Benny Akesson

Senior Research Fellow @ TNO-ESI | Endowed Professor @ University of Amsterdam

Automatic Workload Inference Improves Scalability of DSE in Complex Systems

I am happy to announce that the paper “Automated Derivation of Application Workload Models for Design Space Exploration of Industrial Distributed Cyber-Physical Systems” has been accepted for publication at the 7th IEEE International Conference on Industrial Cyber-Physical Systems (ICPS). The paper is first-authored by Faezeh Saadatmand in the context of the DSE2.0 project, a part of the academic research program MasCot, co-funded by TNO-ESI and NWO. Congratulations Faezeh!

The paper addresses challenges with respect to designing their next-generation distributed cyber-physical systems (dCPS). Efficient Design Space Exploration (DSE) techniques are needed to evaluate possible design decisions and their consequences on non-functional aspects of the systems. To enable scalable and efficient DSE of complex dCPS, it is essential to have abstract and coarse-grained models that are both accurate and capable of capturing dynamic application workloads. However, manually creating such models is time-consuming and error-prone, and they need to be continuously updated as the system evolves. This research addresses this need by introducing an automatic method for deriving an application workload model. This model, based on trace analysis, captures computation and communication activities within an application in a timing-agnostic manner. The approach has been validated through a case study on an ASML Twinscan lithography machine, demonstrating high accuracy in capturing real application workloads. Next steps in this research involves combining this model with an automatically inferred hardware platform model to enable DSE exploring different hardware, software, and mapping alternatives.

The Journey from Offline to Online Conformance Checking for Microservice Applications

Ricardo Andrade has successfully defended his master thesis “Real-Time Conformance Checking for Microservice Applications“. This thesis was done in the context of the ArchViews project together with Thales. The academic supervisor was ESI colleague and TU/e professor Johan Lukkien and the daily supervision at ESI was done by myself and Ben Pronk.

The thesis addresses the shift from monolithic architectures to microservice architectures in order to manage the complexities and dependencies that emerge as systems grow and incorporate new features. A significant gap identified in the management of microservice applications is the lack of effective conformance checking techniques that can verify whether the execution of microservices aligns with their specification. To address this, the thesis proposes an innovative solution by developing an online conformance checker specifically designed for microservice applications. The project begins with the creation of an offline conformance checker that evaluates conformance using execution traces and sequence diagrams. The work then progresses to an online conformance checker, significantly improving performance and delivering conformance results within approximately 30 seconds per trace. This rapid response time meets the requirement for swift identification and correction of non-conforming sequences, thereby offering a practical and effective tool for managing microservice applications.

Ricardo presented his work very well using beautifully prepared slides. He confidently answered questions from the audience and the examination committee and left the session with a good grade. Ricardo is now moving on from his studies to start his career at CGI. We wish him the best of luck in his future career.

Jesse Liauw-A-Fong Defends Master’s Thesis on Local Anomaly Detection in Smart Public Transport Vehicles

Yesterday, Jesse Liauw-A-Fong, a student of the Master of Software Engineering program at UvA, defended his thesis Local Anomaly Detection in Smart Public Transport Vehicles. This research was conducted externally at a company called Ximedes. Jessie’s research is addressing the problem of detecting anomalies, such as a loss of cloud connection, in Smart Public Transport Vehicles (SPTV), such as buses, trams, and metros, comprising many complex heterogeneous systems. It emphasizes the importance of local, context-aware anomaly detection due to the dynamic nature of SPTVs and explores the generalization of anomaly detection, particularly addressing performance, normal region, and quality challenges. The research proposes a unified data collection framework comparing agent-based and agent-less methods, advocating for an agent-based approach for its adaptability and integration ease. It also quantitatively evaluates three local anomaly detection algorithms on real data from a specific bus line. We thank Jessie for his contributions to our research and wish him the best of luck in his future career.

MasCot Program: Bridging Academia and Industry for High-Tech Innovation in Bits & Chips Feature

An article about strategic academic programming at TNO-ESI has appeared in Bits & Chips. The MasCot program, a collaboration co-funded by ESI and the Dutch research council NWO, is designed to tackle the increasing complexity of high-tech equipment.  The program addresses the pressing need for advanced engineering methodologies through four projects covering essential topics, such as design space exploration during early system design, scheduling, verification, and restructuring of evolving software. In the article, I explain how the 3-million-euro program facilitates the transition of academic research into practical industrial applications, creating an innovation funnel that spans from academic research through applied research to industrial embedding. The program’s strategic approach not only mitigates the risks associated with high-reward, complex projects but also fosters a symbiotic relationship between academia, industry, and TNO, allowing for a continuous exchange of knowledge, challenges, and innovations.

