Search Results

Documents authored by Vardanega, Tullio


Document
Mitigating Software-Instrumentation Cache Effects in Measurement-Based Timing Analysis

Authors: Enrique Díaz, Jaume Abella, Enrico Mezzetti, Irune Agirre, Mikel Azkarate-Askasua, Tullio Vardanega, and Francisco J. Cazorla

Published in: OASIcs, Volume 55, 16th International Workshop on Worst-Case Execution Time Analysis (WCET 2016)


Abstract
Measurement-based timing analysis (MBTA) is often used to determine the timing behaviour of software programs embedded in safety-aware real-time systems deployed in various industrial domains including automotive and railway. MBTA methods rely on some form of instrumentation, either at hardware or software level, of the target program or fragments thereof to collect execution-time measurement data. A known drawback of software-level instrumentation is that instrumentation itself does affect the timing and functional behaviour of a program, resulting in the so-called probe effect: leaving the instrumentation code in the final executable can negatively affect average performance and could not be even admissible under stringent industrial qualification and certification standards; removing it before operation jeopardizes the results of timing analysis as the WCET estimates on the instrumented version of the program cannot be valid any more due, for example, to the timing effects incurred by different cache alignments. In this paper, we present a novel approach to mitigate the impact of instrumentation code on cache behaviour by reducing the instrumentation overhead while at the same time preserving and consolidating the results of timing analysis.

Cite as

Enrique Díaz, Jaume Abella, Enrico Mezzetti, Irune Agirre, Mikel Azkarate-Askasua, Tullio Vardanega, and Francisco J. Cazorla. Mitigating Software-Instrumentation Cache Effects in Measurement-Based Timing Analysis. In 16th International Workshop on Worst-Case Execution Time Analysis (WCET 2016). Open Access Series in Informatics (OASIcs), Volume 55, pp. 1:1-1:11, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2016)


Copy BibTex To Clipboard

@InProceedings{diaz_et_al:OASIcs.WCET.2016.1,
  author =	{D{\'\i}az, Enrique and Abella, Jaume and Mezzetti, Enrico and Agirre, Irune and Azkarate-Askasua, Mikel and Vardanega, Tullio and Cazorla, Francisco J.},
  title =	{{Mitigating Software-Instrumentation Cache Effects in Measurement-Based Timing Analysis}},
  booktitle =	{16th International Workshop on Worst-Case Execution Time Analysis (WCET 2016)},
  pages =	{1:1--1:11},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-025-5},
  ISSN =	{2190-6807},
  year =	{2016},
  volume =	{55},
  editor =	{Schoeberl, Martin},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2016.1},
  URN =		{urn:nbn:de:0030-drops-68946},
  doi =		{10.4230/OASIcs.WCET.2016.1},
  annote =	{Keywords: WCET, Measurements, Instrumentation overhead}
}
Document
Measurement-Based Timing Analysis of the AURIX Caches

Authors: Leonidas Kosmidis, Davide Compagnin, David Morales, Enrico Mezzetti, Eduardo Quinones, Jaume Abella, Tullio Vardanega, and Francisco J. Cazorla

Published in: OASIcs, Volume 55, 16th International Workshop on Worst-Case Execution Time Analysis (WCET 2016)


Abstract
Cache memories are one of the hardware resources with higher potential to reduce worst-case execution time (WCET) costs for software programs with tight real-time constraints. Yet, the complexity of cache analysis has caused a large fraction of real-time systems industry to avoid using them, especially in the automotive sector. For measurement-based timing analysis (MBTA) - the dominant technique in domains such as automotive - cache challenges the definition of test scenarios stressful enough to produce (cache) layouts that causing high contention. In this paper, we present our experience in enabling the use of caches for a real automotive application running on an AURIX multiprocessor, using software randomization and measurement-based probabilistic timing analysis (MBPTA). Our results show that software randomization successfully exposes - in the experiments performed for timing analysis - cache related variability, in a manner that can be effectively captured by MBPTA.

