[mvapich-discuss] xcbrd tests

[Shaun Rowland]

Bas van der Vlies wrote:
> Shaun,
> 
>  First of all we use the same fortran compilers for all the packages 
> that is why we send the results to this list. I will read your web pages 
> and build the libraries as you suggested and let you know what the 
> result is. My question is what version of mvapich2 did you use. we have 
> version 0.9.8 with 4 patches applied.

Do you have separate builds of BLACS, ATLAS, and ScaLAPACK for each of
the MPI implementations and the Fortran compiler used in each? In
addition to the Fortran issue, BLACS and ScaLAPACK also link to the
specific MPI library.

My point about the Fortran compiler possibility was only because I saw
similar problems when I incorrectly built ATLAS with the wrong Fortran
compiler, otherwise I saw no issues with the tests you mentioned. Please
double check the ATLAS package build if you are using that - that seems
to be a possible problem to me. There is a "sanity check" target as
well, to make sure there are no problems with the build. As for the
version of MVAPICH2, I am using the current revision as of today from:

https://mvapich.cse.ohio-state.edu/svn/mpi/mvapich2/branches/0.9.8

which should be revision 1158. We are only applying bug fixes there.

> Which gfortran/gcc version. Ours is  4.1.1

I used gfortran 4.1.0 and gcc version 3.4.6 (this is RHEL AS 4 Update
4). The version difference between the C and Fortran compilers should
not matter in this case, however - I just built with "gcc4" on RHEL 4 as
well, so that gcc and gfortran would both be version 4.1.0. In order to
do this I had to move /usr/bin/gcc out of the way and copy /usr/bin/gcc4
to /usr/bin/gcc because the ATALS build system is, well.. odd. It went
from using the full path I had specified, /usr/bin/gcc4, to just "gcc,"
hence the need to make sure "gcc" was always "gcc4." It also did not
like gcc 4.1.0, but I told it to proceed anyway. I had no problems with
the tests you reported.

The online documentation shows an example of building with gcc and
ifort, and mentions using a non-default Fortran compiler, so using an
alternative Fortran compiler should not be an issue, and again, the only
time the tests you mentioned failed in such a way for me was when I
accidentally built ATLAS with g77 instead of gfortran, while everything
else was built with gfortran, otherwise I made sure the Fortran
compilers were identical in all the packages and had no issues
with those tests. In addition, BLACS and ScaLAPACK were built with the
same MPI implementation's mpicc/mpif77 commands too.

When you build ATLAS, does the sanity check pass all the way when using
gcc 4.1.1 and your chosen Fortran compiler? Note: when I tried forcing
gcc 4.1.0, the ATLAS sanity check did not build properly - which leaves
me at a loss to whether the library is really correct. But, as it seems
from the documentation, building with an alternative Fortran compiler
(using gcc 3.x and gfortran 4.x) should be valid. But, in any case, my
gcc 4.1.0 and gfortran 4.1.0 build did work for MVAPICH2 here. All other
cases I tried were gcc 3.4.6 and gfortran 4.1.0.

> Regards and a happy easter

Thanks, and happy easter to you.
-- 
Shaun Rowland	rowland at cse.ohio-state.edu
http://www.cse.ohio-state.edu/~rowland/