Ok:
If I run KSP ex 2 with parameters "-ksp_type pipecg -ksp_norm_type
natural", it works.
If I try *any* other norm, it fails, but with a different error message,
for example if I try "preconditioned":
[0]PETSC ERROR: --------------------- Error Message
--------------------------------------------------------------
[0]PETSC ERROR: Invalid argument
[0]PETSC ERROR: Scalar value must be same on all processes, argument # 2
[0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html
for trouble shooting.
[0]PETSC ERROR: Petsc Release Version 3.5.2, unknown
[0]PETSC ERROR: ./ex2 on a arch-linux2-c-debug named hakostra-kontor by
hakostra Thu Nov 20 16:04:37 2014
[0]PETSC ERROR: Configure options --prefix=/opt/petsc/git-debug/install
--with-shared-libraries --download-hypre --with-64-bit-indices
--with-hdf5 --with-hdf5-dir=/opt/HDF5/1.8.13/install --with-debugging
--with-debugger=gdb
[0]PETSC ERROR: #1 VecAXPY() line 634 in
/opt/petsc/git-debug/source/src/vec/vec/interface/rvector.c
[0]PETSC ERROR: #2 KSPSolve_PIPECG() line 153 in
/opt/petsc/git-debug/source/src/ksp/ksp/impls/cg/pipecg/pipecg.c
[0]PETSC ERROR: #3 KSPSolve() line 459 in
/opt/petsc/git-debug/source/src/ksp/ksp/interface/itfunc.c
[0]PETSC ERROR: #4 main() line 75 in /home/hakostra/Dropbox/KSP-ex2/ex2.c
Håkon
On 20. nov. 2014 15:49, Sascha Schnepp wrote:
Hi,
this is an error that occurs when calling ksp->converged and having
ksp->normtype == KSP_NORM_NONE
In pipecg.c the error occurs here:
line99: ierr =
(*ksp->converged)(ksp,0,dp,&ksp->reason,ksp->cnvP);CHKERRQ(ierr); /* test for
convergence */
It can be fixed (though there might be a nicer way) using this replacement
code, wich explicitly calls KSPConvergendSkip for the respective norm:
if (ksp->normtype == KSP_NORM_NONE) {
ierr = KSPConvergedSkip (ksp,0,dp,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
} else {
ierr = (*ksp->converged)(ksp,0,dp,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
}
The issue could be related to this code in
KSPCreate_PIPECG
ierr =
KSPSetSupportedNorm(ksp,KSP_NORM_UNPRECONDITIONED,PC_LEFT,2);CHKERRQ(ierr);
ierr =
KSPSetSupportedNorm(ksp,KSP_NORM_PRECONDITIONED,PC_LEFT,2);CHKERRQ(ierr);
ierr = KSPSetSupportedNorm(ksp,KSP_NORM_NATURAL,PC_LEFT,2);CHKERRQ(ierr);
ierr = KSPSetSupportedNorm(ksp,KSP_NORM_NONE,PC_LEFT,2);CHKERRQ(ierr);
where all norms have the same priority.
For the non-pipelined version of CG the unpreconditioned norm has a priority
level of 3.
The modifications are independent. Choosing different default priorities will
still make line 99 fail if type NONE is chosen explicitly.
Cheers,
Sascha
Begin forwarded message:
On Thu, Nov 20, 2014 at 4:05 AM, H?kon Strandenes <[email protected]>
wrote:
Hi,
First: thanks to the list and Barry for solving my previous problem on
loading vectors from HDF5 files. It works great!
Now a second problem: I want to try the pipelined KSP solvers, PIPECG in
particular. However, my program fails on the first KSPSolve() with the
message below. The same happens if I try PIPECR.
These are very new, so there could be bugs lurking. It would help our
testing if this is
reproducuble on a standard example. Does this happen if you try to solve
KSP ex2
or SNES ex5 with PIPECG?
Thanks,
Matt
I have tried this on three MPI implementations, on and two of them fully
support MPI 3 (I have read http://www.mcs.anl.gov/petsc/
documentation/faq.html#pipelined). I am using latest PETSc from Git repo.
I have tried to turn off the preconditioner without any effect.
The equation system is the result of a finite-volume discretization of a
Poisson-like equation if that helps anything. A normal CG solver works like
a charm, converging fast and effective.
Are there any tricks to get this working? Anything special I have to set
and/or define to get this solver running?
Thanks in advance.
Best regards,
H?kon Strandenes
Error message:
[0]PETSC ERROR: --------------------- Error Message
--------------------------------------------------------------
[0]PETSC ERROR: Object is in wrong state
[0]PETSC ERROR: Use KSPConvergedSkip() with KSPNormType of KSP_NORM_NONE
[0]PETSC ERROR: See http://www.mcs.anl.gov/petsc/documentation/faq.html
for trouble shooting.
[0]PETSC ERROR: Petsc Release Version 3.5.2, unknown
[0]PETSC ERROR: madns on a arch-linux2-c-debug named hakostra-kontor by
hakostra Thu Nov 20 11:04:28 2014
[0]PETSC ERROR: Configure options --prefix=/opt/petsc/git-debug/install
--with-shared-libraries --download-hypre --with-64-bit-indices --with-hdf5
--with-hdf5-dir=/opt/HDF5/1.8.13/install --with-debugging
--with-debugger=gdb
[0]PETSC ERROR: #1 KSPConvergedDefault() line 710 in
/opt/petsc/git-debug/source/src/ksp/ksp/interface/iterativ.c
[0]PETSC ERROR: #2 KSPSolve_PIPECG() line 99 in
/opt/petsc/git-debug/source/src/ksp/ksp/impls/cg/pipecg/pipecg.c
[0]PETSC ERROR: #3 KSPSolve() line 459 in /opt/petsc/git-debug/source/
src/ksp/ksp/interface/itfunc.c
[0]PETSC ERROR: #4 findPressure() line 53 in /opt/MaDNS/source/src/FVM2.cpp
