DOCSLIB.ORG

The Many Approaches to Real-Time and Safety Critical Linux Systems

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Many Approaches to Real-Time and Safety Critical Linux Systems Corporate Technology The Many Approaches to Real-Time and Safety-Critical Linux Open Source Summit Japan 2017 Prof. Dr. Wolfgang Mauerer Siemens AG, Corporate Research and Technologies Smart Embedded Systems Corporate Competence Centre Embedded Linux Copyright c 2017, Siemens AG. All rights reserved. Page 1 31. Mai 2017 W. Mauerer Siemens Corporate Technology Corporate Technology The Many Approaches to Real-Time and Safety-Critical Linux Open Source Summit Japan 2017 Prof. Dr. Wolfgang Mauerer, Ralf Ramsauer, Andreas Kolbl¨ Siemens AG, Corporate Research and Technologies Smart Embedded Systems Corporate Competence Centre Embedded Linux Copyright c 2017, Siemens AG. All rights reserved. Page 1 31. Mai 2017 W. Mauerer Siemens Corporate Technology Overview 1 Real-Time and Safety 2 Approaches to Real-Time Architectural Possibilities Practical Approaches 3 Approaches to Linux-Safety 4 Guidelines and Outlook Page 2 31. Mai 2017 W. Mauerer Siemens Corporate Technology Introduction & Overview About Siemens Corporate Technology: Corporate Competence Centre Embedded Linux Technical University of Applied Science Regensburg Theoretical Computer Science Head of Digitalisation Laboratory Target Audience Assumptions System Builders & Architects, Software Architects Linux Experience available Not necessarily RT-Linux and Safety-Critical Linux experts Page 3 31. Mai 2017 W. Mauerer Siemens Corporate Technology A journey through the worlds of real-time and safety Page 4 31. Mai 2017 W. Mauerer Siemens Corporate Technology Outline 1 Real-Time and Safety 2 Approaches to Real-Time Architectural Possibilities Practical Approaches 3 Approaches to Linux-Safety 4 Guidelines and Outlook Page 5 31. Mai 2017 W. Mauerer Siemens Corporate Technology Real-Time: What and Why? I Real Time Real Fast Deterministic responses to stimuli Caches, TLB, Lookahead Bounded latencies (not too late, not too Pipelines early) Optimise average case Repeatable results Optimise/quantify worst case Page 6 31. Mai 2017 W. Mauerer Siemens Corporate Technology Real-Time: What and Why? II Type Characteristics Use Cases Soft Real-Time Subjective Deadlines Media rendering, I/O 95% Real-Time Deadlines met most of the time, Data acquisition, finance, navi- misses can be compensated gation, . 100% Real-Time Miss deadline: Defects occur Industrial Automation & control, Robotics, Airplanes, . Ensuring Real-Time Statistical testing WCET calculation + schedulability testing Formal verification Page 7 31. Mai 2017 W. Mauerer Siemens Corporate Technology Real-Time: What and Why? II Type Characteristics Use Cases Soft Real-Time Subjective Deadlines Media rendering, I/O 95% Real-Time Deadlines met most of the time, Data acquisition, finance, navi- misses can be compensated gation, . 100% Real-Time Miss deadline: Defects occur Industrial Automation & control, Robotics, Airplanes, . Ensuring Real-Time Statistical testing WCET calculation + schedulability testing Formal verification Page 7 31. Mai 2017 W. Mauerer Siemens Corporate Technology Safety: What and Why? Some undesirables Safety-Critical Systems Brake: Segfault! Malfunctions of the system (may) result in Engines full speed ahead: Segfault! death/injury to people and so on. damage to equipment/property environmental harm Safety = Real-Time, but often coupled! 