Cite as

Leonidas Kosmidis, Davide Compagnin, David Morales, Enrico Mezzetti, Eduardo Quinones, Jaume Abella, Tullio Vardanega, and Francisco J. Cazorla. Measurement-Based Timing Analysis of the AURIX Caches. In 16th International Workshop on Worst-Case Execution Time Analysis (WCET 2016). Open Access Series in Informatics (OASIcs), Volume 55, pp. 9:1-9:11, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2016)


Copy BibTex To Clipboard

@InProceedings{kosmidis_et_al:OASIcs.WCET.2016.9,
  author =	{Kosmidis, Leonidas and Compagnin, Davide and Morales, David and Mezzetti, Enrico and Quinones, Eduardo and Abella, Jaume and Vardanega, Tullio and Cazorla, Francisco J.},
  title =	{{Measurement-Based Timing Analysis of the AURIX Caches}},
  booktitle =	{16th International Workshop on Worst-Case Execution Time Analysis (WCET 2016)},
  pages =	{9:1--9:11},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-025-5},
  ISSN =	{2190-6807},
  year =	{2016},
  volume =	{55},
  editor =	{Schoeberl, Martin},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2016.9},
  URN =		{urn:nbn:de:0030-drops-69028},
  doi =		{10.4230/OASIcs.WCET.2016.9},
  annote =	{Keywords: WCET, caches, AURIX, Automotive}
}
Document
Software-enforced Interconnect Arbitration for COTS Multicores

Authors: Marco Ziccardi, Alessandro Cornaglia, Enrico Mezzetti, and Tullio Vardanega

Published in: OASIcs, Volume 47, 15th International Workshop on Worst-Case Execution Time Analysis (WCET 2015)


Abstract
The advent of multicore processors complicates timing analysis owing to the need to account for the interference between cores accessing shared resources, which is not always easy to characterize in a safe and tight way. Solutions have been proposed that take two distinct but complementary directions: on the one hand, complex analysis techniques have been developed to provide safe and tight bounds to contention; on the other hand, sophisticated arbitration policies (hardware or software) have been proposed to limit or control inter-core interference. In this paper we propose a software-based TDMA-like arbitration of accesses to a shared interconnect (e.g. a bus) that prevents inter-core interference. A more flexible arbitration scheme is also proposed to reserve more bandwidth to selected cores while still avoiding contention. A proof-of-concept implementation on an AURIX TC277TU processor shows that our approach can apply to COTS processors, thus not relying on dedicated hardware arbiters, while introducing little overhead.

Cite as

Marco Ziccardi, Alessandro Cornaglia, Enrico Mezzetti, and Tullio Vardanega. Software-enforced Interconnect Arbitration for COTS Multicores. In 15th International Workshop on Worst-Case Execution Time Analysis (WCET 2015). Open Access Series in Informatics (OASIcs), Volume 47, pp. 11-20, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2015)


Copy BibTex To Clipboard

@InProceedings{ziccardi_et_al:OASIcs.WCET.2015.11,
  author =	{Ziccardi, Marco and Cornaglia, Alessandro and Mezzetti, Enrico and Vardanega, Tullio},
  title =	{{Software-enforced Interconnect Arbitration for COTS Multicores}},
  booktitle =	{15th International Workshop on Worst-Case Execution Time Analysis (WCET 2015)},
  pages =	{11--20},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-95-8},
  ISSN =	{2190-6807},
  year =	{2015},
  volume =	{47},
  editor =	{Cazorla, Francisco J.},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2015.11},
  URN =		{urn:nbn:de:0030-drops-52526},
  doi =		{10.4230/OASIcs.WCET.2015.11},
  annote =	{Keywords: Multicore, Resource Arbitration, Interference, Mixed-Criticality}
}
Document
Randomized Caches Can Be Pretty Useful to Hard Real-Time Systems

Authors: Enrico Mezzetti, Marco Ziccardi, Tullio Vardanega, Jaume Abella, Eduardo Quiñones, and Francisco J. Cazorla

Published in: LITES, Volume 2, Issue 1 (2015). Leibniz Transactions on Embedded Systems, Volume 2, Issue 1


