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[netCDF #ESK-579185]: Re: access to /glade file that demos large block size performance problem

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  • Subject: [netCDF #ESK-579185]: Re: access to /glade file that demos large block size performance problem
  • Date: Wed, 04 Jan 2012 15:55:31 -0700
Gary,

> Unrelated, but a quick question - why are the ncid values I get from
> nf_open so large and in units of 65,536?

Good question, it's an artifact of how netCDF-4 combines both the file
ID and the group ID into one 32-bit integer for netCDF-4.  So with
2^16 open files each of which has 2^16 groups, you would use up all the
2^32 integers with group IDs of open netCDF files.

--Russ

Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: ESK-579185
Department: Support netCDF
Priority: Normal
Status: Closed