[netcdfgroup] HDF backend can't add metadata?

• To: netcdfgroup@xxxxxxxxxxxxxxxx
• Subject: [netcdfgroup] HDF backend can't add metadata?
• From: tom fogal <tfogal@xxxxxxxxxxxx>
• Date: Sat, 22 Jan 2011 15:59:10 -0700

I'm having issues getting NetCDF to work with the HDF5 backend
("NetCDF4" files).  64bit offset files are working fine, even in
parallel [0].

I get the following error at nc_create_par:

  ** ERROR **: could not create mask-data output file: -105, Can't add
  HDF5 file metadata

Occasionally, some of my processes get a bit further, completing a few
def_dim and a def_var call; then I get:

  ** ERROR **: finishing definitions failed: HDF error (-101)

from those processes' nc_enddef call.  Note the leading messages come
from my software, not nc_strerror.

I have tried with both the NC_MPIPOSIX and NC_MPIIO flags.  I've tried
with an info object created from an MPI_Info_create call, as well as
MPI_INFO_NULL.

My nc_create_par call is pretty simple; basically something like:

  nc_create_par(maskfile, NC_NETCDF4 | NC_MPIIO, MPI_COMM_WORLD,
                MPI_INFO_NULL, &nc);

of course, as I mentioned the flags/info change up a bit depending on
what I'm testing.

The NetCDF installation on the cluster I'm using lacks the parallel
functions, so I've built HDF5 and NetCDF in my $HOME.  These seemed to
go through fine.  The configure lines I used for both are at the end of
this email [1,2].  I'm using OpenMPI 1.3.3 for MPI.  The stack is built
with the v11.1 intel compiler.  HDF5 is version 1.8.5-patch1 and NetCDF
is v4.1.1.

What could be going wrong?

-tom

[0] Though I'm seeing incredibly poor scalability, which is part
of what made me want to look at the NetCDF4 backend.  I observe
*increasing* runtime for a strong scalability study.  Is this
consistent with others' experiences?
[1] HDF5 configure line:
  ./configure CC=mpicc --prefix=${HOME}/sw --enable-parallel --disable-fortran
[2] NetCDF configure line:
  ./configure CC=mpicc --prefix=${HOME}/sw --with-hdf5=${HOME}/sw \
    --enable-c-only --enable-netcdf4 --disable-dap --enable-shared --with-pic

• Follow-Ups:
  • Re: [netcdfgroup] HDF backend can't add metadata?
    • From: Ed Hartnett
  • Re: [netcdfgroup] HDF backend can't add metadata?
    • From: Shibaev, Sergei