Now showing items 21-39 of 39

  • Maximum-Contention Control Unit (MCCU): Resource Access Count and Contention Time Enforcement 

    Cardona, Jordi; Hernandez, Carles; Abella, Jaume; Cazorla, Francisco J. (IEEE, 2019-04-16)
    Conference lecture
    Open Access
    In real-time systems, the techniques to derive bounds to the contention tasks can suffer in multicore build on resource quota monitoring and enforcement. Existing techniques track and bound the number of requests to hardware ...
  • MC2: Multicore and Cache Analysis via Deterministic and Probabilistic Jitter Bounding 

    Díaz, Enrique; Fernández, Mikel; Kosmidis, Leonidas; Mezzetti, Enrico; Hernandez, Carles; Abella, Jaume; Cazorla, Francisco J. (Springer International Publishing, 2017-05-30)
    Conference lecture
    Open Access
    In critical domains, reliable software execution is increasingly involving aspects related to the timing dimension. This is due to the advent of high-performance (complex) hardware, used to provide the rising levels of ...
  • Measurement-based cache representativeness on multipath programs 

    Milutinovic, Suzana; Abella, Jaume; Mezzetti, Enrico; Cazorla, Francisco J. (Association for Computing Machinery (ACM), 2018-06)
    Conference lecture
    Open Access
    Autonomous vehicles in embedded real-time systems increase critical-software size and complexity whose performance needs are covered with high-performance hardware features like caches, which however hampers obtaining WCET ...
  • Measurement-Based Worst-Case Execution Time Estimation Using the Coefficient of Variation 

    Abella, Jaume; Padilla, Maria; del Castillo, Joan; Cazorla, Francisco J. (Association for Computing Machinery (ACM), 2017-07)
    Article
    Open Access
    Extreme Value Theory (EVT) has been historically used in domains such as finance and hydrology to model worst-case events (e.g., major stock market incidences). EVT takes as input a sample of the distribution of the variable ...
  • Modelling bus contention during system early design stages 

    Trilla, David; Hernandez, Carles; Abella, Jaume; Cazorla, Francisco J. (IEEE, 2017-07-31)
    Conference lecture
    Open Access
    Reliably upperbounding contention in multicore shared resources is of prominent importance in the early design phases of critical real-time systems to properly allocate time budgets to applications. However, during early ...
  • Modelling multicore contention on the AURIXTM TC27x 

    Díaz, Enrique; Mezzetti, Enrico; Kosmidis, Leonidas; Abella, Jaume; Cazorla, Francisco J. (Association for Computing Machinery (ACM), 2018-06-24)
    Conference lecture
    Open Access
    Multicores are becoming ubiquitous in automotive. Yet, the expected benefits on integration are challenged by multicore contention concerns on timing V&V. Worst-case execution time (WCET) estimates are required as early ...
  • Multicore Early Design Stage Guaranteed Performance Estimates for the Space Domain 

    Fernandez, Mikel; Fernandez, Gabriel; Abella, Jaume; Cazorla, Francisco J. (IEEE, 2019-05-16)
    Conference lecture
    Open Access
    The ability to produce early guaranteed performance (worst-case execution time) estimates for multicores, i.e. before software from different providers gets integrated onto the same critical system, is pivotal. This helps ...
  • NoCo: ILP-Based Worst-Case Contention Estimation for Mesh Real-Time Manycores 

    Cardona, Jordi; Hernandez, Carles; Mezzetti, Enrico; Abella, Jaume; Cazorla, Francisco J. (IEEE, 2019-01-07)
    Conference lecture
    Open Access
    Manycores are capable of providing the computational demands required by functionally-advanced critical applications in domains such as automotive and avionics. In manycores a network-on-chip (NoC) provides access to shared ...
  • On assessing the viability of probabilistic scheduling with dependent tasks 

    Abella, Jaume; Mezzetti, Enrico; Cazorla, Francisco J. (Association for Computing Machinery (ACM), 2019-04-08)
    Conference lecture
    Open Access
    Despite the significant interest, in the last years, in probabilistic scheduling and probabilistic timing analysis, the interrelation between them has been scarcely addressed. Probabilistic scheduling approaches typically ...
  • On the tailoring of CAST-32A certification guidance to real COTS multicore architectures 

    Agirre, Irune; Abella, Jaume; Azkarate-Askasua, Mikel; Cazorla, Francisco J. (IEEE, 2018-03-12)
    Conference lecture
    Open Access
    The use of Commercial Off-The-Shelf (COTS) multicores in real-time industry is on the rise due to multicores' potential performance increase and energy reduction. Yet, the unpredictable impact on timing of contention in ...
  • On uses of extreme value theory fit for industrial-quality WCET analysis 

