Context-Sensitive Measurement-Based Worst-Case Execution Time Estimation

Zolda, Michael; Bünte, Sven; Kirner, Raimund

doi:10.1109/rtcsa.2011.73

Cited by 5 publications

(2 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[30], [31], to combine static information on the program and measurements thus enabling the user to trade off between precision and cost. While hybrid techniques allow balancing between precision and costs, they do not warrant trustworthiness.…”

Section: B3 Computing a Value For P Padmentioning

confidence: 99%

EPC: Extended Path Coverage for Measurement-Based Probabilistic Timing Analysis

Ziccardi

Mezzetti

Vardanega

et al. 2015

2015 IEEE Real-Time Systems Symposium

View full text Add to dashboard Cite

Abstract-Measurement-based probabilistic timing analysis (MBPTA) computes trustworthy upper bounds to the execution time of software programs. MBPTA has the connotation, typical of measurement-based techniques, that the bounds computed with it only relate to what is observed in actual program traversals, which may not include the effective worst-case phenomena. To overcome this limitation, we propose Extended Path Coverage (EPC), a novel technique that allows extending the representativeness of the bounds computed by MBPTA. We make the observation data probabilistically path-independent by modifying the probability distribution of the observed timing behaviour so as to negatively compensate for any benefits that a basic block may draw from a path leading to it. This enables the derivation of trustworthy upper bounds to the probabilistic execution time of all paths in the program, even when the user-provided input vectors do not exercise the worst-case path. Our results confirm that using MBPTA with EPC produces fully trustworthy upper bounds with competitively small overestimation in comparison to state-of-the-art MBPTA techniques.

show abstract

Section: B3 Computing a Value For P Padmentioning

confidence: 99%

EPC: Extended Path Coverage for Measurement-Based Probabilistic Timing Analysis

Ziccardi

Mezzetti

Vardanega

et al. 2015

2015 IEEE Real-Time Systems Symposium

View full text Add to dashboard Cite

show abstract

“…We have implemented our approach for calculating WCET estimates as a component of the FORTAS framework (Zolda 2012). The FORTAS framework is a prototypical implementation of a portable, high-precision MBTA toolchain.…”

Section: The Fortas High-precision Mbta Frameworkmentioning

confidence: 99%

Calculating WCET estimates from timed traces

Zolda

Kirner

2015

Real-Time Syst

Self Cite

View full text Add to dashboard Cite

Real-time systems engineers face a daunting duty: they must ensure that each task in their system can always meet its deadline. To analyse schedulability they must know the worst-case execution time (WCET) of each task. However, determining exact WCETs is practically infeasible in cost-constrained industrial settings involving real-life code and COTS hardware. Static analysis tools that could yield sufficiently tight WCET bounds are often unavailable. As a result, interest in portable analysis approaches like measurement-based timing analysis is growing. We present an approach based on integer linear programming (ILP) for calculating a WCET estimate from a given database of timed execution traces. Unlike previous work, our method specifically aims at reducing overestimation, by means of an automatic classification of code executions into scenarios with differing worst-case behaviour. To ease the integration into existing analysis tool chains, our method is based on the implicit path enumeration technique. It can thus reuse flow facts from other analysis tools and produces ILP problems that can be solved by off-the-shelf solvers.

show abstract