Master Thesis Shines Light on Hardware Dimensioning for Cyber-Physical Systems

On Wednesday, Marijn Vollaard defended his master thesis “Hardware Dimensioning for Microservice-based Cyber-Physical Systems: A Profiling and Performance Prediction Method” at the University of Amsterdam. This research has been supervised by Ben Pronk and myself as a part of a project with TNO-ESI.

The thesis addresses the problem of determining the number of homogeneous compute nodes needed for a particular variant of a cyber-physical system to meet its timing requirements. This is important in early discussions with customers and bidding processes, since it affects the size and cost of the resulting system. To this end, the thesis proposes a structured hardware dimensioning methodology comprising a profiling method and a performance prediction method. The four novel contributions of the thesis are: 1) A component-based profiling method, 2) a performance prediction method, 3) a structured hardware dimensioning methodology, and 4) validation of the approach, using a case study that represents a prototype of a CPS. Experimental evaluations on the case study show that the predicted performance differs from measurements on the application by at most 20%, which is satisfactory for hardware dimensioning decisions for new product variants.

The defense went well and Marijn confidently presented his story and convincingly answered the questions of the audience. The examination committee, impressed by his work, awarded his thesis a well-deserved grade of 8. As we bid farewell to Marijn, embarking on his next career adventure, we also extend our heartfelt congratulations. He certainly has much to be proud of. We wish him all the best on his travels and in his future pursuits.

Mastering Complexity at ICT Open 2024

TNO-ESI is hosting a Mastering Complexity for Cyber-Physical Systems track at ICT Open 2024. The event will take place in Utrecht on April 10-11. My colleague Rosilde Corvino will be the track chair of this event, together with myself. Submit an abstract, poster, or demo now and share with the community how your work addresses the challenge of increasing complexity in cyber-physical systems. Contributions in areas including system architecting, system dependability, system evolvability, systems of systems, and system performance are welcome.

Call for abstracts, posters, and demos:
https://ictopen.nl/track-mastering-complexity-for-cyber-physical-systems-cpshttps://lnkd.in/enBaRjNZ

Submission link:
https://www.ictopen2024.nl/submit-an-abstract/https://lnkd.in/etghmm8F

Master’s Student Marijn Vollaard Shines with Study on Hardware Dimensioning for Microservice Applications in Cyber-Physical Systems

Our master’s student, Marijn Vollaard, has achieved a significant milestone by completing and presenting his literature study titled “Hardware Dimensioning for Microservice Applications in Cyber-Physical Systems: Current Directions and Challenges” The study addresses the challenge of dimensioning the number of compute nodes required to meet the performance demands of microservice-based applications in cyber-physical systems. It thoroughly reviews an extensive body of literature on application and system profiling, performance prediction, and design-space exploration to establish the current state of knowledge in this field. The survey culminates in a discussion about how the surveyed literature applies to microservice applications, the cyber-physical systems context, and the problem of hardware dimensioning. Overall, this is a nice piece of work with a lot of references presented in a systematic way. Congratulations to Marijn for his great effort!”

Master Thesis Tackles Architectural Anti-patterns in Microservice Applications

Today, we are delighted to announce the successful defense of the outstanding master’s thesis titled “Architectural Anti-Pattern Identification and Mitigation in Microservice Applications Based on Telemetry” by our master student, Amund Lunke Rohne from the University of Amsterdam. This master’s project was a collaborative effort involving TNO-ESI and Thales.

The thesis addresses the problem that microservices offer benefits like scalability and separation of concerns, but also introduce many complex service dependencies. The decomposition of microservice applications can impact system performance and maintainability and can lead to architectural anti-patterns over time. While simple anti-patterns can be detected using analysis of service dependencies, there is a lack of formal mathematical definitions which prevents more complex anti-patterns from being automatically detected by tools. The thesis introduces a novel model called Granular Hardware Utilization-Based Service Dependency Graph (GHUBS), a fine-grained model that captures the interactions dependencies between services at the level of individual requests. The GHUBS model can be manually specified in early design phases to validate a microservice decomposition, or automatically created using telemetry data from a running application. Mathematical formalizations are introduced for four common architectural anti-patterns and methods for automatically detecting them using the GHUBS model is presented. A method for recommending how to mitigate the identified anti-patterns based on the service dependencies in the GHUBS model, as well as resource utilization metrics for the services, is also presented. The approach is implemented in a tool called Televisor and validated through case studies on open-source microservice benchmarking applications, revealing instances of these anti-patterns.

We thank Amund for his work and a fruitful collaboration, and wish him the best of luck in his future career.

