[netcdfgroup] Unlimited dimension and memory usage

• To: netcdfgroup <netcdfgroup@xxxxxxxxxxxxxxxx>
• Subject: [netcdfgroup] Unlimited dimension and memory usage
• From: Ross Williamson <rosswilliamson.columbia@xxxxxxxxx>
• Date: Fri, 30 Dec 2011 17:49:07 +0000

I'm new to using NetCDF so apologies if this is an obvious question.
I should state that I'm using the new C++4 API.

I have a fairly complex set of variables, having either two, three or
four dimensions.  The first dimension is one of two unlimited
dimensions (time_slow,time_fast)  depending on the data rate coming
into the data-logging software.  When a sample is taken,  I add it to
the relevant variable use putVar. Now I've noticed that the memory
usage of my code is gradually increases.  This makes sense if every
sample is now being held in memory.  What I'd like to do is that once
the sample has been written to the file using nc_sync(D_->getID())
(where D_ is a pointer to a NETCDF object) it removes those values
from memory so I can keep on taking data without worrying about
running out of memory.

Ross

-- 
Ross Williamson
Associate Research Scientist
Columbia Astrophysics Laboratory
212-851-9379 (office)
212-854-4653 (Lab)
312-504-3051 (Cell)