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[netCDF #ZFB-587742]: Reading variable with strides very slow

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  • Subject: [netCDF #ZFB-587742]: Reading variable with strides very slow
  • Date: Fri, 09 Aug 2013 11:49:46 -0600
Patrick-

On the netcdf-3 vs netcdf-4 issue I can at the moment
only speculate. As a rule, reading small quantities of data
with netcdf-4 is always slower than netcdf-3 because the
underlying HDF5 file format is based on b-trees rather than the
linear disk layout of netcdf-3. Since vars reads a single
element at a time, that overhead can, I suspect, be significant.
I am, however surprised that it is as large as you show.

=Dennis Heimbigner
 Unidata

=Dennis Heimbigner
  Unidata


Ticket Details
===================
Ticket ID: ZFB-587742
Department: Support netCDF
Priority: Normal
Status: Closed