{"title":"Beyond Sync: Distributed Temporal Coordination and Its Implementation in a Multi-Robot System","authors":"Agata Barciś, C. Bettstetter","doi":"10.1109/SASO.2019.00020","DOIUrl":"https://doi.org/10.1109/SASO.2019.00020","url":null,"abstract":"We propose a technique for adaptive temporal coordination in multi-agent systems where tasks have to be scheduled in a decentralized way. It provides three states: synchronized, splay, and clustered. Due to discretization in time and phase, the model operates with low signaling effort and is robust in the presence of delays. We analyze the model through simulations and demonstrate its feasibility through experiments with small robots.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122288496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ops-Scale: Scalable and Elastic Cloud Operations by a Functional Abstraction and Feedback Loops","authors":"Kamal Hakimzadeh, J. Dowling","doi":"10.1109/saso.2019.00017","DOIUrl":"https://doi.org/10.1109/saso.2019.00017","url":null,"abstract":"Recent research has proposed new techniques to streamline the autoscaling of cloud applications, but little effort has been made to advance configuration management (CM) systems for such elastic operations. Existing practices use CM systems, from the DevOps paradigm, to automate operations. However, these practices still require human intervention to program ad hoc procedures to fully automate reconfiguration. Moreover, even after careful programming of cloud operations, the backing models are insufficient for re-running such programs unchanged in other platforms—which implies an overhead in rewriting the programs. We argue that CM programs can be designed to be deployment-agnostic and highly elastic with well-defined abstractions. In this paper, we introduce our abstraction based on declarative functional programming, and we demonstrate it using a feedback loop control mechanism. Our proposal, called Ops-Scale, is a family of cloud operations that are derived by making a functional abstraction over existing configuration programs. The hypothesis in this paper is twofold: 1) it should be possible to make a highly declarative CM system rich enough to capture fine-grained reconfigurations of autoscaling automatically, and; 2) that a program written for a specific deployment can be re-used in other deployments. To test this hypothesis, we have implemented an open source configuration engine called Karamel that is already used in industry for large-scale cluster deployments. Results show that at scale Ops-Scale can capture a polynomial order of reconfiguration growth in a fully automated manner. In practice, recent deployments have demonstrated that Karamel can provision clusters of 100 virtual machines consisting of many-layers distributed services on Google's IaaS Cloud in 'less than 10 minutes'.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127696859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Distributed Self-Monitoring Sensor Networks Via Markov Switching Dynamic Linear Models","authors":"L. Fang, Juan Ye, S. Dobson","doi":"10.1109/SASO.2019.00014","DOIUrl":"https://doi.org/10.1109/SASO.2019.00014","url":null,"abstract":"Wireless sensor networks empowered with low-cost sensing devices and wireless communications present an opportunity to enable continuous, fine-grained data collection over a wide environment. However, the quality of data collected is susceptible to the hardware conditions and also adversarial external factors such as high variance in temperature and humidity. Over time, the sensors report erroneous readings, which deviate from true readings. To tackle the problem, we propose an efficient self-monitoring, self-managing and self-adaptive sensing framework based on a dynamic hybrid Bayesian network that combines Hidden Markov Model and Dynamic Linear Model. The framework does not only enable automatic on-line inference of true readings robustly but also monitor the working status of sensor nodes at the same time, which can uncover important insights on hardware management. The whole process also benefits from the derived approximation algorithm and thus supports on-line one-pass computation with minimum human intervention, which make the accurate formal inference affordable for distributed edge processing.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125036928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Generic Adaptive Monitoring Based on Executed Architecture Runtime Model Queries and Events","authors":"Thomas Brand, H. Giese","doi":"10.1109/SASO.2019.00012","DOIUrl":"https://doi.org/10.1109/SASO.2019.00012","url":null,"abstract":"Monitoring is a key functionality for automated decision making as it is performed by self-adaptive systems, too. Effective monitoring provides the relevant information on time. This can be achieved with exhaustive monitoring causing a high overhead consumption of economical and ecological resources. In contrast, our generic adaptive monitoring approach supports effectiveness with increased efficiency. Also, it adapts to changes regarding the information demand and the monitored system without additional configuration and software implementation effort. The approach observes the executions of runtime model queries and processes change events to determine the currently required monitoring configuration. In this paper we explicate different possibilities to use the approach and evaluate their characteristics regarding the phenomenon detection time and the monitoring effort. Our approach allows balancing between those two characteristics. This makes it an interesting option for the monitoring function of self-adaptive systems because for them usually very short-lived phenomena are not relevant.