Tools and Benchmarks for Real-Time Systems

Simulation and trace generation • Re: A common input format

2016-07-15T11:25:34+01:00

I am very interested in (1) and (2). During the WATERS discussion, it was clear that there was a lot of terminology clarification going on while you were developing the library. When you have some writing on the matter, please share it here. And if anybody has additional thoughts, it would be good as a starting point for some "terminology standardization" effort.

Statistics: Posted by martinamaggio — Fri Jul 15, 2016

Simulation and trace generation • Re: A common input format

2016-07-11T10:04:26+01:00

Yes, we are defining formal semantics for the terminology of real-time systems. We have built a formal library in Timed Automata, which consists of a set of automata templates, including Task Activation, Job, Scheduler, etc. For example, Task Activation represents the attributes on tasks' activation, including Offset, MinInterval, jitter, etc. The formal library is extensible, as new attributes can be added into a corresponding template. Given a concrete system, a network of Timed Automata is instantiated with the parameters of the system. Then the WCRT of each task can be computed through model checking. Other properties can also be computed, such as the number of deadline misses. In summary, the formal library serves three purposes: (1) as the formal semantics of the existing terminology; (2) as a modular and extensible framework for incorporating new terminology; (3) as a framework to facilitate exact schedulability analysis through model checking.

Statistics: Posted by iceslj — Mon Jul 11, 2016

Simulation and trace generation • Re: A common input format

2016-07-05T13:27:21+01:00

During WATERS'16 there was a mention of updates on this topic. It seems that there is something interesting to discuss, as there was a need (for example) to clarify terminology used differently. Any updates on the initiative?

Statistics: Posted by martinamaggio — Tue Jul 05, 2016

Simulation and trace generation • The MAST model as an input formalism for simulation and response time analysis tools.

2016-02-04T20:57:41+01:00

Dear all,

There are many ways to do simulation. For those who may see it as a way to observe emergent behavior of a system whose timing models can be extracted and used to get some data about the response times for its tasks, let me comment that the imput model of MAST (a suite of tools for doing response time analysis through schedulability analysis) can also be used for this kind of simulation.

If you like you are invited to use the MAST topic to discuss, exchange ideas and evaluate the usage of its input meta-model/schema/format as a means to collect and compare design intents expressed in terms of their relevant timing models. The underlying meta-model for these timing models is very close to the one used in the UML profile for MARTE, though it can be expressed in a much simpler way. The concrete formats available include an ad-hoc text file, an equivalent XML textual representation, and the XMI of the corresponding ecore meta-model.

The MAST model scales very well from simple single-processor tasking models to fully distributed chains of tasks with or without precedence relationships. It includes forks, joins, branch and merges, delays, offsets, shared resources, hierarchical scheduling, and most of the analysable scheduling policies, RT network protocols, and protection protocols. As I mentioned it is used to do response time analysis by means of both, schedulability analysis, and simulation tools.

If there is interest on it, in a next post we can make a quick rational for its structure and present some flexibility concerns.

To get a closer look please check the MAST documentation (http://mast.unican.es).
Please refer to the MAST description document (http://mast.unican.es/mast_description.pdf) to get a better view of the elements that form the timing models in MAST.

Statistics: Posted by medinajl — Thu Feb 04, 2016

Simulation and trace generation • Cyber-Physical Action Language (CPAL): A tool to model, simulate, verify and program Cyber-Physical Systems

2016-01-14T15:06:06+01:00

CPAL is an acronym for the Cyber-Physical Action Language. CPAL is meant to model, simulate, verify and program Cyber-Physical Systems (CPS) which are the types of embedded systems that can be found in cars, planes, robots, UAV, medical devices, home appliance, factory and home automation, power production and distribution, Internet of Things, etc.

CPAL serves to describe both the functional behaviour of the functions, that is their code, as well as the functional architecture of the system (i.e., the set of functions, how they are activated, and the data ﬂow among the functions). CPAL is a formal language in the sense that it has well deﬁned concepts of states and transitions, but CPAL purposely does not provide constructs that are hard to handle, or lead to convoluted code.

CPAL serves two use-cases:

a design exploration platform for CPS with main features being the formal description, the edition, graphical representation and simulation of CPS models,
a real-time execution engine: the vision behind CPAL is that programs can be executed and veriﬁed in simulation mode on a workstation and the exact same code can be later run on an embedded board with the same run-time timing behaviour.

