Docs:   Installation: UNIX

Required Software:

Prior to installing PETSc, the machine must have:

• An implementation of MPI. Parallel machines come with one provided by the vendors; check with your support staff. We recommend using the vendor-provided implementation of MPI if it has been installed, since this usually provides better performance than the freeware versions. Otherwise, we recommend MPICH, which is available at http://www.mcs.anl.gov/mpi/mpich. If MPI is not yet installed on your system, retrieve a version of MPI, install it, and run the example programs before proceeding further. 

  For users who are interested ONLY in running PETSc sequentially, we have included a stripped-down version of MPI that allows PETSc to be compiled without installing an external version of MPI. This setup allows the user to run ONLY uniprocessor PETSc  programs, not parallel ones.

• A copy of the BLAS and LAPACK. Many machines provide math libraries that contain BLAS or LAPACK. For example, the DEC alpha provides DXML, and the IBM rs6000 provides ESSL. Check with your support staff. The BLAS library on some machines may be found as /usr/lib/libblas.a. If these libraries are not already installed on the target architecture, they can be obtained from  ftp://ftp.mcs.anl.gov/pub/petsc/fblaslapack.tar.gz. We recommend using the vendor-provided BLAS when possible.

Optional Packages:

PETSc provides an interface to several software packages.. These should be installed before installing PETSc. These packages are not developed, maintained, or supported by the PETSc team; we merely provide an interface to them. More details on installing for optional packages.

Installing PETSc:

• Obtain the installation file.
• The PETSc distribution can be unbundled with
     gunzip -c petsc.tar.gz | tar xof -
  By default, this will create a directory called petsc-2.1.5 and unpack the software there.
• Refer to http://www.mcs.anl.gov/petsc/petsc-patches.html for fixes for the latest PETSc release.
• Set the environmental variable PETSC_DIR to the full path of the PETSc home directory, for example,
     setenv PETSC_DIR /home/username/petsc-2.1.5
• Set the environmental variable PETSC_ARCH, which indicates the architecture on which PETSc will be configured. For example, use
     setenv PETSC_ARCH  solaris_gnu
     setenv PETSC_ARCH rs6000_sp
     setenv PETSC_ARCH  `$PETSC_DIR/bin/petscarch`
  Note that using the petscarch command will only work if you are using the default installation compilers on your machine.
• Edit the file ${PETSC_DIR}/bmake/${PETSC_ARCH}/packages to indicate the local installation of MPI, LAPACK, BLAS, X-windows, and the optional software packages. More details on installing for optional packages.

  Note: If installing ONLY a uniprocessor version of PETSc, then installation of an MPI implementation is not required. Instead, the following MPI locations can be used in the ${PETSC_DIR}/bmake/${PETSC_ARCH}/packages file:
     MPI_LIB = ${PETSC_DIR}/lib/lib${BOPT}/${PETSC_ARCH}/libmpiuni.a
     MPI_INCLUDE = -I${PETSC_DIR}/src/sys/src/mpiuni
     MPIRUN = ${PETSC_DIR}/src/sys/src/mpiuni/mpirun

• It may also be necessary to edit the following file   ${PETSC_DIR}/bmake/${PETSC_ARCH}/variables to change the names of the C, C++, or Fortran compilers from their defaults:

• Solaris using the GNU compilers: use PETSC_ARCH=solaris_gnu
• IBM rs6000 using the GNU compilers: use PETSC_ARCH=rs6000_gnu
• CRAY t3d: make sure the enviornmental variable TARGET is set to cray-t3d

• In the PETSc home directory, type
     make BOPT=g all >& make_log
  to build a debugging version of the PETSc or
     make BOPT=O all >& make_log
  to build optimized version of the PETSc libraries. The flag BOPT determines what type of libraries are built (i.e., specifies compiler options). The other alternatives are BOPT=[g_c++,O_c++] for C++ versions and BOPT=[g_complex,O_complex] for complex numbers versions.

  On HP-UX machines we highly recommend using Gnu make (which can be installed if not already available) rather than the native make. To switch to using gnumake in the PETSc makefiles, define OMAKE to be the path of gnumake in the file ${PETSC_DIR}/bmake/hpux/base.

• Check make_log to determine whether any errors have occured during the installation process. Try to fix any errors, and let us know what they were. But first see the files troubleshooting.html , http://www.mcs.anl.gov/petsc/petsc-patches.html and bug reporting for help with common problems.

Installing PETSc using configure:

Please check our updated instructions on using confiugre with PETSc.

Test programs:

• If the installation went smoothly, then try running some test examples with the command
     make BOPT=g testexamples >& examples_log 
• If only the uniprocessor version of PETSc has been installed (i.e., MPI has not been installed), then use the following command to run only sequential examples:
     make BOPT=g testexamples_uni >& examples_log
• Examine the file examples_log for any obvious errors or problems.
• The examples can be manually built and run one at a time by changing to the appropriate directory (for instance, ${PETSC_DIR}/src/sles/examples/tutorials) and running commands such as
     make BOPT=g ex1
     make runex1 (or, for example, mpirun ex1)
  This alternative may be preferable if "make BOPT=g testexamples" fails for some reason.
• The automatic tests may not work on systems that use a queue and special commands to run parallel jobs.  Instead, the user can compile and run the examples manually as discussed above.
• To test the graphics examples, move to ${PETSC_DIR}/src/sys/src/draw/examples/tests; then make and run the examples manually. These examples will open an X window and draw some graphics.

Fortran Users:

The PETSc Fortran libraries are built automatically during the installation outlined above. Before testing the fortran examples, please make sure that the c-version of the examples work correctly.

• To compile and test the Fortran examples, use the command
     make BOPT=g testfortran >& fortran_log

PETSc Fortran programs should use the suffix .F rather than the traditional suffix .f, so that the PETSc header files can be easily included in Fortran programs, and processed by a c-preprocessor. See the Fortran chapter within the users manual for additional details regarding the Fortran interface.

Multiple Installations:

When building PETSc for two or more machine types that share a common filesystem, for example sun4 and hpux, multiple PETSc directory trees are NOT needed. Only a single PETSc directory can (and should) be used; PETSc automatically places the libraries for each machine in a different location. In particular, the libraries for a given BOPT and PETSC_ARCH are installed in the directory, ${PETSC_DIR}/lib/lib${BOPT}/${PETSC_ARCH}.

Shared Libraries:

PETSc supports the use of shared libraries for the machines  solaris, alpha, IRIX, IRIX64, freebsd, and linux to enable faster linking and smaller executables.  These libraries are built automatically during installation. In addition, PETSc now defaults to using these libraries as dynamic libraries on these machines. For most users this does not matter. 

Machines without Fortran compiler:

On machines that do not have a fortran compiler, like BeOS, MacOS-X, please download and install f2c version of blas and lapack - f2cblaslapack.tar.gz.

Special Blas and Lapack.

Some machines have special blas and lapack.  These have some missing symbols missing or define prototypes for certain functions differently.

When using ESSL on AIX machines, you might want to use the following additional flag in 'packages file'

BLASLAPACK_LIB = -lessl
PETSC_BLASLAPACK_FLAGS = -DPETSC_BLASLAPACK_ESSL_ONLY
PETSC_HAVE_ESSL = -DPETSC_HAVE_ESSL
 

When using cray T3E use:

BLASLAPACK_LIB =
PETSC_BLASLAPACK_FLAGS = -DPETSC_BLASLAPACK_CRAY_ONLY