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"18 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123267986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Constructivist Approach to State Space Adaptation in Reinforcement Learning","authors":"Maxime Guériau, Nicolás Cardozo, Ivana Dusparic","doi":"10.1109/SASO.2019.00016","DOIUrl":"https://doi.org/10.1109/SASO.2019.00016","url":null,"abstract":"Reinforcement learning (RL) is increasingly used to achieve adaptive behaviours in Internet of Things systems relying on large amounts of sensor data. To address the need for self-adaptation in such environments, techniques for detecting environment changes and re-learning behaviours appropriate to those changes have been proposed. However, with the heterogeneity of sensor inputs, the problem of self-adaptation permeates one level deeper; in order for the learnt behaviour to adapt, the underlying environment representation needs to adapt first. The granularity of the RL state space might need to be adapted to learn more efficiently, or to match the new granularity of input data. This paper proposes an implementation of Constructivist RL (Con-RL), enabling RL to learn and continuously adapt its state space representations. We propose a Multi-Layer Growing Neural Gas (ML-GNG) technique, as an extension of the GNG clustering algorithm, to autonomously learn suitable state spaces based on sensor data and learnt actions at runtime. We also create and continuously update a repository of state spaces, selecting the most appropriate one to use at each time step. We evaluate Con-RL in two scenarios: the canonical RL mountain car single-agent scenario, and a large-scale multi-agent car and ride-sharing scenario. We demonstrate its ability to adapt to new sensor inputs, to increase the speed of learning through state space optimization, and to maintain stable long-term performance.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121673165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Knowledge Base K Models to Support Trade-Offs for Self-Adaptation using Markov Processes","authors":"L. H. Paucar, N. Bencomo","doi":"10.1109/SASO.2019.00011","DOIUrl":"https://doi.org/10.1109/SASO.2019.00011","url":null,"abstract":"Runtime models support decision-making and reasoning for self-adaptation based on both design-time knowledge and information that may emerge at runtime. In this paper, we demonstrate a novel use of Partially Observable Markov Decision Processes (POMDPs) as runtime models to support the decision-making of a Self Adaptive System (SAS) in the context of the MAPE-K loop. The trade-off between the non-functional requirements (NFRs) has been embodied as a POMDP in the context of the MAPE-K loop. Using Bayesian learning, the levels of satisficement of the NFRs are inferred and updated during execution in the form of runtime models in the Knowledge Base. We evaluate our work with a case study of the networking application domain.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124730838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Emergence of Division of Labor in Multi-Agent Systems","authors":"David W. King, Gilbert L. Peterson","doi":"10.1109/SASO.2019.00022","DOIUrl":"https://doi.org/10.1109/SASO.2019.00022","url":null,"abstract":"Division of labor in natural systems enables resiliency in times of dynamic change. Researchers have shown that division of labor can emerge in homogeneous populations predicated on the system's environment and the distribution of agent task bias. This article demonstrates that the emergence of division of labor in homogenous populations is also impacted by agent decision functions, agent population size, and environmental constraints. Results show, one, agent decision functions and population size have a significant impact on the division of labor scores, whereas, the influence of environmental constraints depends upon the chosen agent decision function. Two, results indicate that high division of labor scores do not necessarily translate to higher resource production, which, again, appears tied to agent decision functions. Three, although agent population size possesses a positive correlation to division of labor scores, agent decision functions play a more critical role in its emergence.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122156840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Title Page i","authors":"","doi":"10.1109/saso.2019.00001","DOIUrl":"https://doi.org/10.1109/saso.2019.00001","url":null,"abstract":"","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117199714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vladimir Podolskiy, Michael Mayo, Abigail M. Y. Koay, M. Gerndt, Panos Patros
{"title":"Maintaining SLOs of Cloud-Native Applications Via Self-Adaptive Resource Sharing","authors":"Vladimir Podolskiy, Michael Mayo, Abigail M. Y. Koay, M. Gerndt, Panos Patros","doi":"10.1109/SASO.2019.00018","DOIUrl":"https://doi.org/10.1109/SASO.2019.00018","url":null,"abstract":"With changing workloads, cloud service providers can leverage vertical container scaling (adding/removing resources) so that Service Level Objective (SLO) violations are minimized and spare resources are maximized. In this paper, we investigate a solution to the self-adaptive problem of vertical elasticity for co-located containerized applications. First, the system learns performance models that relate SLOs to workload, resource limits and service level indicators. Second, it derives limits that meet SLOs and minimize resource consumption via a combination of optimization and restricted brute-force search. Third, it vertically scales containers based on the derived limits. We evaluated our technique on a Kubernetes private cloud of 8 nodes with three deployed applications. The results registered two SLO violations out of 16 validation tests; acceptably low derivation times facilitate realistic deployment. Violations are primarily attributed to application specifics, such as garbage collection, which require further research to be circumvented.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126711468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multi-Scale Feedbacks for Large-Scale Coordination in Self-Systems","authors":"A. Diaconescu, L. Felice, P. Mellodge","doi":"10.1109/SASO.2019.00025","DOIUrl":"https://doi.org/10.1109/SASO.2019.00025","url":null,"abstract":"Multi-scale structures, or hierarchies, are prevalent in large-scale dynamic systems, from inert matter to living and artificial systems, and systems-of-systems. Yet, a general theory helping to understand and develop multi-scale systems is still missing. This paper identifies common design aspects and variants, and synthesises them via a novel design pattern - Multi-Scale Feedbacks - to help adaptive coordination in large-scale systems. It also suggests relations between design choices and qualitative properties. The proposed pattern was distilled from a cross-domain study, including particle physics, molecular biology, neuroscience, insect and human organisations, ecosystems, autonomous control and systems-of-systems.","PeriodicalId":259990,"journal":{"name":"2019 IEEE 13th International Conference on Self-Adaptive and Self-Organizing Systems (SASO)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125980885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}