3 Configuring and Building AMG4PSBLAS

In order to build AMG4PSBLAS it is necessary to set up a Makefile with appropriate system-dependent variables; this is done by means of the configure script. The distribution also includes the autoconf and automake sources employed to generate the script, but usually this is not needed to build the software.

AMG4PSBLAS is implemented almost entirely in Fortran 2003, with some interfaces to external libraries in C; the Fortran compiler must support the Fortran 2003 standard plus the extension MOLD= feature, which enhances the usability of ALLOCATE. Most Fortran compilers provide this feature; in particular, this is supported by the GNU Fortran compiler, for which we recommend to use at least version 4.8. The software defines data types and interfaces for real and complex data, in both single and double precision.

Building AMG4PSBLAS requires some base libraries (see Section 3.1); interfaces to optional third-party libraries, which extend the functionalities of AMG4PSBLAS (see Section 3.2), are also available. A number of Linux distributions (e.g., Ubuntu, Fedora, CentOS) provide precompiled packages for the prerequisite and optional software. In many cases these packages are split between a runtime part and a “developer” part; in order to build AMG4PSBLAS you need both. A description of the base and optional software used by AMG4PSBLAS is given in the next sections.

3.1 Prerequisites

The following base libraries are needed:

BLAS

[18, 19, 26] Many vendors provide optimized versions of BLAS; if no vendor version is available for a given platform, the ATLAS software (math-atlas.sourceforge .net) may be employed. The reference BLAS from Netlib (www.netlib.org/blas) are meant to define the standard behaviour of the BLAS interface, so they are not optimized for any particular platform, and should only be used as a last resort. Note that BLAS computations form a relatively small part of the AMG4PSBLAS/PSBLAS; however they are critical when using preconditioners based on the MUMPS, UMFPACK or SuperLU third party libraries. UMFPACK requires a full LAPACK library; our experience is that configuring ATLAS for building full LAPACK does not always work in the expected way. Our advice is first to download the LAPACK tarfile from www.netlib.org/lapack and install it independently of ATLAS. In this case, you need to modify the OPTS and NOOPT definitions for including -fPIC compilation option in the make.inc file of the LAPACK library.

MPI

[25, 32] A version of MPI is available on most high-performance computing systems.

PSBLAS

[21, 23] Parallel Sparse BLAS (PSBLAS) is available from psctoolkit.github.io/ products/psblas/; version 3.7.0 (or later) is required. Indeed, all the prerequisites listed so far are also prerequisites of PSBLAS.

Please note that the four previous libraries must have Fortran interfaces compatible with AMG4PSBLAS; usually this means that they should all be built with the same compiler being used for AMG4PSBLAS.

If you want to use the PSBLAS support for NVIDIA GPUs, you will also need a working version of the CUDA Toolkit that is compatible with the compiler choice made to compile PSBLAS and AMG4PSBLAS. After that you will need to have configured and compiled the PSBLAS library with the options:

./configure --enable-cuda --with-cudadir=${CUDA_HOME} --with-cudacc=xx,yy,zz

Previous versions required you to have the auxiliary libraries SPGPU and PSBLAS-EXT compiled, this is no longer necessary because they have been integrated into PSBLAS and are compiled by activating the previous flags during configuration. See also Sec 4.2.

3.2 Optional third party libraries

We provide interfaces to the following third-party software libraries; note that these are optional, but if you enable them some defaults for multilevel preconditioners may change to reflect their presence.

UMFPACK

[16] A sparse LU factorization package included in the SuiteSparse library, available from faculty.cse.tamu.edu/davis/suitesparse.html; it provides sequential factorization and triangular system solution for double precision real and complex data. We tested version 4.5.4 of SuiteSparse. Note that for configuring SuiteSparse you should provide the right path to the BLAS and LAPACK libraries in the SuiteSparse_config/SuiteSparse_config.mk file.

MUMPS

[2] A sparse LU factorization package available from mumps.enseeiht.fr; it provides sequential and parallel factorizations and triangular system solution for single and double precision, real and complex data. We tested versions 4.10.0 and 5.0.1.

SuperLU

[17] A sparse LU factorization package available from crd.lbl.gov/~xiaoye/SuperLU/; it provides sequential factorization and triangular system solution for single and double precision, real and complex data. We tested versions 4.3 and 5.0. If you installed BLAS from ATLAS, remember to define the BLASLIB variable in the make.inc file.

SuperLU_Dist

[28] A sparse LU factorization package available from the same site as SuperLU; it provides parallel factorization and triangular system solution for double precision real and complex data. We tested versions 3.3 and 4.2. If you installed BLAS from ATLAS, remember to define the BLASLIB variable in the make.inc file and to add the -std=c99 option to the C compiler options. Note that this library requires the ParMETIS library for parallel graph partitioning and fill-reducing matrix ordering, available from glaros.dtc.umn.edu/gkhome/metis/parmetis/overview.

3.3 Configuration options

In order to build AMG4PSBLAS, the first step is to use the configure script in the main directory to generate the necessary makefile.

