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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 14:56:55 -0600
Patrick,

This turns out to be a known problem with HDF5 performance:

  
http://mail.lists.hdfgroup.org/pipermail/hdf-forum_lists.hdfgroup.org/2012-November/006195.html

--Russ

> In this case, no b-trees are involved, because the data storage is
> contiguous, not chunked (according to ncdump -h -s).  So I'm
> surprised how slow the strided netCDF access is, and suspect there
> might be a performance bug in how netCDF-4 uses the HDF5 API for
> strided access.
> 
> --Russ
> 
> Russ Rew                                         UCAR Unidata Program
> address@hidden                      http://www.unidata.ucar.edu
> 
> 
Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



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