Commit 22f953fa authored by Tomas Härdin's avatar Tomas Härdin

Type, subsection on MPI world size

parent 88c6c84b
Pipeline #1101 failed with stages
in 0 seconds
......@@ -174,7 +174,7 @@
<!-- http://umu.diva-portal.org/smash/record.jsf?pid=diva2%3A140361&dswid=-8713 -->
<a href="SPOOK.pdf">SPOOK solver by Claude Lacoursière</a>.
Another option is to use the NEPCE method developed by Edo Drenth,
which involves adding sinc² filters to FMU outputs and adding striff springs+dampers to relevant inputs.
which involves adding sinc² filters to FMU outputs and adding stiff springs+dampers to relevant inputs.
Some of that work can be automated using our ME→CS FMU wrapper tool.
Using special purpose solvers may also be necessary, such as exponential integrators.
FMIGo! does not provide this, unless GSL does.
......@@ -272,6 +272,24 @@
Keep in mind that kinematic coupling allows the system to take much larger simulation time steps,
which results in overall better performance for many systems.
</p>
<h2>MPI world size / backend network shape</h2>
<p>
At the moment the size of the MPI world must be the number of FMUs plus one.
This because each server only serves a single FMU, and the master is its own node.
The situation is similar when using TCP/IP (ZMQ) communication.
</p>
<p>
This MPI world / network shape increases overhead compared to using OpenMP
or pthreads for communicating between FMUs running on the same CPU.
Ideally the world size would be exactly the same as the ideal number of CPUs required
for running all FMUs plus the solver.
Getting that right is somewhat complicated,
which is why we've left it out for now.
</p>
<p>
Going to a federated system is perhaps an even better way to deal with this problem.
This is something we have in mind for a potential continuation of the project.
</p>
<h2>Authoring tools</h2>
<p>
FMIGo! has very little in the form of authoring tools.
......@@ -358,6 +376,7 @@
<h1 id="news">News</h1>
<h2>2018-11-07</h2>
<p>Domain fmigo.net registered, site published at <a href="http://www.fmigo.net/">http://www.fmigo.net/</a>.</p>
<p>Added a subsection on MPI world size.</p>
<h2>2018-11-02</h2>
<p>First draft of the site published.</p>
</section>
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment