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[netCDF #AMR-714212]: netcdf file size for limited vs unlimited

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  • Subject: [netCDF #AMR-714212]: netcdf file size for limited vs unlimited
  • Date: Wed, 24 Mar 2010 10:05:00 -0600
I believe this has to do with the 
underlying file format used by netcdf.
Because of its semantics, netcdf
must allocate space for all unlimited variables
for each unlimited instance.  Thus, the space
consumed on disk by each unlimited instance
is actually the sum of the space required
for each unlimited variable. Thus, if one
unlimited var is a short
and one is a float, then every
time the unlimited count for the short
variable is extended, it must also allocate
space for the float variable in case, later,
you extend the unlimited count for the float.
If you use netcdf-4 extended (i.e.--enable-netcdf4)
then space allocation is per variable and you 
will not see this kind of effect.


Ticket Details
===================
Ticket ID: AMR-714212
Department: Support netCDF
Priority: Normal
Status: Open