Abstract
Cache randomization per se, and its viability for probabilistic timing analysis (PTA) of critical real-time systems, are receiving increasingly close attention from the scientific community and the industrial practitioners. In fact, the very notion of introducing randomness and probabilities in time-critical systems has caused strenuous debates owing to the apparent clash that this idea has with the strictly deterministic view traditionally held for those systems. A paper recently appeared in LITES (Reineke, J. (2014). Randomized Caches Considered Harmful in Hard Real-Time Systems. LITES, 1(1), 03:1-03:13.) provides a critical analysis of the weaknesses and risks entailed in using randomized caches in hard real-time systems. In order to provide the interested reader with a fuller, balanced appreciation of the subject matter, a critical analysis of the benefits brought about by that innovation should be provided also. This short paper addresses that need by revisiting the array of issues addressed in the cited work, in the light of the latest advances to the relevant state of the art. Accordingly, we show that the potential benefits of randomized caches do offset their limitations, causing them to be - when used in conjunction with PTA - a serious competitor to conventional designs.

Cite as

Enrico Mezzetti, Marco Ziccardi, Tullio Vardanega, Jaume Abella, Eduardo Quiñones, and Francisco J. Cazorla. Randomized Caches Can Be Pretty Useful to Hard Real-Time Systems. In LITES, Volume 2, Issue 1 (2015). Leibniz Transactions on Embedded Systems, Volume 2, Issue 1, pp. 01:1-01:10, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2015)


Copy BibTex To Clipboard

@Article{mezzetti_et_al:LITES-v002-i001-a001,
  author =	{Mezzetti, Enrico and Ziccardi, Marco and Vardanega, Tullio and Abella, Jaume and Qui\~{n}ones, Eduardo and Cazorla, Francisco J.},
  title =	{{Randomized Caches Can Be Pretty Useful to Hard Real-Time Systems}},
  journal =	{Leibniz Transactions on Embedded Systems},
  pages =	{01:1--01:10},
  ISSN =	{2199-2002},
  year =	{2015},
  volume =	{2},
  number =	{1},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LITES-v002-i001-a001},
  doi =		{10.4230/LITES-v002-i001-a001},
  annote =	{Keywords: Real-time systems, Probabilistic WCET, Randomized caches}
}
Document
Contention in Multicore Hardware Shared Resources: Understanding of the State of the Art

Authors: Gabriel Fernandez, Jaume Abella, Eduardo Quiñones, Christine Rochange, Tullio Vardanega, and Francisco J. Cazorla

Published in: OASIcs, Volume 39, 14th International Workshop on Worst-Case Execution Time Analysis (2014)


Abstract
The real-time systems community has over the years devoted considerable attention to the impact on execution timing that arises from contention on access to hardware shared resources. The relevance of this problem has been accentuated with the arrival of multicore processors. From the state of the art on the subject, there appears to be considerable diversity in the understanding of the problem and in the "approach" to solve it. This sparseness makes it difficult for any reader to form a coherent picture of the problem and solution space. This paper draws a tentative taxonomy in which each known approach to the problem can be categorised based on its specific goals and assumptions.

Cite as

Gabriel Fernandez, Jaume Abella, Eduardo Quiñones, Christine Rochange, Tullio Vardanega, and Francisco J. Cazorla. Contention in Multicore Hardware Shared Resources: Understanding of the State of the Art. In 14th International Workshop on Worst-Case Execution Time Analysis. Open Access Series in Informatics (OASIcs), Volume 39, pp. 31-42, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2014)


Copy BibTex To Clipboard

@InProceedings{fernandez_et_al:OASIcs.WCET.2014.31,
  author =	{Fernandez, Gabriel and Abella, Jaume and Qui\~{n}ones, Eduardo and Rochange, Christine and Vardanega, Tullio and Cazorla, Francisco J.},
  title =	{{Contention in Multicore Hardware Shared Resources: Understanding of the State of the Art}},
  booktitle =	{14th International Workshop on Worst-Case Execution Time Analysis},
  pages =	{31--42},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-69-9},
  ISSN =	{2190-6807},
  year =	{2014},
  volume =	{39},
  editor =	{Falk, Heiko},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2014.31},
  URN =		{urn:nbn:de:0030-drops-46027},
  doi =		{10.4230/OASIcs.WCET.2014.31},
  annote =	{Keywords: Contention, Multicores, WCET Analysis}
}
Document
Upper-bounding Program Execution Time with Extreme Value Theory

