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[THREDDS #FAQ-337688]: union aggregation and cache

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  • Subject: [THREDDS #FAQ-337688]: union aggregation and cache
  • Date: Tue, 28 Sep 2010 10:58:25 -0600
Hi Massimiliano,

What version of TDS are you running?

The TDS opens a representative dataset when constructing an aggregated dataset. 
So, in this case we would expect the TDS to open all the variable files for a 
single day during the dataset construction. Once that is done it should only 
open the files required to handle a request. Also, if you restart the TDS it 
may use different days as the representative day so that could make it look 
like more files are getting unzipped than expected.

If that doesn't explain what you are seeing, could you send us some sample 
files and we'll look into what is happening? Three days worth of files should 
be enough.

Thanks,

Ethan

Massimiliano Drudi wrote:
> we have a 10 years long dataset, including 5 variables.
> Now we have a number of files, each including 1 variable and covering
> only 1 day.
> 
> The solution we are testing, uses the nested aggregation:
> 
> 
> Let me write:
> 
> <agregation type=JoinExisting variable=time>
> 
> <aggregtion type=union timestep=1>
> <netcdf file var1.gz>
> <netcdf file var2.gz>
> ...
> <netcdf file var5.gz>
> </aggregation>
> 
> ...
> 
> <aggregtion type=union timestep=365*10>
> <netcdf file var1.gz>
> <netcdf file var2.gz>
> ...
> <netcdf file var5.gz>
> </aggregation>
> 
> </aggregation>
> 
> 
> Problem description (i know that one year ago, this problem was
> without solution. And now?)
> 
> If somebody downloads 10 days of var1 data, TDS unzip also the file
> for var2, var3, var4 and var5. Is it possible configure TDS to unzip
> the var1 files only?
> 
> Thanks for your work,
> Massimiliano Drudi


Ticket Details
===================
Ticket ID: FAQ-337688
Department: Support THREDDS
Priority: High
Status: Closed