6 100% RT + fatal consequences Safety ) Page 8 31. Mai 2017 W. Mauerer Siemens Corporate Technology Safety: Standards Robotic Devices Routes to Safety Electrical Power Drive ISO10218 Industrial Process IEC61800 IEC61511 Standard compliant “umbrella” standard Railways Machinery development IEC62278 IEC61508 IEC62061 Proven in use Nuclear Power Plants Medical Device Software Compliant IEC61513 Automotive IEC62304 non-compliant ISO26262 development Challenge: Page 9 31. Mai 2017 W. Mauerer Siemens Corporate Technology Outline 1 Real-Time and Safety 2 Approaches to Real-Time Architectural Possibilities Practical Approaches 3 Approaches to Linux-Safety 4 Guidelines and Outlook Page 10 31. Mai 2017 W. Mauerer Siemens Corporate Technology Approaches to Real-Time Linux € Δt € App App +/- Engineering Δt € Control Application RT Latency € RT Latency Specialised Languages - Standard Languages Control Framework +RT-Bridge +RT-Net Specialised OS + Middleware Proprietary Hardware Dynamic -Overhead Static Linux +RT COTS Hardware +FPGA Why Real-Time Linux? Commodity features Subtractive vs. additive Engineering Multi-Core utilisation ... Page 11 31. Mai 2017 W. Mauerer Siemens Corporate Technology Architectural possibilities I 1 Traditional RTOS in side-device Pros and Cons 2 RT-Enhanced Kernel 3 Countless variants available 3 Separation Kernel 3 Pre-Certified Versions 4 Co-Kernel 3 Extreme simplicity 5 Asymmetric Multiprocessing 7 Hard to extend with state-of-the art IT 7 Vendor lock-in 7 Unusual APIs etc. Page 12 31. Mai 2017 W. Mauerer Siemens Corporate Technology Architectural possibilities I 1 Traditional RTOS in side-device Pros and Cons 2 RT-Enhanced Kernel 3 Leverage existing Linux Know-How 3 Separation Kernel 3 Integration of high-level technologies 4 Co-Kernel with little effort 5 Asymmetric Multiprocessing 7 Certification complicated 7 Complex system 7 Only statistical RT assurance Page 12 31. Mai 2017 W. Mauerer Siemens Corporate Technology Architectural possibilities I 1 Traditional RTOS in side-device Pros and Cons 2 RT-Enhanced Kernel 3 Clean split between RT and non-RT 3 Separation Kernel 3 Substantial certification experience 4 Co-Kernel 7 Typically strong HW coupling 5 Asymmetric Multiprocessing 7 Vendor Lock-In Page 12 31. Mai 2017 W. Mauerer Siemens Corporate Technology Architectural possibilities I 1 Traditional RTOS in side-device Pros and Cons 2 RT-Enhanced Kernel 3 Clean split between RT and non-RT 3 Separation Kernel 3 Ressource efficient 4 Co-Kernel 7 Non-standard maintenance efforts 5 Asymmetric Multiprocessing 7 Implicit couplings Page 12 31. Mai 2017 W. Mauerer Siemens Corporate Technology Architectural possibilities I 1 Traditional RTOS in side-device Pros and Cons 2 RT-Enhanced Kernel 3 Combine advantages of split systems 3 Separation Kernel with single HW basis 4 Co-Kernel 3 Near bare metal performance 5 Asymmetric Multiprocessing 7 Implicit couplings 7 Relatively new development 7 Maintenance overhead Page 12 31. Mai 2017 W. Mauerer Siemens Corporate Technology Architectural possibilities II Commonality System partitioning! Logical instead of physical Workloads of different criticality handled by different system portions Mixed ) Criticality Page 13 31. Mai 2017 W. Mauerer Siemens Corporate Technology Practical Approaches Practical Approaches Preempt-RT Xenomai/ipipe ARM/PRU GPUs/FPGA assisted RT Traditional RTOSes Page 14 31. Mai 2017 W. Mauerer Siemens Corporate Technology Preempt-RT I Enhance Linux with RT capabilities RT Howto Preemption (incl. preemption at kernel Don’t anything stupid level) Lock memory (no paging) No inappropriate syscalls (networking Deterministic (and fine-grained) timing etc.) behaviour No block device access Avoidance of priority inversion (prio ... inheritance/ceiling) Linux Foundation: Official project (goal: upstreaming code) Typical Jitter: 50µs (x86), 150 µs (rpi) Page 15 31. Mai 2017 W. Mauerer Siemens Corporate Technology Preempt-RT II Page 16 31. Mai 2017 W. Mauerer Siemens Corporate Technology 400 Types of patches 300 200 Number of commits 100 0 backport 3.0.101-rt130 3.2.78-rt113 3.4.111-rt141 forwardport 3.6.11-rt31 3.8.13-rt16 3.10.101-rt111 invariant Stack Version 3.12.57-rt77 3.14.65-rt68 3.18.29-rt30 4.0.8-rt6 4.1.20-rt23 4.4.9-rt17 4.6-rc7-rt1 Preempt-RT III: Pros and Cons Advantages Disadvantages 3 Patch availability and community 7 Functional certifiability