You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
94 lines
3.6 KiB
Plaintext
94 lines
3.6 KiB
Plaintext
This directory contains the MLD2P4 set of preconditioners, version 2.1
|
|
|
|
WHAT'S NEW
|
|
|
|
Version 2.1
|
|
1. The multigrid preconditioner now include fully general V- and W-
|
|
cycles. We also support K-cycles, intended to be used in
|
|
conjunction with Flexible CG available in PSBLAS 3.5.
|
|
2. The smoothers now include popular
|
|
variants such as Jacobi, forward and backward hybrid
|
|
Gauss-Seidel (intra-process Gauss-Seidel, inter-process
|
|
block-Jacobi).
|
|
3. The PRE and POST specification for smoothers can now be
|
|
specified independently of each other: you can even specify
|
|
different smoothers for PRE and POST (e.g. forward Gauss-Seidel
|
|
PRE with backward Gauss-Seidel POST). The default is to
|
|
have the specs apply to both PRE and POST.
|
|
|
|
|
|
Version 2.0.
|
|
|
|
Finally moved to F2003, with the support of PSBLAS3.
|
|
There are a few minor differences at user level:
|
|
1. In the configure step, you should specify the INSTALL directory
|
|
of PSBLAS version 3.4, not the source directory;
|
|
2. In the various makefiles, libmld_prec.a should now be used in
|
|
addition (and in front of) libpsb_prec.a, and no longer in
|
|
place of it.
|
|
3. As for the basic usage, this is practically identical to the
|
|
previous version(s).
|
|
|
|
You should use the same MPI/serial compilers that were used for the
|
|
PSBLAS installation.
|
|
The Fortran 2003 support means that it is far easier to develop and
|
|
integrate new solvers and smoothers; you need to take one of the
|
|
existing solvers/smoothers as a model, develop your own by
|
|
changing/replacing the model contents, and then pass the new object
|
|
to the PREC%SET() method which will copy into the internals, as per
|
|
the PROTOTYPE design pattern. Take a look at the test/newslv
|
|
directory to see an example. It's easier done than said!
|
|
|
|
Versions known to work:
|
|
UMFPACK: 5.4
|
|
SuperLU: 4.3 and 5.0
|
|
SuperLU_Dist: 3.3 and 4.2
|
|
Note that with SuperLU_Dist you will probably need to add further
|
|
link options, e.g. the ParMetis library or the openmp runtime;
|
|
you can do this using the configure option --with-extra-libs
|
|
|
|
In version 1.1:
|
|
- The MLD_SIZEOF() function has been redefined to be INTEGER(8), so
|
|
as to be able to measure large data sets.
|
|
- The internals of the multilevel preconditioner have been repackaged
|
|
in a more structured fashion; no changes are needed in the user
|
|
code.
|
|
- Note that we now need version 2.3.1 of PSBLAS.
|
|
|
|
|
|
To compile:
|
|
0. Unpack the tar file in a directory of your choice (preferrably
|
|
outside the main PSBLAS directory).
|
|
1. run configure --with-psblas=<ABSOLUTE path of the PSBLAS install directory>
|
|
adding the options for SuperLU, SuperLU_Dist, UMFPACK as desired.
|
|
2. Tweak Make.inc if you are not satisfied.
|
|
|
|
3. make;
|
|
|
|
4. Go into the test subdirectory and build the examples of your choice.
|
|
|
|
Notes:
|
|
|
|
- The single precision version is supported only by SuperLU; thus, even
|
|
if you specify at configure to use UMFPACK or SuperLU_Dist, the
|
|
corresponding preconditioner options will be available only from the
|
|
double precision version.
|
|
|
|
- A program that was using the PSBLAS precoditioners needs no source
|
|
code changes, but should be recompiled. If the new preconditioner
|
|
(or preconditioner options, such as ILU(N) factorization) are
|
|
required, only the type of the preconditioner object and its
|
|
setup/build/free calls should be updated; the rest of the
|
|
application continues to make use of the PSBLAS existing
|
|
interfaces.
|
|
|
|
|
|
|
|
CREDITS
|
|
|
|
developed by
|
|
Salvatore Filippone
|
|
Pasqua D'Ambra
|
|
Daniela di Serafino
|
|
Alfredo Buttari
|