This should not happen. Send the code to petsc-maint at mcs.anl.gov Barry
On Sep 6, 2010, at 10:54 AM, Leo van Kampenhout wrote: > Hello Barry, Matt, > About this error I am having: > > [2]PETSC ERROR: Nonconforming object sizes! > [2]PETSC ERROR: Mat mat,Vec y: local dim 700536 697068! > > > I am creating my RHS and initial vector from the same DA as the matrix is > from (see below). I even tried with setting RHS==1 instead of loading from > file, to no avail. I found out the error occurs when #PROC=3,5,7,...,8+ but > NOT when #PROC=2,4,8. It might have something to do with differences in > partitioning strategies of Mat and Vec? As you know my gridsize has a rather > unusual value (number of gridpoints is 2101608). > > Leo > > > > call DACreateGlobalVector(da,x,ierr) > call VecDuplicate(x,b,ierr) > (...) > call DAGetMatrix(da,MATMPIAIJ,A,ierr) > (...) > call VecSet(b,one,ierr) > call KSPCreate(MPI_COMM_WORLD,ksp,ierr) > call KSPSetOperators(ksp,A,A,SAME_NONZERO_PATTERN,ierr) > (...) > call KSPSolve(ksp,b,x,ierr) > > > > > 2010/9/3 Barry Smith <bsmith at mcs.anl.gov> > > You initial vectors must be created with the same DA that is associated > with the Matrix for the layout to be automatically correct. Use > DACreateGlobalVector() instead of VecCreate(). You may already be doing this > and then the problem is more subtle. Let us know. > > Barry > > Something may be going wrong with the copy header > > On Sep 3, 2010, at 11:35 AM, Matthew Knepley wrote: > >> On Fri, Sep 3, 2010 at 5:50 PM, Leo van Kampenhout <lvankampenhout at >> gmail.com> wrote: >> Thanks. Following this conversation closely, i have already built petsc with >> --with-debugging=0 and found that then thing work better there. Until there >> is a ultimate fix I'm perfectly happy with that. >> >> Even on my cluster, I can now run the program for 2,4,8 cores. But there is >> always a catch... with 10 cores, GMRES breaks down! (see below) Sorry to >> bother you with this, it seems unrelated at first sight. Should I issue a >> new thread for this? >> >> This is almost certainly somewhere you are not careful about constructing >> a Vec with the proper layout (as the message says). In fact, from the trace >> it looks like the rhs Vec passed in is not compatible with the matrix. >> >> Matt >> >> Regards, Leo >> >> [5]PETSC ERROR: --------------------- Error Message >> ------------------------------------ >> [5]PETSC ERROR: Nonconforming object sizes! >> [5]PETSC ERROR: Mat mat,Vec y: local dim 210161 213282! >> [5]PETSC ERROR: >> ------------------------------------------------------------------------ >> [5]PETSC ERROR: Petsc Development HG revision: >> 6da7d8c5aaa81099861622f4e6bf1087652253a7 HG Date: Fri Sep 03 15:06:40 2010 >> +0200 >> [5]PETSC ERROR: See docs/changes/index.html for recent updates. >> [5]PETSC ERROR: See docs/faq.html for hints about trouble shooting. >> [5]PETSC ERROR: See docs/index.html for manual pages. >> [5]PETSC ERROR: >> ------------------------------------------------------------------------ >> [5]PETSC ERROR: ./main on a linux-opt named node164 by s1459295 Fri Sep >> 3 17:44:26 2010 >> [5]PETSC ERROR: Libraries linked from >> /home/s1459295/install/petsc-dev/linux-optimized/lib >> [5]PETSC ERROR: Configure run at Fri Sep 3 15:28:20 2010 >> [5]PETSC ERROR: Configure options --with-debugging=0 >> [5]PETSC ERROR: >> ------------------------------------------------------------------------ >> [5]PETSC ERROR: MatMult() line 1976 in src/mat/interface/matrix.c >> [5]PETSC ERROR: KSPInitialResidual() line 55 in src/ksp/ksp/interface/itres.c >> [5]PETSC ERROR: KSPSolve_GMRES() line 236 in src/ksp/ksp/impls/gmres/gmres.c >> [5]PETSC ERROR: KSPSolve() line 427 in src/ksp/ksp/interface/itfunc.c >> >> >> >> >> >> 2010/9/3 Jed Brown <jed at 59a2.org> >> >> On Fri, 3 Sep 2010 09:15:09 -0600 (GMT-06:00), Shri <abhyshr at mcs.anl.gov> >> wrote: >> > Leo, >> > Jed and I both tried running a MatLoad example (see >> > src/dm/da/examples/tests/ex35.c) with petsc configured in debug mode and >> > had issues running it with your grid size 202 X 102 X 102. This example >> > runs in a reasonable amount of time with the optimized petsc build. >> > I suggest running your code on a smaller grid (100 X100 X 100 seems to >> > work fine in the debug mode) for now, get it working and then using the >> > optimized petsc build (--debugging=0) for the large grid size. >> >> I wrote an improved sort that doesn't have this bad behavior, but I'm >> trying to figure out why the old one is okay in optimized mode. See >> here: >> >> http://gist.github.com/563948 >> >> The MEDIAN macro chooses the median of the first, last, and middle >> element in the segment. Performance looks like >> >> FAST -O1: 2.0 seconds >> FAST -O0: 5 seconds >> SLOW -O1: 2.3 seconds >> SLOW -O0: more than an hour >> >> SLOW, which is basically the old implementation does a lot of shuffling >> with the array and ends up hitting a bad case for quicksort (even with >> the median choice). What I don't understand, is that apparently >> building SLOW with -O1 transforms the algorithm into something >> asymptotically faster. The assembly is a few hundred lines, and it's >> not obvious to me what this transform would be. >> >> Jed >> >> >> >> >> -- >> What most experimenters take for granted before they begin their experiments >> is infinitely more interesting than any results to which their experiments >> lead. >> -- Norbert Wiener > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20100906/09745c68/attachment.html>