    Milutinovic, Suzana; Mezzetti, Enrico; Abella, Jaume; Vardanega, Tullio; Cazorla, Francisco J. (IEEE, 2017-07-31)
    Conference lecture
    Open Access
    Over the last few years, considerable interest has arisen in measurement-based probabilistic timing analysis. The term MBPTA has been used to indistinctly refer to a variety of different applications of Extreme Value Theory ...
  • Probabilistic Worst-Case Timing Analysis: Taxonomy and Comprehensive Survey 

    Cazorla, Francisco J.; Kosmidis, Leonidas; Mezzetti, Enrico; Hernandez, Carles; Abella, Jaume; Vardanega, Tullio (ACM, 2019-02-01)
    Article
    Open Access
    The unabated increase in the complexity of the hardware and software components of modern embedded real-time systems has given momentum to a host of research in the use of probabilistic and statistical techniques for timing ...
  • PROXIMA: Improving Measurement-Based Timing Analysis through Randomisation and Probabilistic Analysis 

    Cazorla, Francisco J.; Abella, Jaume; Andersson, Jan; Vardanega, Tullio; Vatrinet, Francis; Bate, Iain; Broster, Ian; Azkarate-askasua, Mikel; Wartel, Franck; Cucu, Liliana; Cros, Fabrice; Farrall, Glenn; Gogonel, Adriana; Gianarro, Andrea; Triquet, Benoit; Hernandez, Carles; Lo, Code; Maxim, Cristian; Morales, David; Quiñones, Eduardo; Mezzetti, Enrico; Kosmidis, Leonidas; Aguirre, Irune; Fernandez, Mikel; Slijepcevic, Mladen; Conmy, Philippa; Talaboulma, Walid (IEEE, 2016-08-31)
    Conference lecture
    Open Access
    The use of increasingly complex hardware and software platforms in response to the ever rising performance demands of modern real-time systems complicates the verification and validation of their timing behaviour, which ...
  • Reconciling Time Predictability and Performance in Future Computing Systems 

    Cazorla, Francisco J.; Abella, Jaume; Mezzetti, Enrico; Hernandez, Carles; Vardanega, Tullio; Bernat, Guillem (IEEE, 2018-04)
    Article
    Open Access
    MBTA studies the system’s timing in analysis scenarios, to determine upper bounds to the worst-case execution-time behavior that may occur at operation. MBTA’s challenge is to construct analysis-time scenarios that help ...
  • Safety-Related Challenges and Opportunities for GPUs in the Automotive Domain 

    Alcaide, Sergi; Kosmidis, Leonidas; Tabani, Hamid; Hernandez, Carles; Abella, Jaume; Cazorla, Francisco J. (IEEE, 2018-10-09)
    Article
    Open Access
    GPUs have been shown to cover the computing performance needs of autonomous driving (AD) systems. However, since the GPUs used for AD build on designs for the mainstream market, they may lack fundamental properties for ...
  • Software Time Reliability in the Presence of Cache Memories 

    Milutinovic, Suzana; Abella, Jaume; Agirre, Irune; Azkarate-Askasua, Mikel; Mezzetti, Enrico; Vardanega, Tullio; Cazorla, Francisco J. (Springer International Publishing, 2017-05-30)
    Conference lecture
    Open Access
    The use of caches challenges measurement-based timing analysis (MBTA) in critical embedded systems. In the presence of caches, the worst-case timing behavior of a system heavily depends on how code and data are laid out ...
  • Time-Randomized Wormhole NoCs for Critical Applications 

    Slijepcevic, Mladen; Hernandez, Carles; Abella, Jaume; Cazorla, Francisco J. (Association for Computing Machinery (ACM), 2019-02)
    Article
    Open Access
    Wormhole-based NoCs (wNoCs) are widely accepted in high-performance domains as the most appropriate solution to interconnect an increasing number of cores in the chip. However, wNoCs suitability in the context of critical ...
  • Timing verification of fault-tolerant chips for safety-critical applications in harsh environments 

    Slijepcevic, Mladen; Kosmidis, Leonidas; Abella Ferrer, Jaume; Quiñones, Eduardo; Cazorla, Francisco J. (2014-11-01)
    Article
    Restricted access - publisher's policy
    Critical real-time embedded systems feature complex safety-related, performance-demanding functionality. High-performance hardware and software can provide such functionality, but the use of aggressive technologies and ...
  • Work-in-Progress Paper: An Analysis of the Impact of Dependencies on Probabilistic Timing Analysis and Task Scheduling 

    Mezzetti, Enrico; Abella, Jaume; Hernandez, Carles; Cazorla, Francisco J. (IEEE, 2018-02-01)
    Conference lecture
    Open Access
    Recently there has been a renewed interest for probabilistic timing analysis (PTA) and probabilistic task scheduling (PTS). Despite the number of works in both fields, the link between them is weak: works on the latter ...