Authors: Francisco J. Cazorla, Tullio Vardanega, Eduardo Quiñones, and Jaume Abella

Published in: OASIcs, Volume 30, 13th International Workshop on Worst-Case Execution Time Analysis (2013)


Abstract
In this paper we discuss the limitations of and the precautions to account for when using Extreme Value Theory (EVT) to compute upper bounds to the execution time of programs. We analyse the requirements placed by EVT on the observations to be made of the events of interest, and the conditions that render safe the computations of execution time upper bounds. We also study the requirements that a recent EVT-based timing analysis technique, Measurement-Based Probabilistic Timing Analysis (MBPTA), introduces, besides those imposed by EVT, on the computing system under analysis to increase the trustworthiness of the upper bounds that it computes.

Cite as

Francisco J. Cazorla, Tullio Vardanega, Eduardo Quiñones, and Jaume Abella. Upper-bounding Program Execution Time with Extreme Value Theory. In 13th International Workshop on Worst-Case Execution Time Analysis. Open Access Series in Informatics (OASIcs), Volume 30, pp. 64-76, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2013)


Copy BibTex To Clipboard

@InProceedings{cazorla_et_al:OASIcs.WCET.2013.64,
  author =	{Cazorla, Francisco J. and Vardanega, Tullio and Qui\~{n}ones, Eduardo and Abella, Jaume},
  title =	{{Upper-bounding Program Execution Time with Extreme Value Theory}},
  booktitle =	{13th International Workshop on Worst-Case Execution Time Analysis},
  pages =	{64--76},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-54-5},
  ISSN =	{2190-6807},
  year =	{2013},
  volume =	{30},
  editor =	{Maiza, Claire},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2013.64},
  URN =		{urn:nbn:de:0030-drops-41232},
  doi =		{10.4230/OASIcs.WCET.2013.64},
  annote =	{Keywords: WCET, Extreme Value Theory, Probabilistic, Deterministic}
}
Document
Applying Measurement-Based Probabilistic Timing Analysis to Buffer Resources

Authors: Leonidas Kosmidis, Tullio Vardanega, Jaume Abella, Eduardo Quiñones, and Francisco J. Cazorla

Published in: OASIcs, Volume 30, 13th International Workshop on Worst-Case Execution Time Analysis (2013)


Abstract
The use of complex hardware makes it difficult for current timing analysis techniques to compute trustworthy and tight worst-case execution time (WCET) bounds. Those techniques require detailed knowledge of the internal operation and state of the platform, at both the software and hardware level. Obtaining that information for modern hardware platforms is increasingly difficult. Measurement-Based Probabilistic Timing Analysis (MBPTA) reduces the cost of acquiring the knowledge needed for computing trustworthy and tight WCET bounds. MBPTA based on Extreme Value Theory requires the execution time of processor instructions to be independent and identically distributed (i.i.d.), which can be achieved with some hardware support. Previous proposals show how those properties can be achieved for caches. This paper considers, for the first time, the implications on MBPTA of using buffer resources. Buffers in general, and first-come first-served (FCFS) buffers in particular, are of paramount importance as the complexity of hardware increases, since they allow managing contention in those resources where multiple requests may be pending. We show how buffers can be used in the context of MBPTA and provide illustrative examples.