limited support 7 Achieving smallest latencies requires 3 Re-use of engineering knowledge substantial system knowledge 3 Excellent multi-core scalability 7 Mixing RT and non-RT easy 3 RT in userspace easily possible 7 Fixing problems requires substantial system knowledge Page 17 31. Mai 2017 W. Mauerer Siemens Corporate Technology Xenomai 3.0 I Userspace Task Task Task Task Task Xenomai: RTOS-to-Linux Process Provides skins for traditional RTOSes Scheduler A Preemption Scheduler B Two modes of operation Kernel Run on top of Linux (w. or w/o RT Dispatching and Collaboration Services capabilities) IRQ IRQ IRQ IRQ Run over co-kernel extension Hardware (patched Linux required) ipipe patch: 450-600 KiB (depending on arch), (mostly) stable over time Typical Jitter: 10µs (x86), 50 µs (rpi) Image source: Siemens AG, CC BY-SA 3.0 Page 18 31. Mai 2017 W. Mauerer Siemens Corporate Technology Xenomai 3.0 II: Architecture sketch Image source: Xenomai.org, CC BY-SA 3.0 Page 19 31. Mai 2017 W. Mauerer Siemens Corporate Technology Xenomai 3.0 II: Architecture sketch Image source: Xenomai.org, CC BY-SA 3.0 Page 19 31. Mai 2017 W. Mauerer Siemens Corporate Technology Xenomai 3.0 III: Pros and Cons Cobalt (Co-Kernel) Mercury (Preempt-RT) 3 Clean split between RT/non-RT 3 Architectural basis maintained by (transition is signalled) substantial community 3 Light-weight in low-end platforms (lock 3 Very solid skin framework w/o invasive contention, cache usage etc.) core changes 7 Very limited number of 7 Legacy scheduling not always 100% developers/small community reproducible 7 Porting effort required; availability lag 7 Inadvertently mixing RT and non-RT 7 Regressions on upstream changes easier Page 20 31. Mai 2017 W. Mauerer Siemens Corporate Technology ARM + PRU I ARM Subsystem Programmable Real-Time Unit (PRU) Subsystem PRU0 PRU0 PRU1 I/O (200MHz) (200MHz) Cortex-A PRU1 ShareD Inst. Data
Load more

Recommended publications
  • Industrial Control Via Application Containers: Migrating from Bare-Metal to IAAS
    Industrial Control via Application Containers: Migrating from Bare-Metal to IAAS Florian Hofer, Student Member, IEEE Martin A. Sehr Antonio Iannopollo, Member, IEEE Faculty of Computer Science Corporate Technology EECS Department Free University of Bolzano-Bozen Siemens Corporation University of California Bolzano, Italy Berkeley, CA 94704, USA Berkeley, CA 94720, USA fl[email protected] [email protected] [email protected] Ines Ugalde Alberto Sangiovanni-Vincentelli, Fellow, IEEE Barbara Russo Corporate Technology EECS Department Faculty of Computer Science Siemens Corporation University of California Free University of Bolzano-Bozen Berkeley, CA 94704, USA Berkeley, CA 94720, USA Bolzano, Italy [email protected] [email protected] [email protected] Abstract—We explore the challenges and opportunities of control design full authority over the environment in which shifting industrial control software from dedicated hardware to its software will run, it is not straightforward to determine bare-metal servers or cloud computing platforms using off the under what conditions the software can be executed on cloud shelf technologies. In particular, we demonstrate that executing time-critical applications on cloud platforms is viable based on computing platforms due to resource virtualization. Yet, we a series of dedicated latency tests targeting relevant real-time believe that the principles of Industry 4.0 present a unique configurations. opportunity to explore complementing traditional automation Index Terms—Industrial Control Systems, Real-Time, IAAS, components with a novel control architecture [3]. Containers, Determinism We believe that modern virtualization techniques such as application containerization [3]–[5] are essential for adequate I. INTRODUCTION utilization of cloud computing resources in industrial con- Emerging technologies such as the Internet of Things and trol systems.
