[petsc-users] HDF5Viewer only on worker 0?

[Katharine Hyatt]

Hello,

I’m trying to use PETsc’s HDF5Viewers on a system that doesn’t support parallel HDF5. When I tried naively using

PetscViewer hdf5viewer;
PetscViewerHDF5Open( PETSC_COMM_WORLD, filename, FILE_MODE_WRITE, &hdf5viewer);

I get a segfault because ADIOI can’t lock. So I switched to using the binary format, which routes everything through one CPU. Then my job can output successfully. But I would like to use HDF5 without any intermediate steps, and reading the documentation it was unclear to me if it is possible to ask for behavior similar to the binary viewers from the HDF5 ones - everyone sends their information to worker 0, who then does single-process I/O. Is this possible?

Thanks,
Katharine