As a minimal example consider the following:

./configure --with-psblas=PSB-INSTALL-DIR

which assumes that the various MPI compilers and support libraries are available in the standard directories on the system, and specifies only the PSBLAS install directory (note that the latter directory must be specified with an absolute path). The full set of options may be looked at by issuing the command ./configure --help, which produces:

configure configures AMG4PSBLAS 1.0.0 to adapt to many kinds of systems. 
 
Usage: ./configure [OPTION]... [VAR=VALUE]... 
 
To assign environment variables (e.g., CC, CFLAGS...), specify them as 
VAR=VALUE.  See below for descriptions of some of the useful variables. 
 
Defaults for the options are specified in brackets. 
 
Configuration: 
  -h, --help              display this help and exit 
      --help=short        display options specific to this package 
      --help=recursive    display the short help of all the included packages 
  -V, --version           display version information and exit 
  -q, --quiet, --silent   do not print checking ...’ messages 
      --cache-file=FILE   cache test results in FILE [disabled] 
  -C, --config-cache      alias for ‘--cache-file=config.cache 
  -n, --no-create         do not create output files 
      --srcdir=DIR        find the sources in DIR [configure dir or ‘..’] 
 
Installation directories: 
  --prefix=PREFIX         install architecture-independent files in PREFIX 
                          [/usr/local] 
  --exec-prefix=EPREFIX   install architecture-dependent files in EPREFIX 
                          [PREFIX] 
 
By default, make install will install all the files in 
‘/usr/local/bin’, ‘/usr/local/lib etc.  You can specify 
an installation prefix other than ‘/usr/local using ‘--prefix’, 
for instance ‘--prefix=$HOME’. 
 
For better control, use the options below. 
 
Fine tuning of the installation directories: 
  --bindir=DIR            user executables [EPREFIX/bin] 
  --sbindir=DIR           system admin executables [EPREFIX/sbin] 
  --libexecdir=DIR        program executables [EPREFIX/libexec] 
  --sysconfdir=DIR        read-only single-machine data [PREFIX/etc] 
  --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com] 
  --localstatedir=DIR     modifiable single-machine data [PREFIX/var] 
  --libdir=DIR            object code libraries [EPREFIX/lib] 
  --includedir=DIR        C header files [PREFIX/include] 
  --oldincludedir=DIR     C header files for non-gcc [/usr/include] 
  --datarootdir=DIR       read-only arch.-independent data root [PREFIX/share] 
  --datadir=DIR           read-only architecture-independent data [DATAROOTDIR] 
  --infodir=DIR           info documentation [DATAROOTDIR/info] 
  --localedir=DIR         locale-dependent data [DATAROOTDIR/locale] 
  --mandir=DIR            man documentation [DATAROOTDIR/man] 
  --docdir=DIR            documentation root [DATAROOTDIR/doc/amg4psblas] 
  --htmldir=DIR           html documentation [DOCDIR] 
  --dvidir=DIR            dvi documentation [DOCDIR] 
  --pdfdir=DIR            pdf documentation [DOCDIR] 
  --psdir=DIR             ps documentation [DOCDIR] 
 
Program names: 
  --program-prefix=PREFIX            prepend PREFIX to installed program names 
  --program-suffix=SUFFIX            append SUFFIX to installed program names 
  --program-transform-name=PROGRAM   run sed PROGRAM on installed program names 
 
Optional Features: 
  --disable-option-checking  ignore unrecognized --enable/--with options 
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no) 
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes] 
  --enable-silent-rules   less verbose build output (undo: "make V=1") 
  --disable-silent-rules  verbose build output (undo: "make V=0") 
  --enable-dependency-tracking 
                          do not reject slow dependency extractors 
  --disable-dependency-tracking 
                          speeds up one-time build 
  --enable-serial         Specify whether to enable a fake mpi library to run 
                          in serial mode. 
 