3rd Annual MasCot Program Day 2023 Focuses on Technology Transfer and Industry-Academia Collaboration

In a bid to spearhead advancements in engineering methodologies and manage the increasing complexity of industrial systems, the third annual Mastering Complexity (MasCot) Program Day was successfully held on Tuesday, October 10, 2023. The MasCot program, a six-year strategic academic initiative jointly funded by TNO-ESI and NWO, has brought together leading universities and research organizations to pioneer the next generation of engineering methods, promoting cost-effective and high-quality development of industrial systems. The program consists of four key projects: 1) Scheduling Adaptive Modular Flexible Manufacturing Systems (TU/e, TU Delft, Radboud University), 2) Programming and Validating Software Restructurings (TU Delft, TU/e), 3) Testing in Times of Continuous Change (Radboud University, Twente University), and 4) Design Space Exploration 2.0: Towards Optimal Design of Complex, Distributed Cyber Physical Systems (UvA, Leiden University).

This year, Radboud University hosted the event at Hotel Van der Valk Nijmegen-Lent, drawing a crowd of 38 attendees from academia, industry, NWO, and TNO-ESI. With the first MasCot projects set to conclude in 2024, the theme of this year's gathering revolved around technology transfer. The event commenced with project updates from each of the four projects. During breaks, attendees had the opportunity to engage in technical dialogues with PhD students, who presented their work on posters. A highlight of the day was the keynote address delivered by Sjoerd Verduyn Lunel, head of ASML research (a.i.). Verduyn. A key message of his presentation was the required improvement of productivity of design engineers by a factor of 2.5 in the next ten years to keep up the pace of innovation. ASML is therefore engaging in defining road maps and establishing long-term collaborations with academic partners and research organization, such as TNO. He also described how ASML are differentiating projects at different levels of maturity, from fundamental research to proofs-of-concept, and how they scale up and transfer knowledge between these phases. This keynote was well-appreciated and many participants were inspired by this structured approach to programming and managing research and innovation.

The afternoon was dedicated to breakout sessions where participants shared their perspectives on technology transfer and discussed the roles that various MasCot stakeholders—universities, industry, NWO, and ESI—can concretely play in facilitating this critical process. The day concluded with a networking session and dinner, marking another successful edition of the MasCot Program Day.

Prestigious Test Of Time Award at ESWEEK 2023 for Memory Controller Research

I am happy to announce that we received the Test Of Time Award for CODES+ISSS at ACM/IEEE Embedded Systems Week (ESWEEK) 2023 in Hamburg, Germany. The Test of Time Award is the most prestigious award of ESWEEK and honors the authors of papers of previous editions of the co-located conferences (CASES 2008, CODES+ISSS 2007, and EMSOFT 2007) that had the highest impact. We received this award for my first paper as a PhD student “Predator: a predictable SDRAM memory controller“, which written with co-authors Kees Goossens and Markus Ringhofer and published in CODES+ISSS 2007.

The paper addressed the problem of providing guarantees on bandwidth and latency to ports on an SDRAM memory controller, a key component of a system-on-chip. Previously, this was only done for statically scheduled memory controllers that assumed the workload of memory requests was known a priori. While this limitation was acceptable for simple systems, increasing integration of functionality in consumer electronics products like set-top boxes challenged this assumption, requiring more dynamic solutions. To this end, the paper presented concepts, hardware architecture, and performance analysis for a more dynamic SDRAM memory controller for real-time systems.

This work formed the base for my memory research, which evolved into a research line that would continue for over a decade and in which six PhD students eventually graduated. In total, this research resulted in a body of work of 30+ papers and two books, which together have been cited more than 2000 times. It also resulted in the open-source tool DRAMPower, which is used to estimate energy consumption of memories. This tool has been integrated in the popular Gem5 simulator and is widely used by the computer architecture community.

The paper was impactful because it was one of the first papers about memory controllers for real-time systems. More papers would follow from Barcelona Supercomputing Center, UC Berkley, and University of Waterloo. Step by step, the proposed memory controllers would become more dynamic and the analysis more sophisticated. This continued until the middle of the previous decade, at which the field moved more from proposing and analyzing new memory controller architectures for systems-on-chips to configuring and analyzing commercial-of-the-shelf memory controllers. This is still an active field of research in the real-time systems community today.

“Receiving this award is an unexpected honor, and I extend my heartfelt thanks to my co-authors and everyone that contributed to subsequent advancements in this field, in particular my former PhD students Karthik Chandrasekar, Manil Dev Gomony, Sven Goossens, Yonghui Li, and Anna Minaeva. Together, we created, developed, and matured the research field of memory controllers for real-time systems.”