    [Show full text]
  • Overrun Handling for Mixed-Criticality Support in RTEMS Kuan-Hsun Chen, Georg Von Der Brüggen, Jian-Jia Chen
    Overrun Handling for Mixed-Criticality Support in RTEMS Kuan-Hsun Chen, Georg von der Brüggen, Jian-Jia Chen To cite this version: Kuan-Hsun Chen, Georg von der Brüggen, Jian-Jia Chen. Overrun Handling for Mixed-Criticality Support in RTEMS. WMC 2016, Nov 2016, Porto, Portugal. hal-01438843 HAL Id: hal-01438843 https://hal.archives-ouvertes.fr/hal-01438843 Submitted on 25 Jan 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Overrun Handling for Mixed-Criticality Support in RTEMS Kuan-Hsun Chen, Georg von der Bruggen,¨ and Jian-Jia Chen Department of Informatics, TU Dortmund University, Germany Email: fkuan-hsun.chen, georg.von-der-brueggen, [email protected] Abstract—Real-time operating systems are not only used in of real-time operation systems is sufficient. However, some embedded real-time systems but also useful for the simulation and applications also have tasks with arbitrary deadlines, i.e., for validation of those systems. During the evaluation of our paper some tasks D > T . If the tasks are strictly periodic, this about Systems with Dynamic Real-Time Guarantees that appears i i in RTSS 2016 we discovered certain unexpected system behavior leads to a situation where two or more instances of the same in the open-source real-time operating system RTEMS.
    [Show full text]
  • OPERATING SYSTEMS.Ai
    Introduction Aeroflex Gaisler provides LEON and ERC32 users with a wide range of popular embedded operating systems. Ranging from very small footprint task handlers to full featured Real-Time Operating System (RTOS). A summary of available operating systems and their characteristics is outlined below. VxWorks The VxWorks SPARC port supports LEON3/4 and LEON2. Drivers for standard on-chip peripherals are included. The port supports both non-MMU and MMU systems allowing users to program fast and secure applications. Along with the graphical Eclipse based workbench comes the extensive VxWorks documentation. • MMU and non-MMU system support • SMP support (in 6.7 and later) • Networking support (Ethernet 10/100/1000) • UART, Timer, and interrupt controller support • PCI, SpaceWire, CAN, MIL-STD-1553B, I2C and USB host controller support • Eclipse based Workbench • Commercial license ThreadX The ThreadX SPARC port supports LEON3/4 and its standard on-chip peripherals. ThreadX is an easy to learn and understand advanced pico-kernel real-time operating system designed specifically for deeply embedded applications. ThreadX has a rich set of system services for memory allocation and threading. • Non-MMU system support • Bundled with newlib C library • Support for NetX, and USBX ® • Very small footprint • Commercial license Nucleus Nucleus is a real time operating system which offers a rich set of features in a scalable and configurable manner. • UART, Timer, Interrupt controller, Ethernet (10/100/1000) • TCP offloading and zero copy TCP/IP stack (using GRETH GBIT MAC) • USB 2.0 host controller and function controller driver • Small footprint • Commercial license LynxOS LynxOS is an advanced RTOS suitable for high reliability environments.
    [Show full text]
  • Final Report
    Parallel Programming Models for Space Systems BSC - Evidence ESA Contract No. 4000114391/15/NL/Cbi/GM Final Report Parallel Programming Models for Space Systems (ESA Contract No. 4000114391/15/NL/Cbi/GM) Main contractor Subcontractor Barcelona Supercomputing Center (BSC) Evidence Srl. Eduardo Quiñones, Paolo Gai, [email protected] [email protected] Dissemination level: All information contained in this document is puBlic June 2016 1 Parallel Programming Models for Space Systems BSC - Evidence ESA Contract No. 4000114391/15/NL/Cbi/GM Table of Contents 1 Introduction ..................................................................................................... 3 2 Future work: Next development activities to reach higher TRL (5/6) ................ 4 Annex I - D1.1. Report on parallelisation experiences for the space application .... 5 Annex II - D2.1. Report on the evaluation of current implementations of OpenMP ............................................................................................................................ 23 Annex III - D3.1. Report on the applicability of OpenMP4 on multi-core space platforms ............................................................................................................ 36 2 Parallel Programming Models for Space Systems BSC - Evidence ESA Contract No. 4000114391/15/NL/Cbi/GM 1 Introduction High-performance parallel architectures are becoming a reality in the critical real-time embedded systems in general, and in the space domain in particular. This is the case of the
    [Show full text]
  • Enabling Mobile Service Continuity Across Orchestrated Edge Networks
    This is a postprint version of the following published document: Abdullaziz, O. I., Wang, L. C., Chundrigar, S. B. y Huang, K. L. (2019). Enabling Mobile Service Continuity across Orchestrated Edge Networks. IEEE Transactions on Network Science and Engineering, 7(3), pp. 1774-1787. DOI: https://doi.org/10.1109/TNSE.2019.2953129 © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Enabling Mobile Service Continuity across Orchestrated Edge Networks Osamah Ibrahiem Abdullaziz, Student Member, IEEE, Li-Chun Wang, Fellow, IEEE, Shahzoob Bilal Chundrigar and Kuei-Li Huang Abstract—Edge networking has become an important technology for providing low-latency services to end users. However, deploying an edge network does not guarantee continuous service for mobile users. Mobility can cause frequent interruptions and network delays as users leave the initial serving edge. In this paper, we propose a solution to provide transparent service continuity for mobile users in large-scale WiFi networks. The contribution of this work has three parts. First, we propose ARNAB architecture to achieve mobile service continuity. The term ARNAB means rabbit in Arabic, which represents an Architecture for Transparent Service Continuity via Double-tier Migration. The first tier migrates user connectivity, while the second tier migrates user containerized applications. ARNAB provides mobile services just like rabbits hop through the WiFi infrastructure.
