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[netCDF #XIX-708449]: Memory leaks using netcdf4

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  • Subject: [netCDF #XIX-708449]: Memory leaks using netcdf4
  • Date: Thu, 17 Mar 2011 11:28:51 -0600
Hi Ludovic,

> I am working with netcdf4.1.1 and hdf5-1.8.6 (configure with
> --enable-using-memchecker).
> 
> My process creates a netcdf4 file, receives data and adds it to the file.
> It can run during several days.
> 2 problems with that:
> 1) My file has 42 variables, each takes 8Mo in RAM so the memory
> consumption of my process is more than 336Mo.
> 2) Moreover each call to nc_put_var takes memory that is not released.
> 
> To solve the first point each time I do:
> nc_def_var(_fileID, _varName, _varType, 1, _varDim, &l_varID)
> I have added this line:
> nc_set_var_chunk_cache(_fileID, l_varID, 0, 0, 0.75)
> (as described in this post:
> http://www.unidata.ucar.edu/mailing_lists/archives/netcdfgroup/2010/msg00169.html)

That's still the recommended way to avoid wasting too much memory with chunk
caches.

> And I still have the second problem: each call to nc_put_var take memory
> that is not released.
> 
> How can I avoid these memory leaks?

I believe the second problem is fixed in the just announced netCDF-4.1.2 
release 
candidate, which now passes all of our tests using valgrind with no memory 
leaks.

If it's convenient, we'd like to hear whether 4.1.2-rc1 fixes the memory leak
problems you're seeing.

--Russ


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



Ticket Details
===================
Ticket ID: XIX-708449
Department: Support netCDF
Priority: Normal
Status: Closed