Cite as

Leonidas Kosmidis, Tullio Vardanega, Jaume Abella, Eduardo Quiñones, and Francisco J. Cazorla. Applying Measurement-Based Probabilistic Timing Analysis to Buffer Resources. In 13th International Workshop on Worst-Case Execution Time Analysis. Open Access Series in Informatics (OASIcs), Volume 30, pp. 97-108, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2013)


Copy BibTex To Clipboard

@InProceedings{kosmidis_et_al:OASIcs.WCET.2013.97,
  author =	{Kosmidis, Leonidas and Vardanega, Tullio and Abella, Jaume and Qui\~{n}ones, Eduardo and Cazorla, Francisco J.},
  title =	{{Applying Measurement-Based Probabilistic Timing Analysis to Buffer Resources}},
  booktitle =	{13th International Workshop on Worst-Case Execution Time Analysis},
  pages =	{97--108},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-54-5},
  ISSN =	{2190-6807},
  year =	{2013},
  volume =	{30},
  editor =	{Maiza, Claire},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2013.97},
  URN =		{urn:nbn:de:0030-drops-41269},
  doi =		{10.4230/OASIcs.WCET.2013.97},
  annote =	{Keywords: WCET, Buffer, Probabilistic Timing Analysis}
}
Document
Complete Volume
OASIcs, Volume 23, WCET'12, Complete Volume

Authors: Tullio Vardanega

Published in: OASIcs, Volume 23, 12th International Workshop on Worst-Case Execution Time Analysis (2012)


Abstract
OASIcs, Volume 23, WCET'12, Complete Volume

Cite as

12th International Workshop on Worst-Case Execution Time Analysis. Open Access Series in Informatics (OASIcs), Volume 23, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2012)


Copy BibTex To Clipboard

@Proceedings{vardanega:OASIcs.WCET.2012,
  title =	{{OASIcs, Volume 23, WCET'12, Complete Volume}},
  booktitle =	{12th International Workshop on Worst-Case Execution Time Analysis},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-41-5},
  ISSN =	{2190-6807},
  year =	{2012},
  volume =	{23},
  editor =	{Vardanega, Tullio},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2012},
  URN =		{urn:nbn:de:0030-drops-35928},
  doi =		{10.4230/OASIcs.WCET.2012},
  annote =	{Keywords: \lbrackSpecial-Purpose and Application-Based Systems\rbrack: Real-time and embedded systems, \lbrackPerformance of systems\rbrack: Modelling techniques, Performance attribute Software/Program Verification, Testing and Debugging, \lbrackSoftware Engineering\rbrack: Software Architectures – Domain-specific architectures, Patterns}
}
Document
Front Matter
Frontmatter, Table of Contents, Preface, Workshop Organization, List of Authors

Authors: Tullio Vardanega

Published in: OASIcs, Volume 23, 12th International Workshop on Worst-Case Execution Time Analysis (2012)


Abstract
Frontmatter, Table of Contents, Preface, Workshop Organization, List of Authors

Cite as

12th International Workshop on Worst-Case Execution Time Analysis. Open Access Series in Informatics (OASIcs), Volume 23, pp. i-xi, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2012)


Copy BibTex To Clipboard

@InProceedings{vardanega:OASIcs.WCET.2012.i,
  author =	{Vardanega, Tullio},
  title =	{{Frontmatter, Table of Contents, Preface, Workshop Organization, List of Authors}},
  booktitle =	{12th International Workshop on Worst-Case Execution Time Analysis},
  pages =	{i--xi},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-41-5},
  ISSN =	{2190-6807},
  year =	{2012},
  volume =	{23},
  editor =	{Vardanega, Tullio},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2012.i},
  URN =		{urn:nbn:de:0030-drops-35625},
  doi =		{10.4230/OASIcs.WCET.2012.i},
  annote =	{Keywords: Frontmatter, Table of Contents, Preface, Workshop Organization, List of Authors}
}
Document
A Time-composable Operating System

Authors: Andrea Baldovin, Enrico Mezzetti, and Tullio Vardanega

Published in: OASIcs, Volume 23, 12th International Workshop on Worst-Case Execution Time Analysis (2012)


Abstract
Time composability is a guiding principle to the development and certification process of real-time embedded systems. Considerable efforts have been devoted to studying the role of hardware architectures - and their modern accelerating features - in enabling the hierarchical composition of the timing behaviour of software programs considered in isolation. Much less attention has been devoted to the effect of real-time Operating Systems (OS) on time composability at the application level. In fact, the very presence of the OS contributes to the variability of the execution time of the application directly and indirectly; by way of its own response time jitter and by its effect on the state retained by the processor hardware. We consider zero disturbance and steady behaviour as those characteristic properties that an operating system should exhibit, so as to be time-composable with the user applications. We assess those properties on the redesign of an ARINC compliant partitioned operating system, for use in avionics applications, and present some experimental results from a preliminary implementation of our approach within the scope of the EU FP7 PROARTIS project.

