Parallel netCDF in 64 bits environment

[Jianwei Li]

Hi, Yu-heng,

We have already successfully built our pnetCDF on an IBM SP2 in
64-bit mode. As documented in README.SP, the following setting
was used:

    setenv OBJECT_MODE 64
    setenv MPICC  mpcc_r
    setenv MPIF77 mpxlf_r
    setenv F77    xlf
    setenv FC     xlf
    setenv CC     xlc
    setenv CXX    xlC
    setenv CFLAGS -q64
    setenv FFLAGS -q64
    setenv F90FLAGS -q64
    setenv CXXFLAGS -q64

Please let us know if it still doesn't work. And Thanks!

As to netCDF-4.0, as far as I know, it will be built on top of
HDF5, with HDF5 parallel I/O support atop of MPI-IO and new
netCDF API semantics. The physical File Format should be in HDF5.
So, the design, implementation, performance and compatibility
will be quite different between netCDF-4.0 and PnetCDF.
So far, PnetCDF is the only public one that provides high
performance parallel I/O support for traditional netCDF file
format.

Jianwei

On Mon, 18 Apr 2005 YHTseng at lbl.gov wrote:

> Hi
>
> I am trying to utilize the parallel netCDF
> in an existing code to replace its netCDF I/O.
> I realized that the current version (parallel netCDF-pre1)
> couldn't compile sucessfully using 64 bit (-q64) flag.
> Do we have 64 bits parallel netCDF now or we
> have to convert it on our own?
>
> netCDF 4.0 now uses HDF5 to handle its I/O
> and possibly has parallel I/O capacity.
> Any particular difference between netCDF 4.0 and parallel netCDF?
>
> Thanks for the help and clarification!
>
> Yu-heng
>

On Tue, 5 Apr 2005 YHTseng at lbl.gov wrote:

> Hi
>
> I just started to test the parallel netCDF with IBM SP2. However, it
> seems
> the test examples are not working well. Am I doing something wrong?
> I copy an existing xxx.nc file to test.nc
> and run nf_test
>
> However, it keeps telling me mpi file is not found. test.nc is the
> only file
> we need, right?
> Hope anyone can help me out. Thanks.
> Also what's the status of parallel netCDF development? Any progress
> since last
> December?
>
> Cheers
>
> Yu-heng