Website and Distribution
See http://www.designcps.com/ for more details.

Statistics: Posted by SebastianAltmeyer — Thu Jan 14, 2016

Simulation and trace generation • Re: A common input format

2015-11-19T08:19:35+01:00

Hi everybody,

Very interesting initiative.
In our SchedMCore tool we use a relatively simple text task file format (TFF).
You'll find our usage description in the file attached to the current post.

--
Eric NOULARD, ONERA/DTIM/LAPS, ONERA - Centre de Toulouse
http://www.onera.fr/dtim
2 avenue E. Belin, B.P. 74025, F-31055 Toulouse Cedex 4, FRANCE
tel: +33 (0)5 62 25 26 38, fax: +33 (0)5 62 25 25 93

lsmc-TN002-taskfileformat.pdf

Statistics: Posted by erk — Thu Nov 19, 2015

Simulation and trace generation • SchedMCore: Multi/Many core scheduling analysis and simulation tools

2015-11-19T08:05:37+01:00

Description of the tool
SchedMCore is an Open Source library and a set of tools made by ONERA (The French Aerospace Labs, http://www.onera.fr) for experimenting real-time scheduling analysis and programming. The main features of SchedMCore are:

A schedulability model generator: the generator takes a periodic tasks set description and a scheduling policy as input and generates a formal model (currently either in C or Uppaal) which may be used to proceed to a multi-processor schedulability analysis.
A real-time simulation library including a scheduler plugins architecture which may be used to test-drive a scheduler policy on a RT-POSIX compliant system (currently working on standard Linux).

Usage scope
Multi/Many-core schedulability analysis and simulation.

People
Claire Pagetti - ONERA Centre de Toulouse
Eric Noulard - ONERA Centre de Toulouse

Link to the website
More informations there: http://sites.onera.fr/schedmcore/node/1
Forge, https://forge.onera.fr/projects/schedmcore, and source code repository, https://svn.onera.fr/schedmcore, are available as well.

Version History
Please check http://sites.onera.fr/schedmcore/node/1
or directly the subversion history; https://svn.onera.fr/schedmcore

--
Eric NOULARD, ONERA/DTIM/LAPS, ONERA - Centre de Toulouse
http://www.onera.fr/dtim
2 avenue E. Belin, B.P. 74025, F-31055 Toulouse Cedex 4, FRANCE
tel: +33 (0)5 62 25 26 38, fax: +33 (0)5 62 25 25 93

Statistics: Posted by erk — Thu Nov 19, 2015

Simulation and trace generation • Re: A common input format

2015-11-18T17:07:42+01:00

Hi Olivier,

Thanks for getting the discussion started! Could you edit your post to add links to the websites of the tools you mention? That'd be really helpful. I know some of them but not all.

Thanks,
Sophie

Statistics: Posted by Sophie Quinton — Wed Nov 18, 2015

Simulation and trace generation • Re: A common input format

2015-11-18T12:59:29+01:00

Hello,

As a basical state of the art to improve this topic, I started to build a list of already well-known existing real-time simulation tools, in order to focus particularly on the way they modelize input and output informations. I splitted, for now, tools in two parts : processor-oriented, and network-oriented. Currently, I obtained the following informations for processor-oriented tools (tool/input-output modelization/development language) :

Cheddar - XML/AADL - Ada
Fortas - XML - Java
SimSo - Python - Python
Yartiss - XML - Java
TimeWiz - Unknown - Unknown
RapidRM - Unknown - Unknown
MAST - MARTE/XSD - Unknown
CPAL - Unknown - Unknow

I suggest from all the users and readers to contact me about this subject (cros@ece.fr), if you want to ask me questions or to bring some more informations about tools you use or develop inside a specific RT context. I'll be please to add your tool to this list or to precise already existing informations.

The main purpose is to build, first, a global view of each way of modelizing datas in different RT simulation tools, in order to focus on the specifical needs of each and then to integrate these needs inside a common input format.

Statistics: Posted by oliviercros — Wed Nov 18, 2015

Simulation and trace generation • A common input format

2015-11-17T13:17:57+01:00

At WATERS'15 we had a lengthy discussion about a common input format for simulation tools. This topic is meant for discussing this issue. Share your experience/opinion/proposal!

