]> https://gitweb.dealii.org/ - dealii.git/commitdiff
Add a warning against using --download-mpich. 2828/head
authorDavid Wells <wellsd2@rpi.edu>
Thu, 14 Jul 2016 21:16:44 +0000 (17:16 -0400)
committerDavid Wells <wellsd2@rpi.edu>
Fri, 15 Jul 2016 00:54:45 +0000 (20:54 -0400)
This is a PETSc option that usually causes trouble, especially when a
user already has MPI installed on their machine.

doc/external-libs/petsc.html

index 10a92ab7b7c1e2c3af2d14c7f664fe247020bc20..78b75b2762a3864055f1104066acf43702413667 100644 (file)
 
     <p>
       This automatically builds PETSc with both MPI and the algebraic
-      multigrid preconditioner package Hypre (which we use in step-40).
+      multigrid preconditioner package Hypre (which we use in step-40). If you
+      would like to use PETSc with MPI then we recommend that you install MPI
+      through your package manager instead of letting PETSc install it: put
+      another way, installing PETSc with the flag <code>--download-mpich</code>
+      often causes problems (such as linking errors or poor performance)
+      that may be avoided by using whatever your system provides instead.
       <br>
       Now let PETSc check his own sanity:
       <pre>

In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move.

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