Parallel netCDF in 64 bits environment

[Jianwei Li]

Yu-heng,

That's great! 
We'll add the $(CFLAGS) in the C compile line of Makefile to
make it consistent.
It worked for me somehow because, on AIX, 32/64-bit mode is
usually enabled by OBJECT_MODE=32/64 which automatically sets
-q32/-q64 as default option (and of course you can override
that default by explicit -q32/-q64).
Anyway, adding both OBJECT_MODE=64 and -q64 should be safe.

Thank you for pointing this out and sharing your experience
with the PnetCDF software.

Jianwei


On Tue, 19 Apr 2005, Yu-Heng Tseng wrote:

> Hi Jianwei,
>
> Thanks so much for your information. It's very helpful. I got it worked in 
> 64bits mode on Seaborg at NERSC.
> There is a minor problem in test case under test/fandc csnap for 64bits 
> option. Probably a bug in Makefile
> The compiler is doing well in Fortran but it compile csnap using 32 bits in C 
> and link using 64 bits. A flag should be added in compiling.
>
> Cheers
>
> Yu-heng
> Jianwei Li wrote:
>
>> 
>> 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
>> 
>> 
>
>