Cite as

Andrea Baldovin, Enrico Mezzetti, and Tullio Vardanega. A Time-composable Operating System. In 12th International Workshop on Worst-Case Execution Time Analysis. Open Access Series in Informatics (OASIcs), Volume 23, pp. 69-80, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2012)


Copy BibTex To Clipboard

@InProceedings{baldovin_et_al:OASIcs.WCET.2012.69,
  author =	{Baldovin, Andrea and Mezzetti, Enrico and Vardanega, Tullio},
  title =	{{A Time-composable Operating System}},
  booktitle =	{12th International Workshop on Worst-Case Execution Time Analysis},
  pages =	{69--80},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-41-5},
  ISSN =	{2190-6807},
  year =	{2012},
  volume =	{23},
  editor =	{Vardanega, Tullio},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2012.69},
  URN =		{urn:nbn:de:0030-drops-35589},
  doi =		{10.4230/OASIcs.WCET.2012.69},
  annote =	{Keywords: Real-time Operating System, Timing composability, ARINC}
}
Document
Bounding the Effects of Resource Access Protocols on Cache Behavior

Authors: Enrico Mezzetti, Marco Panunzio, and Tullio Vardanega

Published in: OASIcs, Volume 15, 10th International Workshop on Worst-Case Execution Time Analysis (WCET 2010)


Abstract
The assumption of task independence has long been consubstantial with the formulation of many schedulability analysis techniques. That assumption is evidently advantageous for the mathematical formulation of the analysis equations, but ill fit to capture the actual behavior of the system. Resource sharing is one of the system design dimensions that break the assumption of task independence. By shaking the very foundations of the real-time analysis theory, the advent of multicore systems has caused resurgence of interest in resource sharing and synchronization protocols, and also dawned the fact that the assumption of task independence may be forever broken. Research in cache-aware schedulability analysis instead has paid very little attention to the impact that synchronization protocols may have on cache behavior. A blocked task may in fact incur time penalties similar in kind to those caused by preemption, in that some useful code or data already loaded in the cache may be evicted while the task is blocked. In this paper we characterize the sources of cache-related blocking delay (CRBD). We then provide a bound on the CRBD for three synchronization protocols of interest. The comparison between these bounds provides striking evidence that an informed choice of the synchronization protocol helps contain the perturbing effects of blocking on the cache state.

Cite as

Enrico Mezzetti, Marco Panunzio, and Tullio Vardanega. Bounding the Effects of Resource Access Protocols on Cache Behavior. In 10th International Workshop on Worst-Case Execution Time Analysis (WCET 2010). Open Access Series in Informatics (OASIcs), Volume 15, pp. 11-22, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2010)


Copy BibTex To Clipboard

@InProceedings{mezzetti_et_al:OASIcs.WCET.2010.11,
  author =	{Mezzetti, Enrico and Panunzio, Marco and Vardanega, Tullio},
  title =	{{Bounding the Effects of Resource Access Protocols on Cache Behavior}},
  booktitle =	{10th International Workshop on Worst-Case Execution Time Analysis (WCET 2010)},
  pages =	{11--22},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-939897-21-7},
  ISSN =	{2190-6807},
  year =	{2010},
  volume =	{15},
  editor =	{Lisper, Bj\"{o}rn},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.WCET.2010.11},
  URN =		{urn:nbn:de:0030-drops-28217},
  doi =		{10.4230/OASIcs.WCET.2010.11},
  annote =	{Keywords: Resource access protocols, cache, worst-case response time}
}
Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail