Using existing mpich for new built

[Satish Balay]

On Mon, 7 May 2007, Ben Tay wrote:

> In that case, can I use the this mpich library for other builds of PETSc on
> the same system? For e.g., I have 2 builts, 1 with external solver like
> hypre, another without. Can I use the same mpich built for the 2nd PETSc
> after I had the 1st PETSc library compiled?
> 
> Similarly, can I reuse the blas/lapack compiled for the 1st built?

yeah - you could - but why bother? It just complicates things.

I guess the reason you've used --download-mpich=1 [instead of
installing mpich separately] is to keep the install process simple. So
just do the same thing for the second install as well.

./config/configure.py --download-mpich=1 --download-f-blas-lapack=1 PETSC_ARCH=linux-nohypre
./config/configure.py --download-mpich=1 --download-f-blas-lapack=1 --download-hypre=1 PETSC_ARCH=linux-hypre

Alternatively - if you don't want multiple copies of each of these
packages, then install them first [separately] and then specify them
to PETSc.

./config/configure.py --with-mpi-dir=/home/balay/soft/mpich --with-blas-lapack-dir=/home/balay/soft/blaslapack PETSC_ARCH=linux-nohypre
./config/configure.py --with-mpi-dir=/home/balay/soft/mpich --with-blas-lapack-dir=/home/balay/soft/fblaslapack --download-hypre=1  PETSC_ARCH=linux-hypre

> What are the options?

If you wish to reuse the install of externalpackages from one build
over to the next one, you can do the following. [However you should
keep track of this dependency when you attempt to rebuild stuff]

./config/configure.py --download-mpich=1 --download-f-blas-lapack=1 PETSC_ARCH=linux-nohypre
./config/configure.py --with-mpi-dir=`pwd`/externalpackages/mpich2-1.0.4p1/linux-nohypre --with-blas-lapack-dir=`pwd`/externalpackages/fblaslapack/linux-nohypre --download-hypre=1  PETSC_ARCH=linux-hypre

Satish