Model-driven adaptation of Function-as-a-Service applications

Τσαγκαρόπουλος, Ανδρέας; Tsagkaropoulos, Andreas

dc.contributor.author	Τσαγκαρόπουλος, Ανδρέας
dc.contributor.author	Tsagkaropoulos, Andreas
dc.date.accessioned	2023-02-22T06:49:39Z
dc.date.available	2023-02-22T06:49:39Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/57155
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.24853
dc.rights	Αναφορά Δημιουργού-Όχι Παράγωγα Έργα 3.0 Ελλάδα	*
dc.rights.uri	http://creativecommons.org/licenses/by-nd/3.0/gr/	*
dc.subject	FaaS applications, Cloud Computing, Edge Computing, TOSCA, Severity	en
dc.subject	Εφαρμογές FaaS, Υπολογιστικό νέφος, Υπολογιστική άκρου, μοντέλα εφαρμογών, αναπροσαρμογή τοπολογίας	el
dc.title	Model-driven adaptation of Function-as-a-Service applications	en
dc.title	Αναπροσαρμογή Function-as-a-Service εφαρμογών βασισμένη σε μοντέλα	el
dc.contributor.department	Διοίκησης Πληροφοριακών Συστημάτων (IMU)	el
heal.type	doctoralThesis
heal.classification	Computer Engineering	el
heal.language	el
heal.language	en
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2022-04-04
heal.abstract	This doctoral dissertation is situated in the research field of FaaS processing, cloud topology adaptation and administration. It consists of an approach suggesting the definition of a cloud and edge processing topology using the TOSCA standard. Also, the presented approach includes a novel way of updating the processing topology based on the criteria set by the DevOps. Concerning the description of the applications, research on the most important works from the state of the art was carried out, focusing on contemporary generic application description languages. Also, the expressivity of these application description languages is briefly presented, and a comparison of the modelling extensions and approach suggested in this work was made against one of the most important and ubiquitous description languages (Terraform). Related to the adaptation of applications, research on the available adaptation methods was performed, and a new rule-based methodology suggesting the use of ‘Severity’ of the situation of a topology is described. Severity values are obtained by factoring in all of the dynamic metric values involved in a violated rule, and based on these a relevant adaptation action is suggested. The exploitation of Severity values using different algorithms (techniques) allows different ways of countering workloads. In the context of the aforementioned research four software systems were created, of which two are open-sourced. The first is related to the creation of application topology descriptions, leveraging the new TOSCA extensions. The remaining are related to analysis of Severity techniques and the creation of adaptation actions based on Severity techniques, although in two of them additional techniques which are widely used in the industry were also implemented. One of these systems is a simulator. Severity was proven to allow the definition of techniques leading to improved results, as these were determined by a chosen utility function. The experiments which were carried both in the level of simulations but also in a realistic testbed, indicate the need to make appropriate decisions on the technique which should be used based on the workload which is served. The successful use of Severity in the context of OpenFaas, a well-known and realistic FaaS platform, to perform the adaptation indicates the feasibility of the approach.	en
heal.advisorName	Μέντζας, Γρηγόριος
heal.committeeMemberName	Ψαρράς, Ιωάννης
heal.committeeMemberName	Μέντζας, Γρηγόριος
heal.committeeMemberName	Ασκούνης, Δημήτριος
heal.committeeMemberName	Αποστόλου, Δημήτριος
heal.committeeMemberName	Βεργινάδης, Ιωάννης
heal.committeeMemberName	Παπαθεοδώρου, Χρήστος
heal.committeeMemberName	Τσουμάκος, Δημήτριος
heal.academicPublisher	Σχολή Ηλεκτρολόγων Μηχανικών και Μηχανικών Υπολογιστών	el
heal.academicPublisherID	ntua
heal.numberOfPages	175
heal.fullTextAvailability	false