Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
OFFLINE SCHEDULING OF TASK SETS WITH COMPLEX END-TO-END DELAY CONSTRAINTS
Mälardalen University, School of Innovation, Design and Engineering.
2017 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Software systems in the automotive domain are generally safety critical and subject to strict timing requirements. Systems of this character are often constructed utilizing periodically executed tasks, that have a hard deadline. In addition, these systems may have additional deadlines that can be specified on cause-effect chains, or simply task chains. They are defined by existing tasks in the system, hence the chains are not stand alone additions to the system. Each chain provide an end-to-end timing constraint targeting the propagation of data through the chain of tasks. These constraints specify the additional timing requirements that need to be fulfilled, when searching for a valid schedule. In this thesis, an offline non-preemptive scheduling method is presented, designed for single core systems. The scheduling problem is defined and formulated utilizing Constraint Programming. In addition, to ensure that end-to-end timing requirements are met, job-level dependencies are considered during the schedule generation. Utilizing this approach can guarantee that individual task periods along with end-to-end timing requirements are always met, if a schedule exists. The results show a good increase in schedulability ratio when utilizing job-level dependencies compared to the case where job-level dependencies are not specified. When the system utilization increases this improvement is even greater. Depending on the system size and complexity the improvement can vary, but in many cases it is more than double. The scheduling generation is also performed within a reasonable time frame. This would be a good benefit during the development process of a system, since it allows fast verification when changes are made to the system. Further, the thesis provide an overview of the entire process, starting from a system model and ending at a fully functional schedule executing on a hardware platform.

Place, publisher, year, edition, pages
2017. , p. 64
Keyword [en]
Embedded Systems, Offline Scheduling, End-to-End Delay, Constraint Programming, Job-level Dependencies, Automotive, Hard real-time systems
National Category
Embedded Systems
Identifiers
URN: urn:nbn:se:mdh:diva-35694OAI: oai:DiVA.org:mdh-35694DiVA, id: diva2:1108390
Subject / course
Computer Science
Supervisors
Examiners
Available from: 2017-10-17 Created: 2017-06-12 Last updated: 2017-10-17Bibliographically approved

Open Access in DiVA

fulltext(1475 kB)41 downloads
File information
File name FULLTEXT01.pdfFile size 1475 kBChecksum SHA-512
8ebf8d972039958308e1e379c16355e3b1792afc3a8dbe57d5c3f4458ad3621b7af4538575cf6220ac596a75da6fab6b5eba1915c6466bae6e80f06f42879af0
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Holmberg, Jonas
By organisation
School of Innovation, Design and Engineering
Embedded Systems

Search outside of DiVA

GoogleGoogle Scholar
Total: 41 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 60 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf