Dear Md Mahmudul, I think something might be off with your MPI configuration. Could you try to compile a simple Hello world MPI program to see if your MPI is adequately configured? Do you use OpenMPI or MPICH? Best regards BB
On Sunday, January 18, 2026 at 2:44:11 a.m. UTC-5 [email protected] wrote: > Hello deal.ii community, > I hope you all are doing great. I am writing my code in parallel, > following step-55. I am working on time-dependent, incompressible, > parameterized NSE with UQ. I can compile and run my code but if I run my > code in 8 processors it runs in 1 and the give me error for other > processors. > Could anyone please help me to solve the issue? I have attached the code > and parameter file. > > Thanks for your time and help. > > Number of active cells: 16 > > Number of degrees of freedom: 187 (162+25) > > Time step size = 0.02, Number of time steps = 50 > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > Solved in 36 iterations. > > > -------------------------------------------------------- > > An error occurred in line <529> of file > </Users/mdmahmudulislam/dealii-candi/tmp/unpack/deal.II-v9.7.0/include/deal.II/lac/vector.templates.h> > > in function > > typename Vector<Number>::real_type dealii::Vector<float>::l2_norm() > const [number = float] > > The violated condition was: > > dealii::numbers::is_finite(scale * std::sqrt(sum)) > > Additional information: > > In a significant number of places, deal.II checks that some > > intermediate value is a finite number (as opposed to plus or minus > > infinity, or NaN/Not a Number). In the current function, we > > encountered a number that is not finite (its value is (nan,0) and > > therefore violates the current assertion). > > > > This may be due to the fact that some operation in this function > > created such a value, or because one of the arguments you passed to > > the function already had this value from some previous operation. In > > the latter case, this function only triggered the error but may not > > actually be responsible for the computation of the number that is not > > finite. > > > > There are two common cases where this situation happens. First, your > > code (or something in deal.II) divides by zero in a place where this > > should not happen. Or, you are trying to solve a linear system with an > > unsuitable solver (such as an indefinite or non-symmetric linear > > system using a Conjugate Gradient solver); such attempts oftentimes > > yield an operation somewhere that tries to divide by zero or take the > > square root of a negative value. > > > > In any case, when trying to find the source of the error, recall that > > the location where you are getting this error is simply the first > > place in the program where there is a check that a number (e.g., an > > element of a solution vector) is in fact finite, but that the actual > > error that computed the number may have happened far earlier. To find > > this location, you may want to add checks for finiteness in places of > > your program visited before the place where this error is produced. > > One way to check for finiteness is to use the 'AssertIsFinite' macro. > > > Stacktrace: > > ----------- > > #0 2 libdeal_II.g.9.7.0.dylib 0x000000011778f500 > _ZNK6dealii6VectorIfE7l2_normEv + 636: 2 libdeal_II.g.9.7.0.dylib > 0x000000011778f500 _ZNK6dealii6VectorIfE7l2_normEv > > #1 3 step-55 0x0000000104a72300 > _ZN4SNSE29StochasticNavierStokesProblemILi2EE6EnergyEd + 400: 3 step-55 > 0x0000000104a72300 > _ZN4SNSE29StochasticNavierStokesProblemILi2EE6EnergyEd > > #2 4 step-55 0x0000000104a61fe8 > _ZN4SNSE29StochasticNavierStokesProblemILi2EE3runEv + 3048: 4 step-55 > 0x0000000104a61fe8 > _ZN4SNSE29StochasticNavierStokesProblemILi2EE3runEv > > #3 5 step-55 0x0000000104a611cc main + 184: > 5 step-55 0x0000000104a611cc main > > #4 6 dyld 0x000000018bbe9d54 start + > 7184: 6 dyld 0x000000018bbe9d54 start > > -------------------------------------------------------- > > > Calling MPI_Abort now. > > To break execution in a GDB session, execute 'break MPI_Abort' before > running. You can also put the following into your ~/.gdbinit: > > set breakpoint pending on > > break MPI_Abort > > set breakpoint pending auto > > > Best Regards, > Md Mahmudul Islam > Graduate Student, > University of Alabama at Birmingham > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/dealii/ab073ece-e8e0-46e6-bb2a-72949fc1c120n%40googlegroups.com.
