[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: large netCDF data sets on AIX platforms

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: Re: large netCDF data sets on AIX platforms
  • Date: Wed, 01 Sep 2004 09:01:13 -0600
Hi Tom,

> I've been back working on this since I received your last message.  Your 
> success at writing the larger file from the Fortran program on bluesky 
> strongly indicated that I'd either installed things incorrectly or 
> there's something different about our system here.  I reinstalled netCDF 
> using your precise environment variable specifications.  The wrf_test.f 
> job aborted at the same 2.147Gb size.  That almost had to mean it was 
> some sort of system problem.  I sat down with one of our IBM 
> consultants.  He could not determine why there should be such a limit in 
> writing out that file since we routinely write out much larger (binary) 
> files.  We have a small IBM test system here that has somewhat different 
> specifications than the large operational ones.  He moved everything 
> over to that test system and successfully produced the netCDF output 
> file with 2.66Gb that you produced.  He is sending this information to 
> IBM to find out why the problem exists on our production machines.

In case it helps isolate the error, I've simplified the configuration
a little bit, to get something minimal that works for us on the large
file tests:

  CC=/usr/vac/bin/xlc
  CFLAGS='-g -q64 -D_LARGE_FILES'
  FC=/bin/xlf
  FFLAGS='-g -q64'
  F90=/bin/xlf90
  F90FLAGS='-g -q64 -qsuffix=f=f90'
  CXX=/usr/vacpp/bin/xlC
  CXXFLAGS='-g -q64 -D_LARGE_FILES'
  ARFLAGS='-X64 cru'
  NMFLAGS=-X64

--Russ