Dependable Resource Sharing for Compositional Real-Time Systems

Abstract

Citation for published version (APA):Heuvel, van den, M. M. H. P., Bril, R. J., & Lukkien, J. J. (2011). Dependable resource sharing for compositional real-time systems. In Proceedings of the 17th IEEE International Conference on Embedded and Real-time Computing Systems and Applications (RTCSA 2011, Toyama, Japan, August 28-31, 2011 Please check the document version of this publication:• A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publicationGeneral rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal.If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement: www.tue.nl/taverne Take down policyIf you believe that this document breaches copyright please contact us at: openaccess@tue.nl providing details and we will investigate your claim. AbstractHierarchical scheduling frameworks (HSFs) have been extensively investigated as a paradigm for facilitating temporal isolation between components that need to be integrated on a single shared processor. In the presence of shared resources, however, temporal isolation may break when one of the accessing components executes longer than specified during global resource access. The ability to confine such temporal faults makes the HSF more dependable. As a solution we propose a stack-resource-policy (SRP)-based synchronization protocol for HSFs, named Hierarchical Synchronization protocol with Temporal Protection (HSTP).When a component exceeds its specified critical-section length, HSTP enforces a component to self-donate its own budget to accelerate the resource release. In addition, a component that blocks on a locked resource may donate budget. The schedulability of those components that are independent of the locked resource is unaffected. HSTP efficiently limits the propagation of temporal faults to resource-sharing components by disabling local preemptions in a component durin...

Performance evaluation of analysis methods for arbitrating non-preemptive resource access in compositional real-time systems

“…The improved OWP (IOWP) analysis in [14] made the results in [7] obsolete. Furthermore, van den Heuvel et al [14] have proven that SIRAP dominates ONP, no matter the system parameters.…”

“…Local fixed-priority scheduling: Secondly, we take the same steps for FPPS of tasks for which the next sufficient scheduling condition must be satisfied: (14) where rbf s pt,iq denotes the worst-case cumulative processor request of τ si for a time interval of length t.…”

“…The only difference between the analysis of SIRAP and ONP is the moment at which these additional reservations are made in the analysis: with ONP these X s time units are allocated to a component at the global analysis and with SIRAP these X s time units are allocated at the local analysis of a component. As concluded in [14], the ONP analysis can therefore be used as a conservative analysis for systems with critical sections arbitrated by SIRAP.…”

“…The smallest budget satisfying the local scheduling condition is the same for both deadline-monotonic scheduling as well as for EDF scheduling of tasks. Using the local scheduling condition in (14) and assuming dt ¥ 0 :: ibf Γ s ptq 0, we derive Q 1 1, yielding an interface Γ 1 p10, 1, 0.5q. Without any critical sections, component C 1 therefore requires a processor bandwidth of 0.1, see Figure 4(a).…”

“…Since X s is computed from a fixed fraction of the tasks' WCETs, this increases the X s P s ratio. The improved OWP (IOWP) in [14] performs equally well as ONP at the local level and its global admission test is superior compared to ONP. OWP is therefore preferred to ONP.…”