[MITgcm-support] mnc questions

[Ed Hill]

On Mon, 2005-12-19 at 15:09 -0600, Michael Schaferkotter wrote:
> martin:
> indeed i 'was' looking to store each variable in a separate netcdf file.
> thanx for appreciating the intent.
> 
> i also appreciate ed/s remarks and strategy of using nco. i believe that works in theory, however
> i haven/t been able to demonstrate that in practice with 'large' domains.
> 
> for the time being, i went along with ed (to a point).
> 
> using
> 
> FC='pgf77'
> CC='gcc'
> 
> LIBS='-L/common/netcdf/x86/3.6.0-p1/pgf-6.02/lib -lnetcdf'
> INCLUDES='-I/common/netcdf/x86/3.6.0-p1/pgf-6.02/include'
> 
> i was able to create a single state.*.nc file but of size
> 
> [me at mach mnc_test_20051217_0001]$ ls -l state.*.nc
> -rw-r--r--  1 me gruppe 4444119560 Dec 18 11:27 state.0000.000001.nc
> 
> even though mnc_max_fsize default is 'supposed' to cap at < 2GB. (not sure why such a big file then)

Hi Michael,

What version of MITgcm are you using?

Based on the MNC output names that I see above, it looks like you're not
using the latest version from CVS.  It looks like you're using something
from at least a few months ago.  Is that the case?  If so, please get
the latest from CVS because old versions simply don't have the
functionality that we've been talking about.


> try to build another way.
> 
> i tried to build with g77 and gcc, but genmake2 disabled mnc because of some failure of the netcdf test programs,
> using g77 and gcc with and without name-mangling yields 
> 
> *********************************************************************
> WARNING: the "mnc" package was enabled but tests failed to compile
>   NetCDF applications.  Please check that:
> 
>   1) NetCDF is correctly installed for this compiler and
>   2) the LIBS variable (within the "optfile") specifies the correct 
>        NetCDF library to link against.
> 
>   Due to this failure, the "mnc" package is now DISABLED.
> 
> the bright side is that with 
> FC_NAMEMANGLE="#define FC_NAMEMANGLE(X) X ## _" we do get to use the 
> stat function
> 
> ===  Checking system libraries  ===
>   Do we have the system() command using g77...  yes
>   Do we have the fdate() command using g77...  yes
>   Do we have the etime() command using g77...  yes
>   Can we call simple C routines (here, "cloc()") using g77...  yes
>   Can we use stat() through C calls...  yes
>   Can we create NetCDF-enabled binaries...  no
> 
> things are certainly not as expected.

Here, the MNC package is disabled because you need to build a version of
netCDF thats compatible with g77.  The g77 and PGI compilers have
different name-mangling so please don't expect the netCDF package you
built for PGI to work with g77.


> i understand why mnc_max_fsize has no effect, but i don/t understand 
> why the files that are being written
> are larger than 2GB. (snapshot_mnc has been toggled and the file 
> size is still > 2GB.)

Again, what version of MITgcm are you using?

Ed

-- 
Edward H. Hill III, PhD
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