    [Show full text]
  • Building Embedded Linux Systems ,Roadmap.18084 Page Ii Wednesday, August 6, 2008 9:05 AM
    Building Embedded Linux Systems ,roadmap.18084 Page ii Wednesday, August 6, 2008 9:05 AM Other Linux resources from O’Reilly Related titles Designing Embedded Programming Embedded Hardware Systems Linux Device Drivers Running Linux Linux in a Nutshell Understanding the Linux Linux Network Adminis- Kernel trator’s Guide Linux Books linux.oreilly.com is a complete catalog of O’Reilly’s books on Resource Center Linux and Unix and related technologies, including sample chapters and code examples. ONLamp.com is the premier site for the open source web plat- form: Linux, Apache, MySQL, and either Perl, Python, or PHP. Conferences O’Reilly brings diverse innovators together to nurture the ideas that spark revolutionary industries. We specialize in document- ing the latest tools and systems, translating the innovator’s knowledge into useful skills for those in the trenches. Visit con- ferences.oreilly.com for our upcoming events. Safari Bookshelf (safari.oreilly.com) is the premier online refer- ence library for programmers and IT professionals. Conduct searches across more than 1,000 books. Subscribers can zero in on answers to time-critical questions in a matter of seconds. Read the books on your Bookshelf from cover to cover or sim- ply flip to the page you need. Try it today for free. main.title Page iii Monday, May 19, 2008 11:21 AM SECOND EDITION Building Embedded Linux SystemsTomcat ™ The Definitive Guide Karim Yaghmour, JonJason Masters, Brittain Gilad and Ben-Yossef, Ian F. Darwin and Philippe Gerum Beijing • Cambridge • Farnham • Köln • Sebastopol • Taipei • Tokyo Building Embedded Linux Systems, Second Edition by Karim Yaghmour, Jon Masters, Gilad Ben-Yossef, and Philippe Gerum Copyright © 2008 Karim Yaghmour and Jon Masters.
    [Show full text]
  • KINTSUGI Identifying & Addressing Challenges in Embedded Binary
    KINTSUGI Identifying & addressing challenges in embedded binary security jos wetzels Supervisors: Prof. dr. Sandro Etalle Ali Abbasi, MSc. Department of Mathematics and Computer Science Eindhoven University of Technology (TU/e) June 2017 Jos Wetzels: Kintsugi, Identifying & addressing challenges in embed- ded binary security, © June 2017 To my family Kintsugi ("golden joinery"), is the Japanese art of repairing broken pottery with lacquer dusted or mixed with powdered gold, silver, or platinum. As a philosophy, it treats breakage and repair as part of the history of an object, rather than something to disguise. —[254] ABSTRACT Embedded systems are found everywhere from consumer electron- ics to critical infrastructure. And with the growth of the Internet of Things (IoT), these systems are increasingly interconnected. As a re- sult, embedded security is an area of growing concern. Yet a stream of offensive security research, as well as real-world incidents, contin- ues to demonstrate how vulnerable embedded systems actually are. This thesis focuses on binary security, the exploitation and miti- gation of memory corruption vulnerabilities. We look at the state of embedded binary security by means of quantitative and qualitative analysis and identify several gap areas and show embedded binary security to lag behind the general purpose world significantly. We then describe the challenges and limitations faced by embedded exploit mitigations and identify a clear open problem area that war- rants attention: deeply embedded systems. Next, we outline the cri- teria for a deeply embedded exploit mitigation baseline. Finally, as a first step to addressing this problem area, we designed, implemented and evaluated µArmor : an exploit mitigation baseline for deeply em- bedded systems.
