John et al,
Aggregations are not supposed to leave files open. If they are, thats a bug. The number of open files should typically be less than 1000, no matter how big your aggregations are. It is dependent on the file cache sizes, see:
We set our NetcdfFileCache to match what we set our ulimit max # of open files to (1mil). The hope of this is that as many files as possible are cached in memory by the server, for quicker catalog scans/requests. We never even approach 1mil concurrently open files.
<NetcdfFileCache> <minFiles>1000</minFiles> <maxFiles>1000000</maxFiles> <scour>24 hours</scour> </NetcdfFileCache>
It was also my understanding that ALL of the files in a particular dataset scan need to be touched/opened/checked before being folded into an aggregation (this is upon initial scan for saving into the cache/agg folder). After this initial indexing, the average # of open files will drop off since queries are only picking/choosing a few files from this catalog, but you still need to have all the proper system limits bumped up in order for this initial scan/cache to ever successfully complete in a timely fashion. correct/incorrect?
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