Best,
Sophie

Statistics: Posted by Sophie Quinton — Tue Nov 17, 2015

Simulation and trace generation • Re: Simso: Simulation of Multiprocessor Scheduling Algorithms with Overheads

2015-09-14T06:47:32+01:00

It runs as a full-client application (no server-side) written in javascript, and uses PypyJS (a javascript implementation of Pypy) to run Python in order to execute SimSo.

Nice. I personally like the idea very much and the interface is well realized.
Do you plan in some way to give information about deadline misses? It would be nice for example to draw red arrows for deadlines that are missed.

Statistics: Posted by martinamaggio — Mon Sep 14, 2015

Simulation and trace generation • Re: Simso: Simulation of Multiprocessor Scheduling Algorithms with Overheads

2015-09-04T21:19:26+01:00

A new tool is available: SimSoWeb is a full browser interface which provides a simple and intuitive graphical interface that aims at helping you discover the core features of Simso. It runs as a full-client application (no server-side) written in javascript, and uses PypyJS (a javascript implementation of Pypy) to run Python in order to execute SimSo.

Link: http://projects.laas.fr/simso/simso-web/

Statistics: Posted by hladik — Fri Sep 04, 2015

Simulation and trace generation • Simso: Simulation of Multiprocessor Scheduling Algorithms with Overheads

2015-07-21T17:18:58+01:00

Description of the tool

SimSo is a scheduling simulator for real-time multiprocessor architectures that takes into account some scheduling overheads (scheduling decisions, context switches) and the impact of caches through statistical models. Based on a Discrete-Event Simulator (SimPy), it allows quick simulations and a fast prototyping of scheduling policies using Python. Currently, more than 25 popular schedulers are available.

Since SimSo 0.7 (April 2015), SimSo is divided in 2 components: the core and the graphical user interface

Usage scope

Simulation of scheduling policies taking into account cache and scheduling overheads

People
- Pierre-Emmanuel Hladik (LAAS CNRS)

Links
- http://projects.laas.fr/simso/

Release history

Latest release is SimSo 0.7 (April 2015); For Windows users that don't want to install Python and PyQt, you can install SimSo using a Windows Executable Binary http://projects.laas.fr/simso/setup_simso.exe (SimSo 0.8.2)

Statistics: Posted by dalzilio — Tue Jul 21, 2015

Simulation and trace generation • hsSim: an Extensible Interoperable Object-Oriented n-Level Hierarchical Scheduling Simulator

2015-07-02T13:16:50+01:00

Description of the tool
hsSim is a multiprocessor hierarchical scheduling simulator, written in Java with due care to modularity, extendability and interoperability. Its initial development was presented at WATERS 2012, in Pisa.

Usage scope
Hierarchical scheduling is a recent real-time scheduling topic. It is used to obtain temporal interference isolation in various scenarios, such as scheduling soft real-time aperiodic tasks along with hard real-time periodic tasks, and in mixed-criticality scenarios. Most theory and practice focuses on two-level hierarchies, with a root (global) scheduler managing resource contention by partitions (or scheduling servers), and a local scheduler in each partition/server to schedule the respective tasks. hsSim is an object-oriented hierarchical scheduling simulator supporting an arbitrary number of levels. With the goal of openness, extensibility and interoperability in mind, due care was put into the design, applying known design patterns where deemed advantageous.

People
- João Craveiro (Premium Minds/University Lusófona, work developed at LaSIGE - Lisbon, Portugal)

Links
- Code: github
- Paper: J. P. Craveiro, R. O. Silveira, and J. Rufino, “hsSim: an Extensible Interoperable Object-Oriented n-Level Hierarchical Scheduling Simulator,” in 3rd International Workshop on Analysis Tools and Methodologies for Embedded and Real-time Systems (WATERS 2012), Pisa, Italy, Jul. 2012.

Work in progress
...

Release history
...

Statistics: Posted by jcraveiro — Thu Jul 02, 2015

Simulation and trace generation • TrueTime: Simulation of Networked and Embedded Control Systems

2015-06-24T16:03:56+01:00

Description of the tool
TrueTime is a Matlab/Simulink-based simulator for real-time control systems. TrueTime facilitates co-simulation of controller task execution in real-time kernels, network transmissions, and continuous plant dynamics.

Usage scope
Simulation of dynamical systems and scheduling policies

People
- Anton Cervin (Lund University)

Links
- Website: website

Work in progress
2015.06.30 - To be defined

Release history
2012.04.27 - TrueTime 2.0 beta 7 has been released.

Statistics: Posted by admin — Wed Jun 24, 2015