Serverless computing has become more popular and evolved to support more complex tasks than the original Function as a Service (FaaS) model. The design of serverless systems has advanced to accommodate application demands and offer flexibility. Careful characterization of modern serverless systems and understanding of current gaps are warranted. Publicly available datasets on workloads in select production serverless systems do not fully represent all offerings or capture traces at the required time resolution to identify changes in application-level request-response patterns.

Summary Verification of business processes typically relies on Petri net–based process models. While they allow for natural modeling and analysis of aspects such as parallelism and message exchange, such a process model is seldom complete and precise. This is mainly because the available techniques for deriving a Petri net model from the original model neglect process data in favor of feasible verification. In this paper, we present an approach for deriving more precise process models by leveraging a process‐to‐Petri‐net compiler, which takes as input a business process and generates as output a Petri net model for the process. This can be subsequently used for verification. However, in contrast to a conventional compiler, our compiler's objective is not to create the most efficient code but rather to produce a most precise but still effectively verifiable Petri net–based process model.

Although the areas of cloud computing and green IT are amongst the fastest growing markets in the IT industry, until now there are very few opportunities to combine the potential of both areas. In this paper, we present a method to combine the advantages of both to create standardized and energy efficient cloud services. For their description, we will use the emerging cloud computing standard TOSCA(OASIS, 2013). Thereby, it is possible to create standardized and model-based cloud applications which can be deployed in many cloud environments. We will further show how it is feasible to combine policies with TOSCA to realize energy-efficient management of cloud services. To accomplish this, we will provide ideas on how to extend the TOSCA language as well as the cloud operating environment in order to achieve the goal of portable, energy-efficient cloud services. The core of this work is the identification and integration of the underlying system architecture for a common solution concept. For this, the architectures and necessary adjustments are explained.

Formal methods, like Petri nets, provide a means to analyse BPEL processes, detecting weaknesses and errors in the process model already at design-time. However, in most approaches proposed so far, the analysis is restricted to the control flow only. Analysing quality properties of BPEL processes might therefore yield false-negative results. In this paper, we are presenting an enhanced BPEL to Petri net mapping, that incorporates relevant data aspects by doing a CSSA- based analysis and applying novel Petri net patterns. The resulting formal model allows for a more precise analysis of critical properties, such as controllability and behavioural compatibility.

WS-BPEL defines a standard for executable processes. Executable processes are business processes which can be automated through an IT infrastructure. The WS-BPEL specification also introduces the concept of abstract processes: In contrast to their executable siblings, abstract processes are not executable and can have parts where business logic is disguised. Nevertheless, the WS-BPEL specification introduces a notion of compatibility between such an under-specified abstract process and a fully specified executable one. Basically, this compatibility notion defines a set of syntactical rules that can be augmented or restricted by profiles. So far, there exist two of such profiles: the Abstract Process Profile for Observable Behavior and the Abstract Process Profile for Templates. None of these profiles defines a concept of behavioral equivalence. Therefore, both profiles are too strict with respect to the rules they impose when deciding whether an executable process is compatible to an abstract one. In this paper, we propose a novel profile that extends the existing Abstract Process Profile for Observable Behavior by defining a behavioral relationship. We also show that our novel profile allows for more flexibility when deciding whether an executable and an abstract process are compatible.

Metamodeling, object-orientation and formal methods are three promising ways to cope with the increasing size and complexity of today's software systems. Furthermore, effective control of development projects requires the use of versatile metrics for software size and complexity. We present a generic formal object-oriented metamodel (GM), specifically tailored for modeling object-oriented software systems, and use it as the foundation for defining two basic measures of structural quality: coupling and cohesion. Even though these two notions are generic, we restrict ourselves to defining them at the class level, which is probably the most useful for object-oriented systems. The metrics have a generic formal definition, which makes them simple, intuitive, and amenable to automated measurement.