    [Show full text]
  • Flight Software Workshop 2007 ( FSW-07)
    Flight Software Workshop 2007 ( FSW-07) Current and Future Flight Operating Systems Alan Cudmore Flight Software Branch NASAIGSFC November 2007 Page I Outline Types of Real Time Operating Systems - Classic Real Time Operating Systems - Hybrid Real Time Operating Systems - Process Model Real Time Operating Systems - Partitioned Real Time Operating Systems Is the Classic RTOS Showing it's Age? Process Model RTOS for Flight Systems Challenges of Migrating to a Process Model RTOS Which RTOS Solution is Best? Conclusion November 2007 Page 2 GSFC Satellites with COTS Real (waiting for launch) (launched 8/92) (launched 12/98) (launched 3/98) (launched 2/99) (12/04) XTE (launched 12/95) TRMM (launched 11/97) JWST lSlM (201 1) Icesat GLAS f01/03) MAP (launched 06/01) LRO HST 386 4llH -%Y ST-5 (5/06) November 2007 Page 3 Classic Real Time OS What is a "Classic" RTOS? - Developed for easy COTS development on common 16 and 32 bit CPUs. - Designed for systems with single address space, and low resources - Literally Dozens of choices with a wide array of features. November 2007 Page 4 Classic RTOS - VRTX Ready Systems VRTX Size: Small - 8KB RTOS Kernel Provides: Very basic RTOS services Used on: - Small Explorer Missions Used from 1992 to 1999 8086 and 80386 Processors - Medium Explorer Missions XTE (1995) TRMM (1997) 80386 Processors - Hubble Space Telescope 80386 Processors Advantages: - Small, fast - Uses 80386 memory protection -- A feature we have missed since we stopped using it! Current use: - Only being maintained, not used for new development
    [Show full text]
  • Embedded Operating Systems
    7 Embedded Operating Systems Claudio Scordino1, Errico Guidieri1, Bruno Morelli1, Andrea Marongiu2,3, Giuseppe Tagliavini3 and Paolo Gai1 1Evidence SRL, Italy 2Swiss Federal Institute of Technology in Zurich (ETHZ), Switzerland 3University of Bologna, Italy In this chapter, we will provide a description of existing open-source operating systems (OSs) which have been analyzed with the objective of providing a porting for the reference architecture described in Chapter 2. Among the various possibilities, the ERIKA Enterprise RTOS (Real-Time Operating System) and Linux with preemption patches have been selected. A description of the porting effort on the reference architecture has also been provided. 7.1 Introduction In the past, OSs for high-performance computing (HPC) were based on custom-tailored solutions to fully exploit all performance opportunities of supercomputers. Nowadays, instead, HPC systems are being moved away from in-house OSs to more generic OS solutions like Linux. Such a trend can be observed in the TOP500 list [1] that includes the 500 most powerful supercomputers in the world, in which Linux dominates the competition. In fact, in around 20 years, Linux has been capable of conquering all the TOP500 list from scratch (for the first time in November 2017). Each manufacturer, however, still implements specific changes to the Linux OS to better exploit specific computer hardware features. This is especially true in the case of computing nodes in which lightweight kernels are used to speed up the computation. 173 174 Embedded Operating Systems Figure 7.1 Number of Linux-based supercomputers in the TOP500 list. Linux is a full-featured OS, originally designed to be used in server or desktop environments.
