-.. First introduction
+.. _intro_concepts:
-What is SimGrid
-===============
-
-SimGrid is a framework to simulate distributed computer systems.
-
-It can be used to either assess abstract algorithms or to profile and
-debug real distributed applications. SimGrid enables studies in the
-domains of (data-)Grids, IaaS Clouds, Clusters, High Performance
-Computing, Volunteer Computing, and Peer-to-Peer systems.
-
-Technically speaking, SimGrid is a library. It is neither a graphical
-interface nor a command-line simulator running user scripts. The
-interaction with SimGrid is done by writing programs with the exposed
-functions to build your own simulator.
-
-SimGrid is a Free Software distributed under the LGPLv3 license. You are
-thus welcome to use it as you wish or even to modify and distribute
-your version (provided that your version is as free as ours). It also
-means that SimGrid is developed by a vivid community of users and
-developers. We hope that you will come and join us!
-
-SimGrid is the result of almost 20 years of research from several
-groups, both in France and in the U.S.A. It benefited of many funding
-from various research bodies, including the ANR, Inria, CNRS,
-University of Lorraine, University of Hawai'i at Manoa, ENS Rennes, and
-many others. Many thanks to our generous sponsors!
-
-SimGrid is a powerful tool, but its learning curve can be rather
-steep. This manual will hopefully help and guide you to the features
-you want to use. Please report any issue that you see in this manual,
-including typos or unclear elements. You can even propose changes by
-clicking on the "Edit on GitLab" button at the top of every page.
+Main Concepts
+=============
Typical Study based on SimGrid
------------------------------
parallel application using for example the MPI interface
:ref:`(more info) <application>`.
- - The **Virtual Platform**. This is a description of a given
+ - The **Simulated Platform**. This is a description of a given
distributed system (machines, links, disks, clusters, etc). Most of
the platform files are written in XML althrough a Lua interface is
- under development. SimGrid makes it easy to augment the Virtual
+ under development. SimGrid makes it easy to augment the Simulated
Platform with a Dynamic Scenario where for example the links are
slowed down (because of external usage) or the machines fail. You
have even support to specify the applicative workload that you want
- The application's **Deployment Description**. In SimGrid
terminology, the application is an inert set of source files and
binaries. To make it run, you have to describe how your application
- should be deployed on the virtual platform. You need to specify
+ should be deployed on the simulated platform. You need to specify
which process is mapped on which machine, along with their parameters
:ref:`(more info) <scenario>`.
- - The **Platform Models**. They describe how the virtual platform
+ - The **Platform Models**. They describe how the simulated platform
reacts to the actions of the application. For example, they compute
- the time taken by a given communication on the virtual platform.
+ the time taken by a given communication on the simulated platform.
These models are already included in SimGrid, and you only need to
pick one and maybe tweak its configuration to get your results
:ref:`(more info) <models>`.
they contribute to compares to the existing solutions from the
literature.
- - **Design the best Virtual Platform for a given Application.**
+ - **Design the best [Simulated] Platform for a given Application.**
Tweaking the platform file is much easier than building a new real
platform for testing purpose. SimGrid also allows for the co-design
of the platform and the application by modifying both of them.
Depending on the intended study, SimGrid can be run in several execution modes.
**Simulation Mode**. This is the most common execution mode, where you want
-to study how your application behaves on the virtual platform under
+to study how your application behaves on the simulated platform under
the experimental scenario.
In this mode, SimGrid can provide information about the time taken by
each computation kernel only once, save on disk the time it takes and
some other metadata. This code block can then be skipped in simulation
and replaced by a synthetic block using the cached information. The
-virtual platform will take this block into account without requesting
+simulated platform will take this block into account without requesting
the real hosting machine to benchmark it.
SimGrid Limits
Some of these applications enjoy large user communities themselves.
.. LocalWords: SimGrid
+