Optional Packages: 
  --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes] 
  --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no) 
  --with-psblas=DIR       The install directory for PSBLAS, for example, 
                          --with-psblas=/opt/packages/psblas-3.5 
  --with-psblas-incdir=DIR 
                          Specify the directory for PSBLAS C includes. 
  --with-psblas-moddir=DIR 
                          Specify the directory for PSBLAS Fortran modules. 
  --with-psblas-libdir=DIR 
                          Specify the directory for PSBLAS library. 
  --with-ccopt            additional [CCOPT] flags to be added: will prepend 
                          to [CCOPT] 
  --with-fcopt            additional [FCOPT] flags to be added: will prepend 
                          to [FCOPT] 
  --with-libs             List additional link flags here. For example, 
                          --with-libs=-lspecial_system_lib or 
                          --with-libs=-L/path/to/libs 
  --with-clibs            additional [CLIBS] flags to be added: will prepend 
                          to [CLIBS] 
  --with-flibs            additional [FLIBS] flags to be added: will prepend 
                          to [FLIBS] 
  --with-library-path     additional [LIBRARYPATH] flags to be added: will 
                          prepend to [LIBRARYPATH] 
  --with-include-path     additional [INCLUDEPATH] flags to be added: will 
                          prepend to [INCLUDEPATH] 
  --with-module-path      additional [MODULE_PATH] flags to be added: will 
                          prepend to [MODULE_PATH] 
  --with-extra-libs       List additional link flags here. For example, 
                          --with-extra-libs=-lspecial_system_lib or 
                          --with-extra-libs=-L/path/to/libs 
  --with-blas=<lib>       use BLAS library <lib> 
  --with-blasdir=<dir>    search for BLAS library in <dir> 
  --with-lapack=<lib>     use LAPACK library <lib> 
  --with-mumps=LIBNAME    Specify the libname for MUMPS. Default: autodetect 
                          with minimum "-lmumps_common -lpord" 
  --with-mumpsdir=DIR     Specify the directory for MUMPS library and 
                          includes. Note: you will need to add auxiliary 
                          libraries with --extra-libs; this depends on how 
                          MUMPS was configured and installed, at a minimum you 
                          will need SCALAPACK and BLAS 
  --with-mumpsincdir=DIR  Specify the directory for MUMPS includes. 
  --with-mumpsmoddir=DIR  Specify the directory for MUMPS Fortran modules. 
  --with-mumpslibdir=DIR  Specify the directory for MUMPS library. 
  --with-umfpack=LIBNAME  Specify the library name for UMFPACK and its support 
                          libraries. Default: "-lumfpack -lamd" 
  --with-umfpackdir=DIR   Specify the directory for UMFPACK library and 
                          includes. 
  --with-umfpackincdir=DIR 
                          Specify the directory for UMFPACK includes. 
  --with-umfpacklibdir=DIR 
                          Specify the directory for UMFPACK library. 
  --with-superlu=LIBNAME  Specify the library name for SUPERLU library. 
                          Default: "-lsuperlu" 
  --with-superludir=DIR   Specify the directory for SUPERLU library and 
                          includes. 
  --with-superluincdir=DIR 
                          Specify the directory for SUPERLU includes. 
  --with-superlulibdir=DIR 
                          Specify the directory for SUPERLU library. 
  --with-superludist=LIBNAME 
                          Specify the libname for SUPERLUDIST library. 
                          Requires you also specify SuperLU. Default: 
                          "-lsuperlu_dist" 
  --with-superludistdir=DIR 
                          Specify the directory for SUPERLUDIST library and 
                          includes. 
  --with-superludistincdir=DIR 
                          Specify the directory for SUPERLUDIST includes. 
  --with-superludistlibdir=DIR 
                          Specify the directory for SUPERLUDIST library. 
 
Some influential environment variables: 
  FC          Fortran compiler command 
  FCFLAGS     Fortran compiler flags 
  LDFLAGS     linker flags, e.g. -L<lib dir> if you have libraries in a 
              nonstandard directory <lib dir> 
  LIBS        libraries to pass to the linker, e.g. -l<library> 
  CC          C compiler command 
  CFLAGS      C compiler flags 
  CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir> if 
              you have headers in a nonstandard directory <include dir> 
  MPICC       MPI C compiler command 
  MPIFC       MPI Fortran compiler command 
  CPP         C preprocessor 
 
Use these variables to override the choices made by configure or to help 
it to find libraries and programs with nonstandard names/locations. 
 
Report bugs to <https://github.com/psctoolkit/psctoolkit/issues>.
   

For instance, if a user has built and installed PSBLAS 3.7 under the /opt directory and is using the SuiteSparse package (which includes UMFPACK), then AMG4PSBLAS might be configured with:

./configure --with-psblas=/opt/psblas-3.7/ \
--with-umfpackincdir=/usr/include/suitesparse/

Once the configure script has completed execution, it will have generated the file Make.inc which will then be used by all Makefiles in the directory tree; this file will be copied in the install directory under the name Make.inc.AMG4PSBLAS.

To use the MUMPS solver package, the user has to add the appropriate options to the configure script; by default we are looking for the libraries -ldmumps -lsmumps  -lzmumps -lcmumps -mumps_common -lpord. MUMPS often uses additional packages such as ScaLAPACK, ParMETIS, SCOTCH, as well as enabling OpenMP; in such cases it is necessary to add linker options with the --with-extra-libs configure option.

To build the library the user will now enter

make

followed (optionally) by

make install

3.4 Bug reporting

If you find any bugs in our codes, please report them through our issues page on
https://github.com/psctoolkit/psctoolkit/issues

To enable us to track the bug, please provide a log from the failing application, the test conditions, and ideally a self-contained test program reproducing the issue.

3.5 Example and test programs

The package contains a samples directory, divided in two subdirs simple and advanced; both of them are further divided into fileread and pdegen subdirectories. Their purpose is as follows:

simple

contains a set of simple example programs with a predefined choice of preconditioners, selectable via integer values. These are intended to get acquainted with the multilevel preconditioners available in AMG4PSBLAS.

advanced

contains a set of more sophisticated examples that will allow the user, via the input files in the runs subdirectories, to experiment with the full range of preconditioners implemented in the package.

The fileread directories contain sample programs that read sparse matrices from files, according to the Matrix Market or the Harwell-Boeing storage format; the pdegen programs generate matrices in full parallel mode from the discretization of a sample partial differential equation.