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[THREDDS #TOA-282078]: random vs penultimate aggregation

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  • Subject: [THREDDS #TOA-282078]: random vs penultimate aggregation
  • Date: Tue, 15 Nov 2011 17:36:09 -0700
Hi Michael,

The advantage is for dynamic collections of data, e.g., archives of real-time 
data that just keep growing. It allows such aggregations to avoid using the 
latest dataset (which might not be complete) as the template for the 
aggregation.

Hope that helps,

Ethan

Michael McDonald wrote:
> Package Version: TDS 4.2
> Operating System: RHEL4
> Hardware: 4x Dual Core AMD Opteron(tm) Processor 880, 32GB RAM
> 
> The default NcML Aggregation method between THREDDS v4.1 and v4.2
> changed from random to penultimate.
> 
> Why was this done?
> 
> Is there a distinct advantage to using penultimate over random for 
> aggregations?
> 
> References:
> http://www.unidata.ucar.edu/projects/THREDDS/tech/tds4.1/reference/ThreddsConfigXMLFile.html
> 
> http://www.unidata.ucar.edu/projects/THREDDS/tech/tds4.2/reference/ThreddsConfigXMLFile.html

Ticket Details
===================
Ticket ID: TOA-282078
Department: Support THREDDS
Priority: High
Status: Closed