    [Show full text]
  • Timing Comparison of the Real-Time Operating Systems for Small Microcontrollers
    S S symmetry Article Timing Comparison of the Real-Time Operating Systems for Small Microcontrollers Ioan Ungurean 1,2 1 Faculty of Electrical Engineering and Computer Science; Stefan cel Mare University of Suceava, 720229 Suceava, Romania; [email protected] 2 MANSiD Integrated Center, Stefan cel Mare University, 720229 Suceava, Romania Received: 9 March 2020; Accepted: 1 April 2020; Published: 8 April 2020 Abstract: In automatic systems used in the control and monitoring of industrial processes, fieldbuses with specific real-time requirements are used. Often, the sensors are connected to these fieldbuses through embedded systems, which also have real-time features specific to the industrial environment in which it operates. The embedded operating systems are very important in the design and development of embedded systems. A distinct class of these operating systems is real-time operating systems (RTOSs) that can be used to develop embedded systems, which have hard and/or soft real-time requirements on small microcontrollers (MCUs). RTOSs offer the basic support for developing embedded systems with applicability in a wide range of fields such as data acquisition, internet of things, data compression, pattern recognition, diversity, similarity, symmetry, and so on. The RTOSs provide basic services for multitasking applications with deterministic behavior on MCUs. The services provided by the RTOSs are task management and inter-task synchronization and communication. The selection of the RTOS is very important in the development of the embedded system with real-time requirements and it must be based on the latency in the handling of the critical operations triggered by internal or external events, predictability/determinism in the execution of the RTOS primitives, license costs, and memory footprint.
    [Show full text]
  • RTEMS Classic API Guide Release 6.7B289f6 (23Th September 2021) © 1988, 2020 RTEMS Project and Contributors
    RTEMS Classic API Guide Release 6.7b289f6 (23th September 2021) © 1988, 2020 RTEMS Project and contributors CONTENTS 1 Preface 3 2 Overview 7 2.1 Introduction......................................8 2.2 Real-time Application Systems............................9 2.3 Real-time Executive.................................. 10 2.4 RTEMS Application Architecture........................... 11 2.5 RTEMS Internal Architecture............................. 12 2.6 User Customization and Extensibility......................... 14 2.7 Portability....................................... 15 2.8 Memory Requirements................................. 16 2.9 Audience........................................ 17 2.10 Conventions...................................... 18 2.11 Manual Organization................................. 19 3 Key Concepts 23 3.1 Introduction...................................... 24 3.2 Objects......................................... 25 3.2.1 Object Names................................. 25 3.2.2 Object IDs................................... 26 3.2.2.1 Object ID Format........................... 26 3.2.3 Object ID Description............................. 26 3.3 Communication and Synchronization........................ 28 3.4 Locking Protocols................................... 29 3.4.1 Priority Inversion............................... 29 3.4.2 Immediate Ceiling Priority Protocol (ICPP)................. 29 3.4.3 Priority Inheritance Protocol......................... 30 3.4.4 Multiprocessor Resource Sharing Protocol (MrsP)............. 30 3.4.5
    [Show full text]
  • Curriculum Vitae
    Giorgiomaria Cicero Curriculum Vitae Embedded Software Engineer Personal Information Address Via Vanella tre, 7 Modica(RG) Italy 97015 Mobile +39 3337229346 email [email protected] Date of birth 18 Jan 1989 Education 2014-2017 Master’s Degree (MSc) Embedded Computing Systems, Scuola Supe- riore Sant’Anna, University of Pisa, Pisa. Real-time operating systems for single-core and multi-core, microprocessors, model- based design, software validation/verification, sensory acquisition and processing, mechatronics, digital control systems, robotics, distributed systems, optimization methods, modelling and timing analysis, advanced human-machine interfaces, virtual and augmented reality, dependable and secure systems Grade 110/110 cum laude Thesis Title A dual-hypervisor for platforms supporting hardware-assisted security and virtualization Supervisors Prof. Giorgio Buttazzo & Dr. Alessandro Biondi 2008-2013 Bachelor’s Degree (BsC) IT Engineer, University of Pisa, Pisa. Algorithms, data bases, programming, software engineering, OSs, logical networks, electronic calculators, digital communications, automation, digital and analogue electronics, applied mechanic Grade 97/110 Thesis Title Embedded signal acquisition, storage and transmission for a rocket powered micro-gravity experiment. Supervisors Prof. Luca Fanucci & Dr. Daniel Cesarini 1/4 Experience 2017-present Research Fellow, Retis lab, Tecip Institute, Scuola Superiore Sant’Anna. Working on solutions for real-time cyber-physical systems, Mixed Independent Levels of Security (MILS) systems, low-level cyber-security. Task covered: { Researching and developing temporal and spatial isolation mechanisms for multi- core platforms. { Development of a safe, secure and hard real-time Type-1 Hypervisor for heteroge- neous platform. { Cyber-security solutions in the automotive field, in collaboration with Magneti Marelli. 2015 Trainee, ESTEC - European Space Agency, Noordwijk, The Netherlands.
    [Show full text]