X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/5eca6390609ff027f63cbd6480aef17b1daa17b9..73f144ee8a0ad34297c50e8b2613e0cb64c54a00:/docs/source/Tutorial_MPI_Applications.rst

diff --git a/docs/source/Tutorial_MPI_Applications.rst b/docs/source/Tutorial_MPI_Applications.rst
index 703f4ee94c..eae9d38532 100644
--- a/docs/source/Tutorial_MPI_Applications.rst
+++ b/docs/source/Tutorial_MPI_Applications.rst
@@ -13,7 +13,7 @@ C/C++/F77/F90 applications should run out of the box in this
 environment. In fact, almost all proxy apps provided by the `ExaScale
 Project <https://proxyapps.exascaleproject.org/>`_ only require minor
 modifications to `run on top of SMPI
-<https://github.com/simgrid/SMPI-proxy-apps/>`_.
+<https://framagit.org/simgrid/SMPI-proxy-apps>`_.
 
 This setting permits to debug your MPI applications in a perfectly
 reproducible setup, with no Heisenbugs. Enjoy the full Clairevoyance
@@ -81,21 +81,30 @@ examples.
 Simple Example with 3 hosts
 ...........................
 
-At the most basic level, you can describe your simulated platform as a
-graph of hosts and network links. For instance:
+Imagine you want to describe a little platform with three hosts,
+interconnected as follows:
 
 .. image:: /tuto_smpi/3hosts.png
    :align: center
 
+This can be done with the following platform file, that considers the
+simulated platform as a graph of hosts and network links.
+
 .. literalinclude:: /tuto_smpi/3hosts.xml
    :language: xml
 
-Note the way in which hosts, links, and routes are defined in
-this XML. All hosts are defined with a speed (in Gflops), and links
-with a latency (in us) and bandwidth (in MBytes per second). Other
-units are possible and written as expected. Routes specify the list of
-links encountered from one route to another. Routes are symmetrical by
-default.
+The elements basic elements (with :ref:`pf_tag_host` and
+:ref:`pf_tag_link`) are described first, and then the routes between
+any pair of hosts are explicitely given with :ref:`pf_tag_route`. 
+
+Any host must be given a computational speed in flops while links must
+be given a latency and a bandwidth. You can write 1Gf for
+1,000,000,000 flops (full list of units in the reference guide of 
+:ref:`pf_tag_host` and :ref:`pf_tag_link`). 
+
+Routes defined with :ref:`pf_tag_route` are symmetrical by default,
+meaning that the list of traversed links from A to B is the same as
+from B to A. Explicitely define non-symmetrical routes if you prefer.
 
 Cluster with a Crossbar
 .......................
@@ -303,8 +312,8 @@ Debian and Ubuntu for example, you can get them as follows:
 
    sudo apt install simgrid pajeng make gcc g++ gfortran vite
 
-For R analysis of the produced traces, you may want to install R, 
-and the `pajengr<https://github.com/schnorr/pajengr#installation/>`_ package.
+For R analysis of the produced traces, you may want to install R,
+and the `pajengr <https://github.com/schnorr/pajengr#installation/>`_ package.
 
 .. code-block:: shell
 
@@ -481,7 +490,7 @@ is computationally hungry.
     the documentation is up-to-date.
 
 Lab 3: Execution Sampling on Matrix Multiplication example
--------------------------------
+----------------------------------------------------------
 
 The second method to speed up simulations is to sample the computation
 parts in the code.  This means that the person doing the simulation
@@ -500,13 +509,12 @@ The computing part of this example is the matrix multiplication routine
 .. literalinclude:: /tuto_smpi/gemm_mpi.cpp
    :language: c
    :lines: 4-19
-   
 
 .. code-block:: shell
 
   $ smpicc -O3 gemm_mpi.cpp -o gemm
   $ time smpirun -np 16 -platform cluster_crossbar.xml -hostfile cluster_hostfile --cfg=smpi/display-timing:yes --cfg=smpi/running-power:1000000000 ./gemm
-  
+
 This should end quite quickly, as the size of each matrix is only 1000x1000. 
 But what happens if we want to simulate larger runs ?
 Replace the size by 2000, 3000, and try again.
@@ -580,7 +588,7 @@ so these macros cannot be used when results are critical for the application beh
 
 
 Lab 4: Memory folding on large allocations
--------------------------------
+------------------------------------------
 
 Another issue that can be encountered when simulation with SMPI is lack of memory.
 Indeed we are executing all MPI processes on a single node, which can lead to crashes.
@@ -618,8 +626,8 @@ Further Readings
 
 You may also be interested in the `SMPI reference article
 <https://hal.inria.fr/hal-01415484>`_ or these `introductory slides
-<http://simgrid.org/tutorials/simgrid-smpi-101.pdf>`_. The `SMPI
-reference documentation <SMPI_doc>`_ covers much more content than
+<http://simgrid.org/tutorials/simgrid-smpi-101.pdf>`_. The :ref:`SMPI
+reference documentation <SMPI_doc>` covers much more content than
 this short tutorial.
 
 Finally, we regularly use SimGrid in our teachings on MPI. This way,