurate power models to estimate power consumption. Deriving power models that are both accurate and usable for design time pred...

This chapter defines three reference scenarios to which other chapters may refer for the purpose of motivating and illustrating architectures, techniques, and methods consistently throughout the book. The reference scenarios cover a broad set of characteristics and issues that one may encounter in self-aware systems and represent a range of domains...

This chapter discusses the importance of assessing self-awareness of a system and different approaches and aspects on how to enable a human as well as a machine to perform such an assessment. The chapter also elaborates on the different requirements and constraints for an assessment. Furthermore, this chapter outlines how these requirements and con...

One important issue in software engineering is to find an effective way to deal with the increasing complexity of software computing system. Modern software applications have evolved in terms of size and scope. Specific tools have been created to predict the Quality of Service (QoS) at design-time. However, the optimization of an architecture usual...

Too often, software designers lack an understanding of the effect of design decisions on such quality attributes as performance and reliability. This necessitates costly trial-and-error testing cycles, delaying or complicating rollout. This book presents a new, quantitative architecture simulation approach to software design, which allows software...

The reliability of power grids has been subject of study for the past few decades. Traditionally, detailed models are used to assess how the system behaves after failures. Such models, based on power flow analysis and detailed simulations, yield accurate characterizations of the system under study. However, they fall short on scalability. In this p...

In this chapter, we present a novel state space exploration method for distribution automation power grids built on top of an analytical survivability model. Our survivability model-based approach enables efficient state space exploration in a principled way using random-greedy heuristic strategies. The proposed heuristic strategies aim to maximize...

Activities related to software requirements engineering and software architecture significantly contribute to the success of software development projects. In software engineering practice, requirements and architecture affect each other and should not be treated in isolation. However, from a research and conceptual perspective, the dependencies be...

Due to hostile environments, space systems are equipped with hardware redundancies to guarantee proper operation. For reconfigurations beyond redundancies, manual decision making is needed, which results in down times, communication efforts and man hours in maintenance phases. We investigate automated reconfiguration decision support that determine...

Design-time quality analysis of software architectures evaluates the impact of design decisions in quality dimensions such as performance. Architectural design decisions decisively impact the energy efficiency (EE) of software systems. Low EE not only results in higher operational cost due to power consumption. It indirectly necessitates additional...

DevOps is a trend towards a tighter integration between development (Dev) and operations (Ops) teams. The need for such an integration is driven by the requirement to continuously adapt enterprise applications (EAs) to changes in the business environment. As of today, DevOps concepts have been primarily introduced to ensure a constant flow of featu...

Modern software development is typically performed by composing a software system from building blocks. The component-based paradigm has many advantages. However, security quality attributes of the overall architecture often remain unspecified and therefore, these cannot be considered when comparing several architecture alternatives. In this paper,...

Updating the requirements specification when software systems evolve is a manual task that is expensive and time consuming. Therefore, maintainers usually apply the changes to the code directly and leave the requirements unchanged. This results in the requirements rapidly becoming obsolete and useless. In this paper, we propose an approach that sup...

This paper discusses the challenges and opportunities of Software Performance Engineering (SPE) research in smartgrid (SG) environments. We envision to use SPE techniques to optimise the quality of information and communications technology (ICT) applications, and thus optimise the quality of the overall SG. The overall process of Monitoring, Analys...

Next generation IT infrastructures are highly driven by virtualization technology. The latter enables flexible and efficient resource sharing allowing to improve system agility and reduce costs for IT services. Due to the sharing of resources and the increasing requirements of modern applications on I/O processing, the performance of storage system...

The infrastructures used in cities to supply power, water and gas are consistently becoming more automated. As society depends critically on these cyber-physical infrastructures, their survivability assessment deserves more attention. In this overview, we first touch upon a taxonomy on survivability of cyber-physical infrastructures, before we focu...

We present models and metrics for the survivability assessment of distribution power grid networks accounting for the impact of multiple failures due to large storms. The analytical models used to compute the proposed metrics are built on top of three design principles: state space factorization, state aggregation, and initial state conditioning. U...

Antipatterns are conceptually similar to patterns in that they document recurring solutions to common design problems. Software Performance Antipatterns document common performance problems in the design as well as their solutions. The definition of performance antipatterns concerns software properties that can include static, dynamic, and deployme...

Smart grids are fostering a paradigm shift in the realm of power distribution systems. Whereas traditionally different components of the power distribution system have been provided and analyzed by different teams through different lenses, smart grids require a unified and holistic approach that takes into consideration the interplay of communicati...

To meet end-user performance expectations, precise performance requirements are needed during development and testing, e.g., to conduct detailed performance and load tests. However, in practice, several factors complicate performance requirements elicitation: lacking skills in performance requirements engineering, outdated or unavailable functional...

During the last decade, researchers have proposed a number of model transformations enabling performance predictions. These transformations map performance-annotated software architecture models into stochastic models solved by analytical means or by simulation. However, so far, a detailed quantitative evaluation of the accuracy and efficiency of d...

Design decisions for complex, component-based systems impact multiple quality of service (QoS) properties. Often, means to improve one quality property deteriorate another one. In this scenario, selecting a good solution with respect to a single quality attribute can lead to unacceptable results with respect to the other quality attributes. A promi...

Requirements are usually one of the main drivers for software architecture. Although current research acknowledges the opposite effects of design decisions on requirements engineering, it does not go beyond the general idea of their existence. The contribution of this paper lies in the explicit discussion of the effects of design decisions on requi...

The 2nd International Workshop on Software Engineering Challenges for the Smart Grid focuses on understanding and identifying the unique challenges and opportunities for SE to contribute to and enhance the design and development of the smart grid. In smart grids, the geographical scale, requirements on real-time performance and reliability, and div...

Model-based performance prediction methods aim at evaluating the expected response time, throughput, and resource utilization of a software system at design time, before implementation, to achieve predictability of the system’s performance characteristics. Existing performance prediction methods use monolithic, throw-away prediction models or compo...

Smart grids are fostering a paradigm shift in the realm of power distribution systems. Whereas traditionally different components of the power distribution system have been provided and analyzed by different teams through different lenses, smart grids require a unified and holistic approach that takes into consideration the interplay of communicati...

Smart grids are fostering a paradigm shift in the realm of power distribution systems. Whereas traditionally different components of the power distribution system have been provided and analyzed by different teams, smart grids require a unified and holistic approach taking into consideration the interplay of distributed generation, distribution aut...

Today, software systems are more and more executed in dynamic, virtualized environments. These environments host diverse applications of different parties, sharing the underlying resources. The goal of this resource sharing is to utilize resources efficiently while ensuring that quality-of-service requirements are continuously satisfied. In such sc...

Keeping requirements specifications up-to-date when systems evolve is a manual and expensive task. Software engineers have to go through the whole requirements document and look for the requirements that are affected by a change. Consequently, engineers usually apply changes to the implementation directly and leave requirements unchanged. In this p...