3D uses a lot more memory. This is a crazy number (18446744069467867136). How large is your system?
On Mon, Jul 1, 2019 at 7:20 PM Rodrigo Piccinini via petsc-users < [email protected]> wrote: > Hello, > > I'm trying to solve for the first ten smallest eigenvalues of a diffusion > equation in a 3d heterogeneous medium (varying diffusion coefficient), but > I'm getting an error message: > > Traceback (most recent call last): >> File "eigendrake_spe10_v2.py", line 121, in <module> >> es.solve() >> File "SLEPc/EPS.pyx", line 1132, in slepc4py.SLEPc.EPS.solve >> petsc4py.PETSc.Error: error code 55 >> [0] EPSSolve() line 136 in >> /tmp/pip-req-build-6t_4bkg3/src/eps/interface/epssolve.c >> [0] EPSSetUp() line 269 in >> /tmp/pip-req-build-6t_4bkg3/src/eps/interface/epssetup.c >> [0] STSetUp() line 271 in >> /tmp/pip-req-build-6t_4bkg3/src/sys/classes/st/interface/stsolve.c >> [0] STSetUp_Shift() line 119 in >> /tmp/pip-req-build-6t_4bkg3/src/sys/classes/st/impls/shift/shift.c >> [0] KSPSetUp() line 391 in >> /tmp/pip-req-build-070lpqqd/src/ksp/ksp/interface/itfunc.c >> [0] PCSetUp() line 932 in >> /tmp/pip-req-build-070lpqqd/src/ksp/pc/interface/precon.c >> [0] PCSetUp_LU() line 99 in >> /tmp/pip-req-build-070lpqqd/src/ksp/pc/impls/factor/lu/lu.c >> [0] MatLUFactorSymbolic() line 3111 in >> /tmp/pip-req-build-070lpqqd/src/mat/interface/matrix.c >> [0] MatLUFactorSymbolic_SeqAIJ() line 366 in >> /tmp/pip-req-build-070lpqqd/src/mat/impls/aij/seq/aijfact.c >> [0] PetscMallocA() line 390 in >> /tmp/pip-req-build-070lpqqd/src/sys/memory/mal.c >> [0] MatLUFactorSymbolic_SeqAIJ() line 366 in >> /tmp/pip-req-build-070lpqqd/src/mat/impls/aij/seq/aijfact.c >> [0] Out of memory. Allocated: 0, Used by process: 14097043456 >> [0] Memory requested 18446744069467867136 > > > I'm using code from Firedrake Project <https://www.firedrakeproject.org/> > (finite-element method) to discretize the equations. > My code is available here: > https://github.com/rbpiccinini/codes/blob/master/eigendrake/eigendrake_spe10_v2.py > > The code was run with 64GB available as RAM memory. The requested memory > seems to be abnormally high, though. > I'm able to solve for the eigenvalues of a 2d smaller problem. However, if > I try to solve the 3d problem, I get the out of memory error. > > Could anybody help me understand the issue? > > Thanks in advance. > > -- > Rodrigo >
